Real-time power system control of model electric vehicles with supercapacitor as an ancillary device

Another method for the hybrid system is supercapacitor in series connection with the battery. At first glance, this does not seem to be conventional for electric vehicles since the system voltage starts at a higher value (from the SC) and decreases until 0 V due to the supercapacitor. Because of this, there has been virtually no extensive research into this method. However, using the series connection gives several advantages over the parallel circuit.

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1. There is no need to balance the voltage between the battery and the supercapacitor.

2. Supercapacitor’s entire voltage range can be used to power the vehicle.

3. Regenerative braking configuration is simpler, thus it is lower in cost.

 

By using a diode and a switch, it is possible to control the voltage of the vehicle using a PWM DC/DC converter. As a supercapacitor starts at a certain voltage, the battery voltage is reduced to allow for constant overall voltage feed to the motor. The biggest advantage of this system is that the supercapacitor’s voltage can start at a value much lower than that of the battery pack. Supercapacitor gets extremely heavy as the voltage gets higher, which is the biggest reason for commercial electric vehicles to avert supercapacitors in the vehicle power system.