EE0314- POWER ELECTRONICS LAB REFERENCE MANUAL

Size: px
Start display at page:

Download "EE0314- POWER ELECTRONICS LAB REFERENCE MANUAL"

Transcription

1 EE0314- POWER ELECTRONICS LAB REFERENCE MANUAL SEMESTER VI DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING SRM UNIVERSITY KATTANKULATHUR

2 EXPT. NO. 1 : Pre lab Questions Single Phase Half Converter 1. What is the delay angle control of converters? 2. What is natural or line commutation? 3. What is the principle of phase control? 4. What is extinction angle? 5. Can a freewheeling diode be used in this circuit and justify the reason? 2

3 SINGLE PHASE HALF CONTROLLED BRIDGE RECTIFIER Aim: To study the operation of single phase half controlled converter using R and RL load and to observe the output waveforms. Apparatus required: 1. Power thyristors 2. Rheostat 3. CRO 4. Transformer (1-phase) 230V/24V 5. Connection wires Single Phase Half Controlled Bridge Rectifier: Circuit Diagram 3

4 Model Graph: Observation Table: Serial No Triggering angle α degree Output voltage Vo (volt) (measured) Time period(ms) Procedure: 1. Make the connections as per the circuit diagram. 2. Connect CRO and voltmeter across the load. 3. Keep the potentiometer at the minimum position. 4. Switch on the step down ac source. 5. Check the gate pulses at G1-K1 & G2-K2, respectively. 6. Observe the wave form on CRO and note the triggering angle α and 7. Note the corresponding reading of the voltmeter. Also note the value of Maximum amplitude Vm from the waveform. 4

5 8. Set the potentiometer at different positions and follow the step given in (6) for every position. 9. Tabulate the readings in the observation column. Theory: A semi converter uses two diodes and two thyristors and there is a limited control over the level of dc output voltage. A semi converter is one quadrant converter. A one-quadrant converter has same polarity of dc output voltage and current at its output terminals and it is always positive. It is also known as twopulse converter. Figure shows half controlled rectifier with R load. This circuit consists of two SCRs T1 and T2, two diodes D1 and D2. During the positive half cycle of the ac supply, SCR T1 and diode D2 are forward biased when the SCR T1 is triggered at a firing angle ωt = α, the SCR T1 and diode D2 comes to the on state. Now the load current flows through the path L - T1- R load D2 - N. During this period, we output voltage and current are positive. At ωt = π, the load voltage and load current reaches to zero, then SCR T1 and diode D2 comes to off state since supply voltage has been reversed. During the negative half cycle of the ac supply, SCR T2 and diode D1 are forward biased. When SCR T2 is triggered at a firing angle ωt = π + α, the SCR T2 and diode D1 comes to on state. Now the load current flows through the path N - T2- R load D1 -L. During this period, output voltage and output current will be positive. At ωt = 2π, the load voltage and load current reaches to zero then SCR T2 and diode D1 comes to off state since the voltage has been reversed. During the period (π + α to 2π) SCR T2 and diode D1 are conducting. Vout=( 2Vs)(1+Cosα)/π Result: Thus the operation of single phase half controlled converter using R and RL load has studied and the output waveforms has been observed. 5

6 Post lab Questions: Single Phase Half Converter 1. What is conduction angle? 2. What are the effects of adding freewheeling diode in this circuit? 3. What are the effects of removing the freewheeling diode in single phase semi converter? 4. Why is the power factor of semi converters better than that of full converters? 5. What is the inversion mode of converters? 6

7 EXPT. NO. 2: Pre lab Questions: Single Phase Full Converter: 1. State the type of commutation used in this circuit? 2. What will happen if the firing angle is greater than 90 degrees? 3. What are the performance parameters of rectifier?. 4. What are the advantages of three phase rectifier over a single phase rectifier? 5. What is the difference between half wave and full wave rectifier? 7

8 SINGLE PHASE FULLY CONTROLLED CONVERTER Aim: To study the operation of single phase fully controlled converter using R and RL load and to observe the output waveforms. Apparatus Required: 1. Power thyristors 2. Rheostat 3. CRO 4. Transformer (1-phase) 230V/24V 5. Connection wires Circuit Diagram 8

9 Model Graph: Observation Table: Serial No Triggering angle α degree Output voltage Voav (volt) (measured) Time period(ms) Procedure: 1. Single Phase Fully Controlled Bridge Rectifier 2. Make the connections as per the circuit diagram. 3. Connect CRO and multimeter (in dc) across the load. 9

10 4. Keep the potentiometer (Ramp control) at the minimum position (maximum resistance). 5. Switch on the step down ac source. 6. Check the gate pulses at G1-K1, G2-K2,G3-K3,& G4-K4 respectively. 7. Observe the waveform on CRO and note the triggering angle α and note the corresponding reading of the multimeter. Also note the value of maximum amplitude Vm from the waveform. 8. Set the potentiometer at different positions and follow the step given in (6) for every position. 9. Tabulate the readings in observation column. 10. Draw the waveforms observed on CRO. Theory: A fully controlled converter or full converter uses thyristors only and there is a wider control over the level of dc output voltage. With pure resistive load, it is single quadrant converter. Here, both the output voltage and output current are positive. With RL- load it becomes a two-quadrant converter. Here, output voltage is either positive or negative but output current is always positive. Figure shows the quadrant operation of fully controlled bridge rectifier with R-load. Fig shows single phase fully controlled rectifier with resistive load. This type of full wave rectifier circuit consists of four SCRs. During the positive half cycle, SCRs T1 and T2 are forward biased. At ωt = α, SCRs T1 and T3 are triggered, then the current flows through the L T1- R load T3 N. At ωt = π, supply voltage falls to zero and the current also goes to zero. Hence SCRs T1 and T3 turned off. During negative half cycle (π to 2π). SCRs T3 and T4 forward biased. At ωt = π + α, SCRs T2 and T4 are triggered, then current flows through the path N T2 R load- T4 L. At ωt = 2π, supply voltage and current goes to zero, SCRs T2 and T4 are turned off. The Fig-3, shows the current and voltage waveforms for this circuit. For large power dc loads, 3-phase ac to dc converters are commonly used. The various types of three-phase phase-controlled converters are 3 phase half-wave converter, 3-phase semi converter, 3-phase full controlled and 3-phase dual converter. Three-phase half-wave converter is rarely used in industry because it introduces dc component in the supply current. Semi converters and full converters are quite common in industrial applications. A dual is used only when reversible dc drives with power ratings of several MW are required. The advantages of three phase converters over single-phase converters are as under: In 3-phase 10

11 converters, the ripple frequency of the converter output voltage is higher than in single-phase converter. Consequently, the filtering requirements for smoothing out the load current are less. The load current is mostly continuous in 3-phase converters. The load performance, when 3- phase converters are used, is therefore superior as compared to when single-phase converters are used. Vout=(2Vs)(Cosα)/π Iavg=Vavg/R Result: Thus the operation of single phase fully controlled converter using R and RL load has been studied and the output waveforms has been observed. 11

12 Post lab questions Single phase full converter 1. If firing angle is greater than 90 degrees, the inverter circuit formed is called as? 2. What is displacement factor? 3. What is Dc output voltage of single phase full wave controller? 4. What are the effects of source inductance on the output voltage of a rectifier? 5. What is commutation angle of a rectifier? 6. What are the advantages of three phase rectifier over a single phase rectifier? 12

13 EXPT. NO: 3 Pre lab questions Single phase AC voltage controller using TRIAC 1. Why should the two trigger sources be isolated? 2. What are the advantages and the disadvantages of phase control? 3. What is phase control? 4. What are the advantages of bidirectional controllers? 5. What is meant by duty cycle in ON-OFF control method? 13

14 1-PHASE AC VOLTAGE CONTROL USING TRIAC Aim: To study the 1-phase AC voltage control using TRIAC. Apparatus Required: i) Lamp 60W ii) Resistor / 1W iii) Potentio meter 100K iv) Capacitor 0.1 F / 400V v) Resistor 1K vi) DIAC DB3 vii) TRIAC BT 136 viii) Unearthed oscilloscope Circuit Diagram Circuit Operation: 1. When potentiometer is in minimum position drop across potentiometer is zero and hence maximum voltage is available across capacitor. This V c shorts the diac (V c > V bo ) and triggers the triac turning triac to ON state there lamp glows with maximum intensity. 14

15 2. When the potentiometer is in maximum position voltage drop across potentiometer is maximum. Hence minimum voltage is available across capacitor (V c M V bo ) hence triac to is not triggered hence lamp doesnot glow. 3. When potentiometer is in medium position a small voltage is available across capacitor hence lamp glows with minimum intensity. Tabular Column: S.No. Firing Angle(α) Output Voltage(Volts) Time period(ms) Procedure: 1. Connections are given as per the circuit diagram 2. Initially potentiometer kept at minimum position so lap does not glow at this instant. 3. Note the voltage across the diac and triac. 4. Capacitor and potentiometer using multimeter and CRO. 5. Potentiometer is now placed at medium and then to minimum position and their voltages were noted. Theory: Triac is a bidirectional thyristor with three terminals. Triac is the word derived by combining the capital letters from the words TRIode and AC. In operation triac is equivalent to two SCRs connected in antiparallel. It is used extensively for the control of power in ac circuit as it can conduct in both the direction. Its three terminals are MT1 (main terminal 1), MT2 (main terminal 2) and G (gate). 15

16 Result: Thus the operation and performance of the 1-phase AC voltage control using DIAC and TRIAC. 16

17 Post lab questions Single Phase AC voltage controller using TRIAC 1. What type of commutation is used in this circuit? 2. What are the effects of load inductance on the performance of AC voltage controllers? 3. What is extinction angle? 4. What are the disadvantages of unidirectional controllers? 5. What are the advantages of ON-OFF control? 17

18 EXPT. NO. 4: Prelab questions Modified Mc Murray Full bridge Inverter 1. What is the difference between Mcmurray half bridge and full bridge inverter? 2. What is meant by Mcmurray inverter? 3. What is the type of commutation used in this circuit? 4. What is the other name for this inverter circuit? 5. Advantages of Mc Murray inveter? 18

19 MODIFIED MC-MURRAY BEDFORD FULL BRIDGE INVERTER Aim: To study the operation of a modified Mc-Murray Bedford full bridge inverter. Apparatus Required: i) Modified Mc-Murray Bedford inverter kit ii) Connecting wires iii) CRO and probes Circuit Diagram 19

20 Model Graph Tabular Column: S.No Frequency Voltage Amplitude(V) Time period(ms) 1 Minimum 2 Maximum Procedure: i) Connections are made as per the circuit diagram ii) Power supply is switched ON and the output waveforms are noted. Theory: The power circuit diagrams of a modified Mc-Murray Bedford half and full bridge inverter is shown in the figure. 20

21 A half bridge modified Mc-Murray Bedford inverter uses lesser number of thyristors and diodes as compared with the full bridge one. The inverter consists of main thyristors T1,T2 and feedback diodes D1, D2 commutation circuitry consists of two capacitors C1, C2 and magnetically coupled inductors L1 and L2 constitute one inductor with a center rapped so that L1 = L2 = L. The inductance of the order 50 H. The inductor is wound on a core with an air gap so as to avoid saturation. The value of the capacitance for the two capacitors is the same (C1=C2=C). It is a voltage commutated VSI. In a branch consisting of two tightly coupled inductors in series with two thyristors if the thyristors is turned on, then the other thyristor is turned off automatically. This type of commutation is called complementary commutation. 21

22 Result: Thus the operation of a modified Mc-Murray Bedford full bridge inverter is studied and the waveforms are drawn. 22

23 EXPT. NO. 5: Pre lab Questions Single Phase parallel Inverter 1. What is parallel inverter? Why is it called so? 2. What is the purpose of capacitor in the parallel inverter? 3. What is the purpose of transformer in the parallel inverter? 4. IS the parallel inverter naturally commutated or force commutated? 5. What are the advantages of parallel resonant inverters? 23

24 PARALLEL INVERTER Aim: To study the operation of parallel inverter. Apparatus Required: i) Parallel inverter kit ii) Inductor iii) Transformer iv) CRO This module consists of two units (1) Firing circuit and 92) Power circuit. Circuit Diagram 24

25 Model Graph Tabular Column: S.No. Frequency Voltage Amplitude(V) Time period(ms) 1 Minimum 2 Maximum Procedure: 1. Switch on the firing circuit. Observe the trigger outputs T P and T N by varying frequency potentiometer and by operating ON/OFF switch. 2. Then connect input DC supply to the power circuit. Connect trigger outputs to Gate and Cathode of SCR T P & T N. 3. Apply trigger pulses to SCR 4. Observe voltage waveforms across load. Output voltage is square wave only. 5. Vary the load, vary the frequency and observe waveforms. 25

26 Theory: The circuit is a typical class C Parallel inverter. Assume T N to be ON and T P to be OFF. The bottom of the commutating capacitor is charged to twice the supply voltage and remains at this value until T P is turned on. When T P is turned on, the current flows through lower half of the primary T P and commutating inductance L. Since voltage across C cannot instantaneously, the common SCR cathode point rises approximately to 2V dc and reverses bias T N Thus T N turns off and C discharges through L, the supply circuit and then recharges in the reverse direction. The autotransformer action makes C to charge making now its upper point to reach +2V dc volts ready to commutate Tp, When T N is again turned on and the cycle repeats. Free wheeling diodes Dp and D N assist the inverter in handling a wide range of loads and the value of C may be reduced since the capacitor now does not have to carry the reactive current. To dampen the feedback diode currents within the half period, feedback diodes are connected to tapping of the transformer at 25V tapping. (1) Firing Circuit: This unit generates two pairs of pulse transformer isolated trigger pulses to trigger two SCR s connected in center tapped transformer type parallel inverter. Frequency of the inverter can be varied from 75Hz to 200 Hz approximately. (2) Power Circuit: This unit consists of two SCR s, two free wheeling diodes, commutation inductor, commutation capacitor and a center tapped transformer to be inter connected to make parallel inverter. All the points are brought out to the front panel. A switch and fuse is provided for input DC supply. All the devices are mounted on proper heat sink. Each device is protected by snubber circuit. Front Panel Details: 1. Frequency : Potentiometer to vary the inverter frequency from 75Hz to 200 Hz approximately. 2. ON / OFF : Switch for trigger outputs 3. T1 & T2 : Trigger outputs 4. Power : Mains switch for firing circuit 5. Vdc in : Terminals for DC input from 30V/2A RPS unit 26

27 6. ON : Switch for DC input 7. Tp & Tn : SCR s 10A/600V 8. Dp & Dn : Diodes 10A/600V 9. L : Inductance H/2A 10. C : 6.8 F/100V 11. Load : Terminals to connect load. 12. O : Transformer center tap point which should be connected to positive of DC supply after fuse. 13. Fuse : 2A Glass fuse. 14. Output Transformer : Primary 30V-25V-025V 30V Secondary 0-30V/2Amps. 27

28 Result: drawn. Thus the operation of a parallel inverter is studied and the output waveforms are measured and 28

29 Post lab questions Single phase parallel Inverter 1. What is the purpose of the inductor in the parallel inverter? 2. During its operation, capacitor voltage reaches 2Vs. How? 3. What is the significance of the split phase transformer? 4. During operation, what is the voltage across primary winding of the transformer? 5. Capacitor current flows in how many modes of the operation of parallel inverter? 29

30 EXPT.NO 6: Pre Lab questions R, R-C AND UJT TRIGGERING CIRCUITS 1. UJT triggering circuit is also known as? 2. Types of triggering circuit? 3. What is the purpose of series resistor? 4. What is the condition for triggering the circuit? 5. What is the function of pulse transformer in firing circuit? 30

31 Aim: R, R-C AND UJT TRIGGERING CIRCUITS To study the operation of resistance, resistance capacitance and UJT triggering circuits of SCR Circuit Diagram: R Triggering Circuit: 31

32 Model Graph: R Triggering Circuit: Tabular Column 1 S.No. Input Voltage (V) Input Cycle Time (Ms) Voltage across Resistor(V) Voltage across zener diode (V) Voltage across capacitor (V) Voltage across load (V) Procedure R Firing 1. Connections are made as shown in fig. 2. Switch on the power supply to the CRO. 3. Set the CRO to the line trigger mode. 4. Switch on power supply to the SCR trainer. 32

33 5. Observe the waveform on the CRO. 6. Study the waveforms for various firing angle by varying the pot in R trigger circuit. 7. Observe the range of firing angle control. 8. For any one particular firing angle plot the waveforms of the ac voltage, voltage across the load and the SCR. 9. Measure the average dc voltage across the load and rms value of the ac input voltage using a digital multimeter. 10. Calculate the dc output voltage using the equation. V - Vrms value of ac input voltage Vm - \/2Vrms.And compare the measured value. Theory: Resistance Triggering: Resistance trigger circuits are the simplest & most economical method. During the positive half cycle of the input voltage, SCR become forward biased but it will not conduct until its gate current exceeds Igmin. Diode D allows the flow of current during positive half cycle only. R2 is the variable resistance & R is the stabilizing resistance.r1 is used to limit the gate current. During the positive half cycle current Ig flows. Ig increases and when Ig= Igmin the SCR turns ON.The firing angle can be varied from 0 90 by varying the resistance R. 33

34 Circuit Diagram: RC Triggering Circuit: Model Graph: 34

35 Tabular Column: S.No. Input Voltage (V) Input Cycle Time (Ms) Resistance Value (K _ ) O/P Voltage V rms (V) Voltage Across (Anode- Cathode) V rms (V) Procedure: RC FIRING: 1. Connections are made as shown in fig. 2. Switch on the power supply to the CRO. 3. Set the CRO to the line trigger mode. 4. Switch on power supply to the SCR trainer. 5. Observe the waveform on the CRO. 6. Study the waveforms for various firing angle by varying the pot in R trigger circuit. 7. Observe the range of firing angle control. t u t e o f T e c h n o l o g y Page For any one particular firing angle plot the waveforms of the ac voltage, voltage across the load and the SCR. 9. Measure the average dc voltage across the load and rms value of the ac input voltage using g' a digital millimeter. 10. Calculate the dc output voltage using the equation. 35

36 Theory: R C Triggering: By varying the variable resistance R, the firing angle can be varied from In the negative half cycle the capacitance C charges through the diode D2 with lower plate positive to, the peak supply voltage Emax.This Capacitor voltage remains constant at until supply voltage attains zero value. During the positive half cycle of the input voltage, C begins to charge through R. When the capacitor voltage reaches the minimum gate trigger voltage SCR will turn on. Circuit Diagram: UJT Triggering Circuit 36

37 Model Graph: Tabular Column: Resistor value(r) (ω) Capacitor voltage Vc Charging time (ms) Discharging Time (ms) Voltage vo (v) Time Period (ms) Procedure: 1. Connect a & k terminal of UJT triggering circuit to the gate cathode terminals of SCR. 2. Give a 24 V ac supply. 3. Observe the waveforms and plot it for one particular firing angle by adjusting the potentiometer 37

38 and observe the range over which firing angle is controllable. 4. Observe that capacitor voltage is set at every half cycle. Theory: A synchronized UJT triggered circuit using an UJT is shown in the figure. Diodes D1 to D4 rectify ac to dc. Resistor R1 lowers Vdc to a suitable value for the zener diode and UJT. Zener diode Z functions to clip the rectified voltage to a standard level, Vz which remains constant except near the Vdc zero. The voltage Vz is applied to the charging circuit RC. Current I, charges capacitor c at a rate determined by R voltage across capacitor is marked by Vc as shown. When Vc reaches the unijunction threshold voltage Vz, the t-b1 junction of UJT breaks down and the capacitor c discharges through the primary of pulse transformer sending a current C2 as shown. As the current i2 is in the form of pulse, windings of the pulse transformer have pulse voltages at their secondary terminals. Pulse at the two secondary windings feeds the same in phase pulse to two SCRs of a full wave circuits. SCR with positive anode voltage would turn ON. As soon as the capacitor discharges, it starts to recharge as shown. Rate of rise of capacitor voltage can be controlled by varying R. The firing angle can be controlled up to above 150o. This method of controlling the output power by varying the charging resistor r is called ramp control, open loop control (or) manual control. 38

39 Result: been studied. Thus the operation of resistance, resistance capacitance and UJT triggering circuits of SCR has 39

40 Post lab questions R, R-C AND UJT TRIGGERING CIRCUITS 1. Explain how synchronization of the triggering circuit with the supply voltage across SCR is achieved? 2. How can the capacitor charging be controlled? 3. What is the maximum value of firing angle which can be obtained from the circuit? 4. How is the output power to the triggering circuit controlled? 5. Compare UJT triggering circuit with RC firing circuit? 40

41 EXPT. NO. 7: Pre lab questions SERIES INVERTER 1. Why is this circuit called as series inverter? 2. What is the type of commutation for series inverter? 3. What is the configuration of inductor? 4. What is the principle of series inverter? 5. Disadvantages of series inverter? 41

42 Aim: SERIES INVERTER To study the operation of series inverter and to obtain variable AC from DC input.\ Apparatus Required: i) Series inverter module ii) Loading rheostat - 50 iii) CRO iv) Connection wire series inverter. This unit consists of power circuit and firing circuit sufficient to build and study the modified Circuit Diagram 42

43 Model Graph: t u t e o f T e c h n o l o g y Page 56 Observation Table: A S. No Amplitude (volt) Ton (ms) Toff (ms)

44 Procedure o l o g y Page To begin with switch on the power supply to the firing circuit check that Trigger pulses by varying the frequency. 2. Connections are made as shown in the circuit diagram. 3. Now connect trigger outputs from the firing circuits to gate and cathode of SCRs T1 & T2. 4. Connect DC input from a 30v/2A regulated power supply and switch on the input DC supply. 5. Now apply trigger pulses to SCRs and observe voltage waveform across the load. 6. Measure Vrms & frequency of o/p voltage waveform. Firing Circuit: This part generates two pairs of pulse transformer isolated trigger two SCR s connected as series inverter. ON/OFF switch is provided for the trigger pulses which can be used to switch ON the inverter. Frequency of the inverter can be varied from 100 Hz to 1 KHz approximately. Power Circuit: This part consists of two SCR s two diodes. A center tapped inductor with tappings and 4 capacitors. Input supply terminals with ON/OFF switch and a fuse is provided. All the devices in this unit mounted on a proper heat sink, snubber circuit for dv/dt protection and a fuse in series with each device for short circuit protection. All the points are brought out to front panel for inter connections. They have to be interconnected as shown in the circuit diagram. Fly wheeling diodes can be connected across SCR s and its effect can be observed. Theory: This circuit which converts DC power into AC power is called inverter. If the thyristor commutation circuit of the inverter is in series with the Load, then the inverter is called Series are tightly coupled. In this circuit, it is possible to turn-on-thyristor Tp before the current through thyristor Tn has become zero and vice-versa. Therefore, the Modifed Series Inverter can be operated behond the resonance frequency (fr) of the circuit. Inverter is operated at the resonance frequency (fr) if the load current waveform has low frequency and should not have zero current interval. The inverter s resonance frequency depends on the values of L, R and C in the circuit. 44

45 Front Panel Details: 1. Frequency : Potentiometer to vary the inverter frequency. From 100 Hz to 1 KHz approximately. 2. Gate, Cat : Trigger outputs to connect to Gate and Cathode of SCR 3. ON / OFF : Switch for trigger outputs 4. T1 and T2 : Trigger outputs 5. Power : Mains switch for firing circuit 6. Vdc in : Terminals for DC input 30V/2A max from RPS 7. ON / OFF : Switch for DC input 8. Fuse : Fuse for dc input-2 Amps Glass Fuse 9. T1 and T2 : SCR s TY A / 600V 10. D1 and D2 : Diodes BYQ28. 4A/200V 11. L2, L1, Lm, L1, L2 : 10mH 5mH 0 5mH 10mH/2 Amps 12. C1 and C1 : 6.8 farad / 100V 13. C2 and C2 : 10 farad / 100V 45

46 Result: Thus the operation of a series inverter is studied. 46

47 Post lab questions SERIES INVERTER 1. What is the dead zone of an inverter? 2. Up to what maximum voltage will the capacitor charge during circuit operation? 3. What is the amount of power delivered by capacitor? 4. What is the purpose of coupled inductors in half bridge resonant inverters? 5. Types of resonant pulse inverters? 47

48 EXPT. NO.8: Pre lab questions SPEED CONTROL OF DC MOTOR 1. What type of commutation is applied to Jones Chopper? 2. Give the commutating element to form the commutating circuit for the main thyristor? 3. Give the reason for the high efficiency of this chopper. 48

49 SPEED CONTROL OF DC MOTOR USING 1-PHASE HALF CONTROLLED RECTIFIER Aim: To study the speed control of a dc motor by varying armature applied voltage through phase controlled converter. Apparatus Required: i) DC motor control unit ii) DC ammeter iii) DC voltmeter iv) CRO v) DC motor Circuit Diagram 49

50 DC Motor Speed Control Unit (Power Circuit) 230V/5A This power circuit consists of two SCR s and three diodes. These devices can use to built single phase half wave converter, single phase full wave converter and single phase half controlled bridge converter, and also single phase AC voltage controller power circuits. Each device in the unit is mounted on an appropriate heat sink and is protected by snubber circuit. Short circuit protection is achieved using glass fuses. A circuit breaker is provided in series with the input supply for over load protection and to switch ON/OFF the supply to the power circuit. The Gate and Cathode of each SCR s brought out on the front panel for firing pulse connection. A digital voltmeter and an ammeter is mounted on the front panel to measure the armature voltage and current. All devices schematic is printed on the front panel. Specifications: Input : 10V to 230V single phase SCR : (V) rrm 1200V, (I) av : 10 amps, 25TTS12 International rectifier make. Power diodes & Free Wheeling diode : (V) rrm : 1200V, (I) 16 amps, 12KLR 16DS Fuses : 6 Amps Glass fuses MCB : Two pole 6 amps / 230V Heat Sink : PI-46, 50mm Snubber : R-250 Ohms / 5 Watts c-0.1 Microfarad / 1000V Front Panel Details: AC Input : Terminals to connect 1-phase AC input from single phase isolation transformer. Output : Terminals after the MCB to be connected to power circuit Digital voltmeter : 3 ½ digit voltmeter to measure output voltage Digital ammeter : 3 ½ digital ammeter to measure output voltage Circuit Breaker : 6 Amps, AC power ON/OFF to the circuit and for protection T 1, T 2 : Trigger pulse connections from the firing circuit D 2, D 4 : Power diodes 50

51 D m : Free wheeling diode Field (+and-) : Field supply for DC motor for motor control experiments. (With indicator) Back Panel Details: 3 pin mains socket for AC mains supply to field supply bridge rectifier Glass fuse holders for 6 fuses in series with each SCR s. Procedure: Switch ON the mains supply to the single phase converter firing circuit. Observe the test points and trigger outputs. Verify the trigger outputs and their phase sequence. Vary the firing angle potentiometer and observe the trigger outputs. The pulse train width will increase as we decrease the firing angle from 180 o to 0 o. It is 0 o to 180 o and 50% at 90 o soft start and stop feature is provided for trigger outputs. When we press of ON/OFF switch the trigger outputs will start at 180 o and slowly increased to the firing angle set by firing angle potentiometer. The acceleration time is set in the factor (10 seconds). When we release the ON/OFF switch the trigger outputs will slowly decreased to 180 o from the set firing angle. The deceleration time is set in the factory.(-2 seconds) The deceleration time is very short compared to acceleration time. Make sure that all the trigger outputs are proper before connecting to the power circuits. Make the connections in the power circuit as given in the circuit through isolation transformer. Initially keep the input supply at low voltage say 30 volts. Connect the trigger outputs from firing circuit to the corresponding SCR s Gate and Cathode. Initially connect a Rheostat of 50 Ohms / 5amps. Switch ON the trigger outputs observe the voltage waveforms across load by varying the firing angle potentiometer. Compare with the expected waveforms, if the unit is working properly switch OFF the trigger outputs and switch OFF the MCB. Connect field terminals of DC motor to the field supply points in the power circuit. The connect armature terminal of the DC motor through the rheostat and the rheostat and the ammeter provided in the unit to the output of rectifier. Switch ON the field supply. Set the field voltage to some value 150Volts. This voltage can be measured using the voltmeter provided in the rectifier. Set the input voltage to 100Volts. Initially keep the firing angle pot at 180 o. Initially keep the resistance at maximum position and cut off once the DC motor starts. This is to limit the starting current. Switch On the MCB and trigger outputs. Vary the firing angle potentiometer and note down the output voltage, output current and measure the speed of the 51

52 DC motor for different values of firing angle. Note down these values in the tabular column. And also observe the voltage waveforms. We can observe that back emf will increase as the speed increases. Next vary the input voltage upto 230 volts in steps and note down the readings in the tabular column. Armature Control: S.No. 1 Output Voltage(V) Duty Cycle(%) Frequency Speed(RPM) Current

53 Result: Thus the speed control of DC motor is performed by varying armature voltage through phase controlled converter 53

54 Post lab questions SPEED CONTROL OF DC MOTOR 1. How the load current is smooth other than pulsating? 2. The inductance L maintains the load current to diodes D when SCR T is not conducting. Hence, the motor torque and load current is smooth rather than pulsating. 3. What is the commutating voltage across capacitor C? 4. Give the torque equation for speed control of DC machine. 54

55 EXPT. NO. 9: Pre lab questions SPEED CONTROL OF UNIVERSAL MOTOR: 1. What is universal motor? 2. How speed is controlled by using a thyristor? 3. What is delay angle? 4. What is duty cycle? 5. What is meant by controlled rectifier? 55

56 SPEED CONTROL OF UNIVERSAL MOTOR Aim: To study the speed control of a Universal motor by varying armature applied voltage through phase controlled converter. Apparatus Required: i) Universal kit ii) CRO iii) Batch cards motor iv) Universal motor This unit consists of two parts: (a) Firing circuit and (b) Power circuit Speed Control of Universal Motor Using AC Voltage Control Circuit Diagram: 56

57 Speed control of DC motor using Single phase Half wave converter Speed control of DC motor using Single phase full wave converter Single phase Half controlled bridge rectifier Tabular Column: 57

58 Sl. No. Input Voltage Vin Firing Angle Output Voltage V 0 Output Current I 0 Speed RPM a) Firing Circuit: This unit, generates line synchronized 2 pulse transformer isolated trigger pulses. These trigger pulses can be used to trigger. (i) Single phase AC phase control using SCR s (Antiparallel SCR s) (ii) Single phase AC phase control using triac. (iii) Single phase Half wave rectifier (single SCR) (iv) Single phase Full wave rectifier (Two SCR s) (v) Single phase Half controlled bridge rectifier (Two SCR s & Two diodes) power circuits. The firing circuit is based on zero crossing detector, ramp generator, op-amp comparator and amplifier / pulse transformer isolation method. Front Panel Details: 1. Power : Mains switch for firing circuit with built in indicator 2. Firing angle : Potentiometer to vary the firing angle from 180 o to 0 o 3. SCR / Triac : Selection switch for trigger O/P 1 for SCR/Triac 4. OFF/ON : Switch for trigger O/Ps with soft start feature. 5. Trigger O/Ps : T 1 / T R : T 2 : Trigger O/P for SCR 2 Power Circuit: The power circuit consists of 2 SCR s, 3 diodes and a Triac. The power devices are mounted on suitable heat sink for power dissipation. The snubber circuit is connected for dv/dt protection. A fuse is also provided in series with the devices for short circuit or over current protection. In the input side a 58

59 MCB is provided to switch ON/OFF the supply to the power circuit. A voltmeter and an ammeter is provided to measure the Input / Output voltage and current. Front Panel Details: 1. AC input : Terminals to connect AC input 2. AC output : AC supply terminals after the MCB to be connected to power circuit. 3. MCB : A 6A / 2 pole MCB for ON/OFF the AC supply to the power circuit 4. T 1 & T 2 : SCR s 16 Amps / 600 volts 5. D 3 & D 4 : Diodes 16amps / 600V 6. D m : Free wheeling diode 7. T R : Triac 10 amps / 600 volts 8. Voltmeter : 3 ½ Digit digital AC/DC Voltmeter to measure input / output voltage 9. Ammeter : 3 ½ Digit digital AC/DC Ammeter to measure current Procedure: Make the inter connections in the power circuit as given is the circuit diagram. Switch ON the firing circuit and observe the trigger outputs. Make sure that the firing pulses are proper before connecting to the power circuit. Then connect the trigger output from firing circuit to corresponding SCR s / Triac. In the power circuit Initially set the AC input to 30 volts. Switch ON and MCB. Switch ON the Trigger outputs switch. Select the SCR / Triac selection switch and observe the output wave forms across R load by varying the firing angle potentiometer. If the output wave form is proper then you can connect the motor & increase the input voltage to rated value 0-230V gradually. Vary the firing angle and note down output voltage and speed of the motor. Note: 1) If you are not getting the output after all proper connections interchange AC output terminals, after switch OFF the MCB. This is just to synchronize the power circuit with firing circuit. 59

60 Result: Thus the speed control of Universal motor is performed by varying armature voltage through phase controlled converter 60

61 Post lab questions SPEED CONTROL OF UNIVERSAL MOTOR 1. What is Circuit Breaker & Fuse? 2. What are the different operating regions of SCR? 3. What is gate pulse? 4. What is snubber circuit? 5. Different methods of speed control? 61

62 EXPT. NO.12: Pre lab questions VOLTAGE COMMUTATED CHOPPER 1. What are the other names of this circuit? 2. What are the commutating components of this circuit? 3. What are the different types of commutated choppers? 4. Give the expression for commutating elements L and C for the voltage commutated chopper. 5. What is the purpose of freewheeling diode? 62

63 VOLTAGE COMMUTATED CHOPPER Aim: To observe the operation of class D commutated technique. Apparatus Required: 1. Force commutation trainer kit. 2. Patch chord 3. CRO CIRCUIT DIAGRAM 63

64 Model Graph: Tabular Column: S.No. Duty Cycle(%) Output Voltage(V) Time period(ms) Procedure: 1) Patch the voltage commutated chopper as per the circuit diagram 2) Connect the CRO probe across the commutated chopper 3) Give the input dc voltage (0-30)v, 2amps from the external power supply. 4) Switch ON the trainer then switch ON the input dc suuply circuit breaker. 5) After then switch ON the trigger OFF-ON position 6) From the capacitor output waveform we can measure the turn on time and turn off time of main SCR as well as auxiliary SCR 7) Verify the unity and frequency of the triggering circuit using parts provided on the triggering circuit. 64

65 8) Also observe the voltage across main SCR and auxiliary SCR and load 9) Take the turn on and turn off time at main so auxiliary SCR from the capacitor waveform at various values of unity cycle and frequency and tabulate them 10) Also find out the peak value of current through the capacitor Theory: MODE-1 Main SCR is triggered to make source current to flow in two path one is load current and other path with triggering of SCR load get connected to supply and load voltage. MODE-2 At a desired instant the auxiliary SCR is to be triggered for turning OFF the main SCR T1 with the switch ON, T2 reverse capacitance voltage appears across T1 which reverse biases it and turn it OFF. MODE-3 SCR T2 turn OFF since the capacitance is slightly changed after the freewheeling diode set frequently forward biased. 65

66 Result: Thus the operation of class D commutated technique has been obtained. 66

67 Post lab questions VOLTAGE COMMUTATED CHOPPER 1. What are the initial conditions to be attained before the circuit can be operated? 2. What are the components required for commutating the thyristor? 3. What is the main disadvantage of this circuit? 4. In what mode does the diode and inductor operate? 5. Give the classification of the choppers. 67

68 68

69 69

The full wave rectifier consists of two diodes and a resister as shown in Figure

The full wave rectifier consists of two diodes and a resister as shown in Figure The Full-Wave Rectifier The full wave rectifier consists of two diodes and a resister as shown in Figure The transformer has a centre-tapped secondary winding. This secondary winding has a lead attached

More information

Power Supplies. 1.0 Power Supply Basics. www.learnabout-electronics.org. Module

Power Supplies. 1.0 Power Supply Basics. www.learnabout-electronics.org. Module Module 1 www.learnabout-electronics.org Power Supplies 1.0 Power Supply Basics What you ll learn in Module 1 Section 1.0 Power Supply Basics. Basic functions of a power supply. Safety aspects of working

More information

Silicon Controlled Rectifiers

Silicon Controlled Rectifiers 554 20 Principles of Electronics Silicon Controlled Rectifiers 20.1 Silicon Controlled Rectifier (SCR) 20.2 Working of SCR 20.3 Equivalent Circuit of SCR 20.4 Important Terms 20.5 V-I Characteristics of

More information

FREQUENCY CONTROLLED AC MOTOR DRIVE

FREQUENCY CONTROLLED AC MOTOR DRIVE FREQUENCY CONTROLLED AC MOTOR DRIVE 1.0 Features of Standard AC Motors The squirrel cage induction motor is the electrical motor motor type most widely used in industry. This leading position results mainly

More information

LM 358 Op Amp. If you have small signals and need a more useful reading we could amplify it using the op amp, this is commonly used in sensors.

LM 358 Op Amp. If you have small signals and need a more useful reading we could amplify it using the op amp, this is commonly used in sensors. LM 358 Op Amp S k i l l L e v e l : I n t e r m e d i a t e OVERVIEW The LM 358 is a duel single supply operational amplifier. As it is a single supply it eliminates the need for a duel power supply, thus

More information

Properties of electrical signals

Properties of electrical signals DC Voltage Component (Average voltage) Properties of electrical signals v(t) = V DC + v ac (t) V DC is the voltage value displayed on a DC voltmeter Triangular waveform DC component Half-wave rectifier

More information

Rectifier circuits & DC power supplies

Rectifier circuits & DC power supplies Rectifier circuits & DC power supplies Goal: Generate the DC voltages needed for most electronics starting with the AC power that comes through the power line? 120 V RMS f = 60 Hz T = 1667 ms) = )sin How

More information

Diode Applications. As we have already seen the diode can act as a switch Forward biased or reverse biased - On or Off.

Diode Applications. As we have already seen the diode can act as a switch Forward biased or reverse biased - On or Off. Diode Applications Diode Switching As we have already seen the diode can act as a switch Forward biased or reverse biased - On or Off. Voltage Rectifier A voltage rectifier is a circuit that converts an

More information

Chapter 3. Diodes and Applications. Introduction [5], [6]

Chapter 3. Diodes and Applications. Introduction [5], [6] Chapter 3 Diodes and Applications Introduction [5], [6] Diode is the most basic of semiconductor device. It should be noted that the term of diode refers to the basic p-n junction diode. All other diode

More information

DIODE CIRCUITS LABORATORY. Fig. 8.1a Fig 8.1b

DIODE CIRCUITS LABORATORY. Fig. 8.1a Fig 8.1b DIODE CIRCUITS LABORATORY A solid state diode consists of a junction of either dissimilar semiconductors (pn junction diode) or a metal and a semiconductor (Schottky barrier diode). Regardless of the type,

More information

ANADOLU UNIVERSITY DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

ANADOLU UNIVERSITY DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING ANADOLU UNIVERSITY DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING EEM 102 INTRODUCTION TO ELECTRICAL ENGINEERING EXPERIMENT 9: DIODES AND DC POWER SUPPLY OBJECTIVE: To observe how a diode functions

More information

Lecture - 4 Diode Rectifier Circuits

Lecture - 4 Diode Rectifier Circuits Basic Electronics (Module 1 Semiconductor Diodes) Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati Lecture - 4 Diode Rectifier Circuits

More information

Precision Diode Rectifiers

Precision Diode Rectifiers by Kenneth A. Kuhn March 21, 2013 Precision half-wave rectifiers An operational amplifier can be used to linearize a non-linear function such as the transfer function of a semiconductor diode. The classic

More information

The D.C Power Supply

The D.C Power Supply The D.C Power Supply Voltage Step Down Electrical Isolation Converts Bipolar signal to Unipolar Half or Full wave Smoothes the voltage variation Still has some ripples Reduce ripples Stabilize the output

More information

See Horenstein 4.3 and 4.4

See Horenstein 4.3 and 4.4 EE 462: Laboratory # 4 DC Power Supply Circuits Using Diodes by Drs. A.V. Radun and K.D. Donohue (2/14/07) Department of Electrical and Computer Engineering University of Kentucky Lexington, KY 40506 Updated

More information

Diode Applications. by Kenneth A. Kuhn Sept. 1, 2008. This note illustrates some common applications of diodes.

Diode Applications. by Kenneth A. Kuhn Sept. 1, 2008. This note illustrates some common applications of diodes. by Kenneth A. Kuhn Sept. 1, 2008 This note illustrates some common applications of diodes. Power supply applications A common application for diodes is converting AC to DC. Although half-wave rectification

More information

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT 4 Understand single-phase alternating current (ac) theory Single phase AC

More information

SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS

SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES After studying this unit, the reader should be able to Describe the different types of open single-phase motors used to drive

More information

AC Direct Off-Line Power Supplies

AC Direct Off-Line Power Supplies AC Direct Off-Line Power Supplies r Introduction Many DC power supplies found in electronic systems, including those in this Tech School, rectify the 120 volts available at an electric outlet. The initial

More information

LABORATORY 10 TIME AVERAGES, RMS VALUES AND THE BRIDGE RECTIFIER. Bridge Rectifier

LABORATORY 10 TIME AVERAGES, RMS VALUES AND THE BRIDGE RECTIFIER. Bridge Rectifier LABORATORY 10 TIME AVERAGES, RMS VALUES AND THE BRIDGE RECTIFIER Full-wave Rectification: Bridge Rectifier For many electronic circuits, DC supply voltages are required but only AC voltages are available.

More information

= V peak 2 = 0.707V peak

= V peak 2 = 0.707V peak BASIC ELECTRONICS - RECTIFICATION AND FILTERING PURPOSE Suppose that you wanted to build a simple DC electronic power supply, which operated off of an AC input (e.g., something you might plug into a standard

More information

CYCLOCONVERTERS. Fig.1 Block diagram of a cycloconverter

CYCLOCONVERTERS. Fig.1 Block diagram of a cycloconverter CYCLOCONVERTERS Burak Ozpineci, Leon M. Tolbert Department of Electrical and Computer Engineering University of Tennessee-Knoxville Knoxville, TN 37996-2100 In industrial applications, two forms of electrical

More information

Principles of Adjustable Frequency Drives

Principles of Adjustable Frequency Drives What is an Adjustable Frequency Drive? An adjustable frequency drive is a system for controlling the speed of an AC motor by controlling the frequency of the power supplied to the motor. A basic adjustable

More information

Yrd. Doç. Dr. Aytaç Gören

Yrd. Doç. Dr. Aytaç Gören H2 - AC to DC Yrd. Doç. Dr. Aytaç Gören ELK 2018 - Contents W01 Basic Concepts in Electronics W02 AC to DC Conversion W03 Analysis of DC Circuits W04 Transistors and Applications (H-Bridge) W05 Op Amps

More information

Power Electronics. Prof. K. Gopakumar. Centre for Electronics Design and Technology. Indian Institute of Science, Bangalore.

Power Electronics. Prof. K. Gopakumar. Centre for Electronics Design and Technology. Indian Institute of Science, Bangalore. Power Electronics Prof. K. Gopakumar Centre for Electronics Design and Technology Indian Institute of Science, Bangalore Lecture - 1 Electric Drive Today, we will start with the topic on industrial drive

More information

Chapter 22 Further Electronics

Chapter 22 Further Electronics hapter 22 Further Electronics washing machine has a delay on the door opening after a cycle of washing. Part of this circuit is shown below. s the cycle ends, switch S closes. t this stage the capacitor

More information

Thyristor & Power Control Circuits

Thyristor & Power Control Circuits Student Workbook 91570-00 Edition 4 Ê>{YèèRÆ3ÇË 3091570000503 FOURTH EDITION Second Printing, March 2005 Copyright February, 2003 Lab-Volt Systems, Inc. All rights reserved. No part of this publication

More information

Line Reactors and AC Drives

Line Reactors and AC Drives Line Reactors and AC Drives Rockwell Automation Mequon Wisconsin Quite often, line and load reactors are installed on AC drives without a solid understanding of why or what the positive and negative consequences

More information

ULRASONIC GENERATOR POWER CIRCUITRY. Will it fit on PC board

ULRASONIC GENERATOR POWER CIRCUITRY. Will it fit on PC board ULRASONIC GENERATOR POWER CIRCUITRY Will it fit on PC board MAJOR COMPONENTS HIGH POWER FACTOR RECTIFIER RECTIFIES POWER LINE RAIL SUPPLY SETS VOLTAGE AMPLITUDE INVERTER INVERTS RAIL VOLTAGE FILTER FILTERS

More information

EET272 Worksheet Week 9

EET272 Worksheet Week 9 EET272 Worksheet Week 9 answer questions 1-5 in preparation for discussion for the quiz on Monday. Finish the rest of the questions for discussion in class on Wednesday. Question 1 Questions AC s are becoming

More information

Fundamental Characteristics of Thyristors

Fundamental Characteristics of Thyristors A1001 Introduction The Thyristor family of semiconductors consists of several very useful devices. The most widely used of this family are silicon controlled rectifiers (SCRs), Triacs, SIDACs, and DIACs.

More information

POWER SUPPLY MODEL XP-15. Instruction Manual ELENCO

POWER SUPPLY MODEL XP-15. Instruction Manual ELENCO POWER SUPPLY MODEL XP-15 Instruction Manual ELENCO Copyright 2013 by Elenco Electronics, Inc. REV-A 753020 All rights reserved. No part of this book shall be reproduced by any means; electronic, photocopying,

More information

Application Note AN- 1095

Application Note AN- 1095 Application Note AN- 1095 Design of the Inverter Output Filter for Motor Drives with IRAMS Power Modules Cesare Bocchiola Table of Contents Page Section 1: Introduction...2 Section 2 : Output Filter Design

More information

Semiconductor Diode. It has already been discussed in the previous chapter that a pn junction conducts current easily. Principles of Electronics

Semiconductor Diode. It has already been discussed in the previous chapter that a pn junction conducts current easily. Principles of Electronics 76 6 Principles of Electronics Semiconductor Diode 6.1 Semiconductor Diode 6.3 Resistance of Crystal Diode 6.5 Crystal Diode Equivalent Circuits 6.7 Crystal Diode Rectifiers 6.9 Output Frequency of Half-Wave

More information

Chapter 4 AC to AC Converters ( AC Controllers and Frequency Converters )

Chapter 4 AC to AC Converters ( AC Controllers and Frequency Converters ) Chapter 4 AC to AC Converters ( AC Controllers and Frequency Converters ) Classification of AC to AC converters Same frequency variable magnitude AC power AC controllers AC power Frequency converters (Cycloconverters)

More information

Transformerless UPS systems and the 9900 By: John Steele, EIT Engineering Manager

Transformerless UPS systems and the 9900 By: John Steele, EIT Engineering Manager Transformerless UPS systems and the 9900 By: John Steele, EIT Engineering Manager Introduction There is a growing trend in the UPS industry to create a highly efficient, more lightweight and smaller UPS

More information

Module 1. Power Semiconductor Devices. Version 2 EE IIT, Kharagpur 1

Module 1. Power Semiconductor Devices. Version 2 EE IIT, Kharagpur 1 Module 1 Power Semiconductor Devices Version 2 EE IIT, Kharagpur 1 Lesson 4 Thyristors and Triacs Version 2 EE IIT, Kharagpur 2 Instructional objects On completion the student will be able to Explain the

More information

What Is Regeneration?

What Is Regeneration? What Is Regeneration? Braking / Regeneration Manual Regeneration Overview Revision 1.0 When the rotor of an induction motor turns slower than the speed set by the applied frequency, the motor is transforming

More information

Operational Amplifier - IC 741

Operational Amplifier - IC 741 Operational Amplifier - IC 741 Tabish December 2005 Aim: To study the working of an 741 operational amplifier by conducting the following experiments: (a) Input bias current measurement (b) Input offset

More information

BSNL TTA Question Paper-Instruments and Measurement Specialization 2007

BSNL TTA Question Paper-Instruments and Measurement Specialization 2007 BSNL TTA Question Paper-Instruments and Measurement Specialization 2007 (1) Instrument is a device for determining (a) the magnitude of a quantity (b) the physics of a variable (c) either of the above

More information

7-41 POWER FACTOR CORRECTION

7-41 POWER FACTOR CORRECTION POWER FTOR CORRECTION INTRODUCTION Modern electronic equipment can create noise that will cause problems with other equipment on the same supply system. To reduce system disturbances it is therefore essential

More information

ECEN 1400, Introduction to Analog and Digital Electronics

ECEN 1400, Introduction to Analog and Digital Electronics ECEN 1400, Introduction to Analog and Digital Electronics Lab 4: Power supply 1 INTRODUCTION This lab will span two lab periods. In this lab, you will create the power supply that transforms the AC wall

More information

electronics fundamentals

electronics fundamentals electronics fundamentals circuits, devices, and applications THOMAS L. FLOYD DAVID M. BUCHLA Lesson 1: Diodes and Applications Center-Tapped Full-wave Rectifier The center-tapped (CT) full-wave rectifier

More information

Type SA-1 Generator Differential Relay

Type SA-1 Generator Differential Relay ABB Automation Inc. Substation Automation and Protection Division Coral Springs, FL 33065 Instruction Leaflet 41-348.11C Effective: November 1999 Supersedes I.L. 41-348.11B, Dated August 1986 ( ) Denotes

More information

OPERATIONAL AMPLIFIERS. o/p

OPERATIONAL AMPLIFIERS. o/p OPERATIONAL AMPLIFIERS 1. If the input to the circuit of figure is a sine wave the output will be i/p o/p a. A half wave rectified sine wave b. A fullwave rectified sine wave c. A triangular wave d. A

More information

DIRECT CURRENT GENERATORS

DIRECT CURRENT GENERATORS DIRECT CURRENT GENERATORS Revision 12:50 14 Nov 05 INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy by using the principle of magnetic induction. This principle

More information

Building the HVPS High Voltage Power Supply

Building the HVPS High Voltage Power Supply Introduction Building the HVPS High Voltage Power Supply Voltages higher than the LVPS provides kilovolts are needed in later experiments to get strong electric fields and to generate microwaves. The high-voltage

More information

Inductors in AC Circuits

Inductors in AC Circuits Inductors in AC Circuits Name Section Resistors, inductors, and capacitors all have the effect of modifying the size of the current in an AC circuit and the time at which the current reaches its maximum

More information

2. A conductor of length 2m moves at 4m/s at 30 to a uniform magnetic field of 0.1T. Which one of the following gives the e.m.f. generated?

2. A conductor of length 2m moves at 4m/s at 30 to a uniform magnetic field of 0.1T. Which one of the following gives the e.m.f. generated? Extra Questions - 2 1. A straight length of wire moves through a uniform magnetic field. The e.m.f. produced across the ends of the wire will be maximum if it moves: a) along the lines of magnetic flux

More information

Experiment 2 Diode Applications: Rectifiers

Experiment 2 Diode Applications: Rectifiers ECE 3550 - Practicum Fall 2007 Experiment 2 Diode Applications: Rectifiers Objectives 1. To investigate the characteristics of half-wave and full-wave rectifier circuits. 2. To recognize the usefulness

More information

AMZ-FX Guitar effects. (2007) Mosfet Body Diodes. http://www.muzique.com/news/mosfet-body-diodes/. Accessed 22/12/09.

AMZ-FX Guitar effects. (2007) Mosfet Body Diodes. http://www.muzique.com/news/mosfet-body-diodes/. Accessed 22/12/09. Pulse width modulation Pulse width modulation is a pulsed DC square wave, commonly used to control the on-off switching of a silicon controlled rectifier via the gate. There are many types of SCR s, most

More information

Unit/Standard Number. High School Graduation Years 2010, 2011 and 2012

Unit/Standard Number. High School Graduation Years 2010, 2011 and 2012 1 Secondary Task List 100 SAFETY 101 Demonstrate an understanding of State and School safety regulations. 102 Practice safety techniques for electronics work. 103 Demonstrate an understanding of proper

More information

Product Data Bulletin

Product Data Bulletin Product Data Bulletin Power System Harmonics Causes and Effects of Variable Frequency Drives Relative to the IEEE 519-1992 Standard Raleigh, NC, U.S.A. INTRODUCTION This document describes power system

More information

Chapter 4. LLC Resonant Converter

Chapter 4. LLC Resonant Converter Chapter 4 LLC Resonant Converter 4.1 Introduction In previous chapters, the trends and technical challenges for front end DC/DC converter were discussed. High power density, high efficiency and high power

More information

EE362L, Power Electronics Triac Light Dimmer

EE362L, Power Electronics Triac Light Dimmer 1 EE362L, Power Electronics Triac Light Dimmer Rochelle Stortz and Brian Taraba, Team 277 2/2/05 Abstract - This document presents the construction of a light dimmer circuit that utilizes the current-regulating

More information

Variable Frequency Drives - a Comparison of VSI versus LCI Systems

Variable Frequency Drives - a Comparison of VSI versus LCI Systems Variable Frequency Drives - a Comparison of VSI versus LCI Systems Introduction TMEIC is a leader in the innovative design and manufacture of large ac variable f requency drive systems. TMEIC has been

More information

GenTech Practice Questions

GenTech Practice Questions GenTech Practice Questions Basic Electronics Test: This test will assess your knowledge of and ability to apply the principles of Basic Electronics. This test is comprised of 90 questions in the following

More information

GLOLAB Two Wire Stepper Motor Positioner

GLOLAB Two Wire Stepper Motor Positioner Introduction A simple and inexpensive way to remotely rotate a display or object is with a positioner that uses a stepper motor to rotate it. The motor is driven by a circuit mounted near the motor and

More information

Design Considerations for an LLC Resonant Converter

Design Considerations for an LLC Resonant Converter Design Considerations for an LLC Resonant Converter Hangseok Choi Power Conversion Team www.fairchildsemi.com 1. Introduction Growing demand for higher power density and low profile in power converter

More information

Pulse Width Modulation (PWM) LED Dimmer Circuit. Using a 555 Timer Chip

Pulse Width Modulation (PWM) LED Dimmer Circuit. Using a 555 Timer Chip Pulse Width Modulation (PWM) LED Dimmer Circuit Using a 555 Timer Chip Goals of Experiment Demonstrate the operation of a simple PWM circuit that can be used to adjust the intensity of a green LED by varying

More information

Analog & Digital Electronics Course No: PH-218

Analog & Digital Electronics Course No: PH-218 Analog & Digital Electronics Course No: PH-18 Lec 3: Rectifier and Clipper circuits Course nstructors: Dr. A. P. VAJPEY Department of Physics, ndian nstitute of Technology Guwahati, ndia 1 Rectifier Circuits:

More information

EE 1202 Experiment #4 Capacitors, Inductors, and Transient Circuits

EE 1202 Experiment #4 Capacitors, Inductors, and Transient Circuits EE 1202 Experiment #4 Capacitors, Inductors, and Transient Circuits 1. Introduction and Goal: Exploring transient behavior due to inductors and capacitors in DC circuits; gaining experience with lab instruments.

More information

DC Motor control Reversing

DC Motor control Reversing January 2013 DC Motor control Reversing and a "Rotor" which is the rotating part. Basically there are three types of DC Motor available: - Brushed Motor - Brushless Motor - Stepper Motor DC motors Electrical

More information

Frequency Response of Filters

Frequency Response of Filters School of Engineering Department of Electrical and Computer Engineering 332:224 Principles of Electrical Engineering II Laboratory Experiment 2 Frequency Response of Filters 1 Introduction Objectives To

More information

Circuits with inductors and alternating currents. Chapter 20 #45, 46, 47, 49

Circuits with inductors and alternating currents. Chapter 20 #45, 46, 47, 49 Circuits with inductors and alternating currents Chapter 20 #45, 46, 47, 49 RL circuits Ch. 20 (last section) Symbol for inductor looks like a spring. An inductor is a circuit element that has a large

More information

Episode 126: Capacitance and the equation C =Q/V

Episode 126: Capacitance and the equation C =Q/V Episode 126: Capacitance and the equation C =Q/V Having established that there is charge on each capacitor plate, the next stage is to establish the relationship between charge and potential difference

More information

ENGR-4300 Electronic Instrumentation Quiz 4 Spring 2011 Name Section

ENGR-4300 Electronic Instrumentation Quiz 4 Spring 2011 Name Section ENGR-4300 Electronic Instrumentation Quiz 4 Spring 2011 Name Section Question I (20 points) Question II (20 points) Question III (20 points) Question IV (20 points) Question V (20 points) Total (100 points)

More information

CONSTRUCTING A VARIABLE POWER SUPPLY UNIT

CONSTRUCTING A VARIABLE POWER SUPPLY UNIT CONSTRUCTING A VARIABLE POWER SUPPLY UNIT Building a power supply is a good way to put into practice many of the ideas we have been studying about electrical power so far. Most often, power supplies are

More information

ε: Voltage output of Signal Generator (also called the Source voltage or Applied

ε: Voltage output of Signal Generator (also called the Source voltage or Applied Experiment #10: LR & RC Circuits Frequency Response EQUIPMENT NEEDED Science Workshop Interface Power Amplifier (2) Voltage Sensor graph paper (optional) (3) Patch Cords Decade resistor, capacitor, and

More information

Drive circuit basics + V. τ e. Industrial Circuits Application Note. Winding resistance and inductance

Drive circuit basics + V. τ e. Industrial Circuits Application Note. Winding resistance and inductance ndustrial Circuits Application Note Drive circuit basics For a given size of a stepper motor, a limited space is available for the windings. n the process of optimizing a stepper motor drive system, an

More information

Wires & Connections Component Circuit Symbol Function of Component. Power Supplies Component Circuit Symbol Function of Component

Wires & Connections Component Circuit Symbol Function of Component. Power Supplies Component Circuit Symbol Function of Component Lista Dei Simboli Dei Circuiti Per i Componenti Elettronici Wires & Connections Wire Wires joined Wires not joined To pass current very easily from one part of a circuit to another. A 'blob' should be

More information

Content Map For Career & Technology

Content Map For Career & Technology Content Strand: Applied Academics CT-ET1-1 analysis of electronic A. Fractions and decimals B. Powers of 10 and engineering notation C. Formula based problem solutions D. Powers and roots E. Linear equations

More information

Relationship between large subject matter areas

Relationship between large subject matter areas H02M APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER;

More information

Introduction to Power Supplies

Introduction to Power Supplies Introduction to Power Supplies INTRODUCTION Virtually every piece of electronic equipment e g computers and their peripherals calculators TV and hi-fi equipment and instruments is powered from a DC power

More information

Renewable Energy Laboratory for Engineering Students

Renewable Energy Laboratory for Engineering Students dspace User Conference 2010 India Sept 24 th 10 Renewable Energy Laboratory for Engineering Students H.T Jadhav, S. D. Joshi Rajarambapu Institute Of Technology ABSTRACT Renewal Energy is now included

More information

12. Transformers, Impedance Matching and Maximum Power Transfer

12. Transformers, Impedance Matching and Maximum Power Transfer 1 1. Transformers, Impedance Matching and Maximum Power Transfer Introduction The transformer is a device that takes AC at one voltage and transforms it into another voltage either higher or lower than

More information

ENGINEERING COMMITTEE Interface Practices Subcommittee AMERICAN NATIONAL STANDARD ANSI/SCTE 46 2007. Test Method for AC to DC Power Supplies

ENGINEERING COMMITTEE Interface Practices Subcommittee AMERICAN NATIONAL STANDARD ANSI/SCTE 46 2007. Test Method for AC to DC Power Supplies ENGINEERING COMMITTEE Interface Practices Subcommittee AMERICAN NATIONAL STANDARD ANSI/SCTE 46 2007 Test Method for AC to DC Power Supplies NOTICE The Society of Cable Telecommunications Engineers (SCTE)

More information

VOLTAGE REGULATOR AND PARALLEL OPERATION

VOLTAGE REGULATOR AND PARALLEL OPERATION VOLTAGE REGULATOR AND PARALLEL OPERATION Generator sets are operated in parallel to improve fuel economy and reliability of the power supply. Economy is improved with multiple paralleled generators by

More information

AN ULTRA-CHEAP GRID CONNECTED INVERTER FOR SMALL SCALE GRID CONNECTION

AN ULTRA-CHEAP GRID CONNECTED INVERTER FOR SMALL SCALE GRID CONNECTION AN ULTRA-CHEAP GRID CONNECTED INVERTER FOR SMALL SCALE GRID CONNECTION Pramod Ghimire 1, Dr. Alan R. Wood 2 1 ME Candidate Email: pgh56@student.canterbury.ac.nz 2 Senior Lecturer: Canterbury University

More information

Lab 14: 3-phase alternator.

Lab 14: 3-phase alternator. Lab 14: 3-phase alternator. Objective: to obtain the no-load saturation curve of the alternator; to determine the voltage regulation characteristic of the alternator with resistive, capacitive, and inductive

More information

UNIVERSITY OF WATERLOO ELECTRICAL & COMPUTER ENGINEERING DEPARTMENT ME269 ELECTROMECHANICAL DEVICES AND POWER PROCESSING.

UNIVERSITY OF WATERLOO ELECTRICAL & COMPUTER ENGINEERING DEPARTMENT ME269 ELECTROMECHANICAL DEVICES AND POWER PROCESSING. UNIVERSITY OF WATERLOO ELECTRICAL & COMPUTER ENGINEERING DEPARTMENT ME269 ELECTROMECHANICAL DEVICES AND POWER PROCESSING. Group # First Name Last Name UserID @uwaterloo.ca Experiment #3: DIRECT CURRENT

More information

Electrical Fundamentals Module 3: Parallel Circuits

Electrical Fundamentals Module 3: Parallel Circuits Electrical Fundamentals Module 3: Parallel Circuits PREPARED BY IAT Curriculum Unit August 2008 Institute of Applied Technology, 2008 ATE310- Electrical Fundamentals 2 Module 3 Parallel Circuits Module

More information

Power measurement in balanced 3 phase circuits and power factor improvement. 1 Power in Single Phase Circuits. Experiment no 1

Power measurement in balanced 3 phase circuits and power factor improvement. 1 Power in Single Phase Circuits. Experiment no 1 Experiment no 1 Power measurement in balanced 3 phase circuits and power factor improvement 1 Power in Single Phase Circuits Let v = m cos(ωt) = cos(ωt) is the voltage applied to a R-L circuit and i =

More information

TEA1024/ TEA1124. Zero Voltage Switch with Fixed Ramp. Description. Features. Block Diagram

TEA1024/ TEA1124. Zero Voltage Switch with Fixed Ramp. Description. Features. Block Diagram Zero Voltage Switch with Fixed Ramp TEA04/ TEA4 Description The monolithic integrated bipolar circuit, TEA04/ TEA4 is a zero voltage switch for triac control in domestic equipments. It offers not only

More information

The 2N3393 Bipolar Junction Transistor

The 2N3393 Bipolar Junction Transistor The 2N3393 Bipolar Junction Transistor Common-Emitter Amplifier Aaron Prust Abstract The bipolar junction transistor (BJT) is a non-linear electronic device which can be used for amplification and switching.

More information

Equipment: Power Supply, DAI, Transformer (8341), Variable resistance (8311), Variable inductance (8321), Variable capacitance (8331)

Equipment: Power Supply, DAI, Transformer (8341), Variable resistance (8311), Variable inductance (8321), Variable capacitance (8331) Lab 5: Single-phase transformer operations. Objective: to examine the design of single-phase transformers; to study the voltage and current ratios of transformers; to study the voltage regulation of the

More information

Equipment: Power Supply, DAI, Synchronous motor (8241), Electrodynamometer (8960), Tachometer, Timing belt.

Equipment: Power Supply, DAI, Synchronous motor (8241), Electrodynamometer (8960), Tachometer, Timing belt. Lab 9: Synchronous motor. Objective: to examine the design of a 3-phase synchronous motor; to learn how to connect it; to obtain its starting characteristic; to determine the full-load characteristic of

More information

PowerFlex Dynamic Braking Resistor Calculator

PowerFlex Dynamic Braking Resistor Calculator Application Technique PowerFlex Dynamic Braking Resistor Calculator Catalog Numbers 20A, 20B, 20F, 20G, 22A, 22B Important User Information Solid-state equipment has operational characteristics differing

More information

Lab 1 Diode Characteristics

Lab 1 Diode Characteristics Lab 1 Diode Characteristics Purpose The purpose of this lab is to study the characteristics of the diode. Some of the characteristics that will be investigated are the I-V curve and the rectification properties.

More information

Transistor Amplifiers

Transistor Amplifiers Physics 3330 Experiment #7 Fall 1999 Transistor Amplifiers Purpose The aim of this experiment is to develop a bipolar transistor amplifier with a voltage gain of minus 25. The amplifier must accept input

More information

CATHODIC PROTECTION TRANSFORMER RECTIFIER (CPTR)

CATHODIC PROTECTION TRANSFORMER RECTIFIER (CPTR) CATHODIC PROTECTION TRANSFORMER RECTIFIER (CPTR) Fig1. CPTR SMART CONTROL PRECISION CUSTOMIZED MANUAL OR AUTO SCR OR DIODE DRY TYPE SWITCH MODE DRY TYPE SCR OR DIODE OIL TYPE 1 INDEX PAGE 1. Cover 2. Index

More information

BASIC ELECTRONICS AC CIRCUIT ANALYSIS. December 2011

BASIC ELECTRONICS AC CIRCUIT ANALYSIS. December 2011 AM 5-202 BASIC ELECTRONICS AC CIRCUIT ANALYSIS December 2011 DISTRIBUTION RESTRICTION: Approved for Pubic Release. Distribution is unlimited. DEPARTMENT OF THE ARMY MILITARY AUXILIARY RADIO SYSTEM FORT

More information

CHAPTER 2B: DIODE AND APPLICATIONS. D.Wilcher

CHAPTER 2B: DIODE AND APPLICATIONS. D.Wilcher CHAPTER 2B: DIODE AND APPLICATIONS D.Wilcher 1 CHAPTER 2B: OBJECTIVES Analyze the operation of 3 basic types of rectifiers Describe the operation of rectifier filters and IC regulators Analyze the operation

More information

New High Current MOSFET Module Offers 177 µω R DS(on)

New High Current MOSFET Module Offers 177 µω R DS(on) ew High Current Offers 177 µω R D(on) By William C. Kephart, Eric R. Motto Application Engineering owerex Incorporated Abstract This paper describes a new family of high current modules optimized for industrial

More information

Current and Temperature Ratings

Current and Temperature Ratings Document 361-1 Current and Temperature Ratings Introduction This application note describes: How to interpret Coilcraft inductor current and temperature ratings Our current ratings measurement method and

More information

Kit 106. 50 Watt Audio Amplifier

Kit 106. 50 Watt Audio Amplifier Kit 106 50 Watt Audio Amplifier T his kit is based on an amazing IC amplifier module from ST Electronics, the TDA7294 It is intended for use as a high quality audio class AB amplifier in hi-fi applications

More information

Lab 3 Rectifier Circuits

Lab 3 Rectifier Circuits ECET 242 Electronic Circuits Lab 3 Rectifier Circuits Page 1 of 5 Name: Objective: Students successfully completing this lab exercise will accomplish the following objectives: 1. Learn how to construct

More information

Apprentice Telecommunications Technician Test (CTT) Study Guide

Apprentice Telecommunications Technician Test (CTT) Study Guide Apprentice Telecommunications Technician Test (CTT) Study Guide 1 05/2014 Study Guide for Pacific Gas & Electric Company Apprentice Telecommunications Technician Qualifying Test (CTT) About the Test The

More information

Chapter 2 MENJANA MINDA KREATIF DAN INOVATIF

Chapter 2 MENJANA MINDA KREATIF DAN INOVATIF Chapter 2 DIODE part 2 MENJANA MINDA KREATIF DAN INOATIF objectives Diode with DC supply circuit analysis serial & parallel Diode d applications the DC power supply & Clipper Analysis & Design of rectifier

More information

High voltage power supply (1 to 20 KV)

High voltage power supply (1 to 20 KV) High voltage power supply ( to 0 KV) Ammar Ahmed Khan, Muhammad Wasif, Muhammad Sabieh Anwar This documentation is divided into two parts, the first part provides a brief overview about the key features

More information