Supercapacitor Balancing Circuit Design Considerations for High Current Charge-Discharge Cycles

This paper describes design considerations and verification for supercapacitor balancing circuit that works with charge-discharge cycles up to 50A for 48V DC microgrid. The paper analyses design of passive balancing circuit that is based on MOSFET array and works without outer control. Simulation in LTSpice software has been created and compared with theoretical analysis. Experimental prototype has been built and practical results are compared with theoretical ones. The circuit has been tested with multiple charge-discharge cycles at 30A over long period of time. The paper discusses circuit parameter calculation, circuit simulation results, experimental balancing circuit testing and parameter verification.