Contents. Electric Double Layer Capacitors

Transcription

1 Electric Double Layer Capacitors A battery is a device which can temporarily store and discharge electric energy. The Electric Double Layer Capacitor (EDLC) can replace or supplement batteries due to its outstanding properties, such as low internal resistance & long life. The following introduces application examples, features & benefits of ELNA's ELDC products: DYNACAP Contents Uses of an Electric Double Layer Capacitor Typical application chart for Electric Double Layer Capacitor Key features and benefits of an Electric Double Layer Capacitor 1. Equalization of input electric power Equalization of output electric power Regeneration of the wasted electric power A reliable power supply in emergency Discharge time required is pre-set

2 Contents Applications of EDLC and the Range of Characteristics Discharge time (sec) Small cap. Med. cap. Large cap. MEMORY BACKUP 3 to 5V TOYS 2 to 3V PROJECTOR COOL FAN 12V TRAFIC REFLECTOR 2 to 5V Actuator 5 to 24V LED LIGHTING 3 to 12V ENERGY RESURRECTION Energy regeneratio 50 to 400V of Train 500 to 1500V COPY MACHINE DRUM MOMENTARY HEATING SMALL WIND POWER MEMORY WRITER DISPERSION POWER 50V GENERATION BUFFER 1 GENERATION BACK UP 5 to 12V 200 to 400V 50 to 100V Instant Brake UPS BATTERY ASSISTANCE SMALL FUEL CELL ASSISTANCE 100 to 600V to 12V 3 to 5V Capacitance (F) V F 5.5V 1F 12V 2F 15V 8F 2.5V 450F 2.5V 2.2F 2.5V 10F 2.5V 100F

3 Features & Benefits of Electric Double Layer Capacitor (compared to battery) Low resistance 1 USB bus power assistance Battery load reduction Copying machine drum pre-heat 2 Windmill power variance 3 Elevator Railroad vehicles Heavy Duty / Construction Equipment UPS 4 Emergency actuator drive Emergency memory drive Long life LED drive Memory backup Electric toy 5 PC Projector cooling fan Linear charge & discharge property Equalization of input electric power. Benefit: It charges slowly and discharges quickly Equalization of output electric power. Benefit: It charges quickly and discharges slowly (uniformly Regeneration of wasted electric power. Benefit: It charges quickly and discharges quickly A reliable power supply for emergencies. Benefit: It is maintenance-free and highly reliable Discharge time required is pre-set. Benefit: User interaction is not required.

4 It charges slowly and discharges quickly. 1. Equalization of input electric power. In order to supply a momentary large discharge of power, the Electric Double Layer Capacitor (EDLC) is added to the maximum power supply output (Note: if high power is not needed, a large power supply output will worsen total efficiency). Rapid charge & discharge of the EDLC is possible and with little charge discharge degradation, the EDLC is the the best solution. Conceptual diagram Without EDLC Power supply Load The example of a load current wave Equivalent With EDLC EDLC charge addition Since the peak current drops, the power supply can be reduced Power supply Load The example of power supply current wave type Discharge current EDLC Charge current Example of EDLC current wave Application Examples: Battery load reduction (DSC, transmitter dispatch assistance, HD audio etc.) Electric toy USB bus power assistance Copy machine drum pre-heating

5 Example of stabilizing load change Voltage decency control of battery makes it usable as long as possible BATTERY LOAD ASSISTANCE SIMULATION Use at DSC BATTERY EDLC LOAD 460mA 460mA 230mA 230mA DLC 0.7F low ESR 400ms 200ms 400ms 200ms ELECTRIC LOAD DEVICE INPUT WAVE FORMCYCLE EDLC in parallel connection with battery can stabilize the battery load charge. With EDLC allows battery to have longer life and to be smaller in size. DLC can be used with Fuel cell batteries, Lithium batteries, Manganese batteries

6 It charges quickly and discharges slowly (uniformly). 2. Equalization of output electric power. An Electric Double Layer Capacitor (EDLC) has extraordinarily higher capacitance compared to a common capacitor also to float charge and fault electric discharge from a battery, it is the the best for absorption of change and equalization of the big electric power in a big span. Conceptual diagram Without EDLC Loss Electric power generation source Converter Example of input wave The fixed output is not obtained Example of output wave With EDLC Discharge current Electric power generation source Converter Charge current EDLC current wave type EDLC Example of output wave Application Example: Wind power change absorption

7 It charges quickly and discharges quickly. 3. Regeneration of wasted electric power. In an application in which a round trip, up-and-down motion, or start-stop is repeated, the energy generated at the time of the opposite direction of work is typically wasted. If the energy can be recovered, it is possible to use that energy as a supplement power source for the forward direction operation. In order to recover efficiently, the Electric Double Layer Capacitor (EDLC), which can be rapidly charged & discharged due to it's low internal resistance. Conceptual diagram Without energy regeneration Power supply Load Unrecovered, the energy potential is lost With energy regeneration Energy cannot be recovered and is Current wave form example Efficiency goes up Power supply Load Charge (regeneration) current Current wave form example EDLC Regeneration Discharge current Charge (regeneration) current EDLC current wave type Application Examples: Elevator Heavy Duty Construction & Farm Equipmen Railroad Vehicles

8 It is maintenance-free and highly reliable. 4. A reliable power supply for emergencies. Generally, an Electric Double Layer Capacitor (EDLC) has the following advantages as compared to a battery (in addition to low internal resistance): a. Unlimited charge and discharge cycles. b. Wide operating temperature range. c. Low capacitance loss over life of product. d. Even with a decline in capacitance, the EDLC will be usable to max voltage. An EDLC is ideal as a source of backup power with long-term reliability. Application Examples: Uninterruptable Power Supply (UPS) Emergency actuator drive (power failure) Circuit operation in case of power failure (IC, a memory card drive, HD drive, etc.) LED drive (Combination with a solar battery) Memory backup of real-time clock (RTC) etc. User interaction is not required. 5. Discharge time required is pre-set. If voltage output declines, in a linear method, an Electric Double Layer Capacitor (EDLC) can be used to set the operational time by choosing a specific capacitance value. Essentially the EDLC becomes a power supply, without the need for a switch. Discharge time, voltage, and capacitance is shown in the following formulas: For constant current discharge: t :Discharge time t = C X ( V 0 - V 1 ) / I C :Capacitance I :Discharge current For constant resistance R :Load resistance (load) discharge: V 0 :Charge voltage t = - C X R X ln ( V 1 / V 0 ) V 1 :After discharge voltage Application Examples: Electric toy PC Projector cooling fan