Research On Constant Power Charging And Discharging Control System Based On Supercapacitor

With the social economy high speed development, the energy crisis is approaching, so exploring the new energy and researching the new energy storage technology is increasingly urgent. At present, exploring the new energy sources has achieved initial results, such as wind power, nuclear power, photovoltaic power generation, but there are problems when it comes to the new energy efficient utilization and interconnection. Compared with the traditional energy storage carrier, Super capacitor has more significant advantages in cycle life, charge and discharge efficiency and other aspects, but how to further to improve the performance of supercapacitors is becoming a hot spot. Based on this the paper has carried on the research of supercapacitors constant power charging and discharging control system (CPCS).Firstly, it designs the system structure with two tube forward convertor, and analyzes working principle of the CPCS. For the characteristics of the convertor in the mode of charging and discharging, we simplify the equivalent circuit. And then, with the working time sequence of switching tube, we analyze the equivalent circuit at different mode in detail, which provide the theoretical basis for establishling the average switch model of the CPCS.Secondly, in combination with CPM strategy of the main topology circuit we analyze its stability. When D> 50%, we put forward the slope compensation control strategy and models and analyze the test system after compensating. At last, we simulate the whole system in the Matlab/Simulink. Compared with simulation waveform without slope compensation, the system has a good improvement in startup characteristic and disturbance characteristic after compensation, and achieves the expected target.Fanally, we set up the system experimental platform. For the hardware, we design the main circuit, the IGBT drive circuit, the slope compensation circuit, etc. For the software, we design the main program, the ADC sampling subroutine program, the choice of work mode subroutine program, etc. At last, we draw a conclusion that the system has reached the control target on constant power charge and discharge.