Research On The Key Technology Of Super Capacitor Energy Storage System Connecting To The Grid

Super Capacitor energy storage technology is to store energy by transforming electric energy to magnetic energy.It has got attention of a lot of researchers in the world because of its advantages of high efficiency,long service life,no pollution,rapid response,high power density,and high energy density,and this magnetic energy storage technology has extensive application prospects.As for now,it has been used in various fields such as electric vehicle,aviation,military industry,and renewable energy technology.In this paper the Super Capacitor’s operational principle and physical model was introduced in detail,a bidirectional DC-DC circuit was also designed and its working process was analyzed in detail.Then a Super Capacitor energy control system was built to realize the target of charging with constant current and discharging with constant voltage.For the reason to realize the lower steady-state error and reduce the affection of dynamic performance of the system caused by the linear algorithm using in the nonlinear system since the charging and discharging process of Super Capacitor is a nonlinear system and the PI control method is a linear algorithm,a nonlinear control algorithm was designed according to the nonlinear characteristic of the Super Capacitor energy storage system.Simulation model was constructed in MATLAB/Simulink platform and through it the bidirectional circuit and control algorithm were proved then.Considering the working process of the Super Capacitor,the control system was divided into control system and interactive system respectively,and two series DSP was used.TMS320F2812 which was produced by TI company was used in the interactive system while TMS320F28335 which having better performance and faster operating speed was used in the control system.Then the hardware platform was constructed in the laboratory by programming and hardware circuit designing.At the end of this paper,the performance of nonlinear control algorithm and PI control algorithm was compared by experiment and the effectiveness of the hardware circuit design was also verified,which is laying a good foundation for further research.