Electricity and New Energy Three-Phase Induction Motor Starters Courseware Sample 88197-F0
Safety and Common Symbols Caution, risk of danger Festo Didactic 88197-10 III
Safety and Common Symbols IV Festo Didactic 88197-10
Table of Contents Festo Didactic 88197-10 V
Table of Contents VI Festo Didactic 88197-10
Preface Festo Didactic 88197-10 VII
Preface VIII Festo Didactic 88197-10
About This Manual Manual objectives Safety considerations Prerequisite DC Power Circuits Single-Phase AC Power Circuits Three-Phase AC Power Circuits Three-Phase Rotating Machines Systems of units Festo Didactic 88197-10 IX
To the Instructor Accuracy of measurements Equipment installation Festo Didactic 88197-10 XI
Sample Exercise Extracted from the Student Manual and the Instructor Guide
Exercise 1 DOL Starters and Soft Starters EXERCISE OBJECTIVE DISCUSSION OUTLINE Overcurrent protection. Overload protection. Start up current. Consequences of extended large currents. Voltage sag. Start-up torque. Voltage output of a soft starter. Effect of the soft starter on the motor current. Effect of the soft starter on the motor torque. Effect of the soft starter on the motor speed. How a soft starter controls voltage. Bypass circuit. Types of soft starters. DISCUSSION Introduction Direct-on-line starters Festo Didactic 88197-10 7
Exercise 1 DOL Starters and Soft Starters Discussion Motor protections Overcurrent protection 8 Festo Didactic 88197-10
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Exercise 1 DOL Starters and Soft Starters Discussion 10 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Motor start-up phenomena Start up current Festo Didactic 88197-10 11
Exercise 1 DOL Starters and Soft Starters Discussion Consequences of extended large currents 12 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Voltage sag Start-up torque Festo Didactic 88197-10 13
Exercise 1 DOL Starters and Soft Starters Discussion Soft starters 14 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Voltage output of a soft starter Festo Didactic 88197-10 15
Exercise 1 DOL Starters and Soft Starters Discussion Effect of the soft starter on the motor current 16 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Poly.(DOL) Poly.(SS) Effect of the soft starter on the motor torque Festo Didactic 88197-10 17
Exercise 1 DOL Starters and Soft Starters Discussion Effect of the soft starter on the motor speed 18 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Poly.(SpeedDOL (rev/min)) Poly.(SS) How a soft starter controls voltage Festo Didactic 88197-10 19
Exercise 1 DOL Starters and Soft Starters Discussion 20 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Discussion Bypass circuit Types of soft starters Festo Didactic 88197-10 21
Exercise 1 DOL Starters and Soft Starters Discussion 22 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure Outline PROCEDURE OUTLINE PROCEDURE Setup and connections In this part of the exercise, you will connect your equipment as a DOL starter, configure parameters in LVDAC-EMS so that the Four-Quadrant Dynamometer/Power Supply emulates a flywheel, and set the Oscilloscope to observe the motor start-up current, torque, and speed. Power Input Power Input Low Power Input Power Input Festo Didactic 88197-10 23
Exercise 1 DOL Starters and Soft Starters Procedure Operating ModeDynamometer Computer-Based InstrumentationThyristor Control OK Tools Friction Compensation Calibration OK OK OI I1 a Current input I4 of the Data Acquisition and Control Interface is used to monitor the motor current in order to protect the motor from overheating if excessive currents flow through the stator windings. The range of current to be used for current input I4 is 40 A. 24 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure I1 I1 Sync. Festo Didactic 88197-10 25
Exercise 1 DOL Starters and Soft Starters Procedure Digital Output 1DO1D + Remote Control Analog OutputsT n Analog Inputs/T /n Analog Outputs A Function Mechanical Load Load Type Flywheel Inertia Friction Torque Pulley Ratio a Note that the pulley ratio between the Four-Quadrant Power Supply/Dynamometer and the Four-Pole Squirrel Cage Induction Motor is 24:24. FunctionDirect On-Line Starter Motor Full Load Current [FLA] OverloadOn Overload Class 26 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure I1) Analog Input 7/T Analog Input 8/n Peak Detect Starting an induction motor using a DOL starter In this part of the exercise, you will start the motor using a DOL starter. You will record the motor current, torque, and speed at start-up and analyze the results. StatusStarted Start/Stop Single Refresh Start a The above manipulation must be performed rapidly to ensure that the Oscilloscope records the entire evolution of the various parameters during motor start-up. Stop a Since the Oscilloscope operates in peak detect mode and a slow time base is used, it displays the envelope of the motor current rather than its waveform. Status Stopped Start/Stop Festo Didactic 88197-10 27
Exercise 1 DOL Starters and Soft Starters Procedure 28 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure a The maximal current obtained in step 22 is a peak value. Convert this peak value to an rms value before making the comparison. Festo Didactic 88197-10 29
Exercise 1 DOL Starters and Soft Starters Procedure 30 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure Soft starter setup and settings In this section, you will modify the equipment connections so as to replace the DOL starter with a soft starter. I1 Festo Didactic 88197-10 31
Exercise 1 DOL Starters and Soft Starters Procedure I1 32 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure Sync. Digital Output 1 Remote Control T and n Analog Outputs Analog Inputs7/T8/n Digital Outputs Firing Control Inputs Range I1 FunctionSoft Starter ModeSoft Start Motor Full Load Current [FLA] Initial Torque Start Time Soft Starter Initial Torque Kick Start Time Soft Stop OverloadOn Overload Class Festo Didactic 88197-10 33
Exercise 1 DOL Starters and Soft Starters Procedure Starting an induction motor using a soft starter In this part of the exercise, you will start the motor, still coupled to the same mechanical load used earlier in the exercise, using a soft starter. You will record the motor current, torque, and speed at start-up and analyze the results. Single Refresh Start a The above manipulation must be performed rapidly to ensure the Oscilloscope records the entire evolution of the various parameters during motor start-up. Stop 34 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure Festo Didactic 88197-10 35
Exercise 1 DOL Starters and Soft Starters Procedure 36 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Procedure DOL starter versus soft starter In this part of the exercise, you will compare the results you obtained with the DOL starter and the soft starter (for the same mechanical load) and try to deduce what the advantages and limitations of each one are. Festo Didactic 88197-10 37
Exercise 1 DOL Starters and Soft Starters Conclusion Tools Reset to Default Friction Compensation Yes CONCLUSION REVIEW QUESTIONS 38 Festo Didactic 88197-10
Exercise 1 DOL Starters and Soft Starters Review Questions Festo Didactic 88197-10 39
Bibliography Foundations of Analog and Digital Electronic Circuits Industrial Power Engineering and Applications Handbook Practical Variable Speed Drives and Power Electronics The Induction Machine Handbook Power Electronics Handbook Electrical Machines, Drives and Power Systems Power Conversion and Control of Wind Energy Systems Festo Didactic 88197-10 93