Research On Control Strategy Of Super Capacitor Charging Converter On Energy Storage Tramcar

In recent years,the tramcar with super capacitor has gradually become a new trend of urban traffic because the traditional control mode is easily affected by the bad impact of the arch and rail contact which is caused a lot of problems.Therefore,how to improve the charging control performance of ultracapacitor has become a research hotspot.This paper based on the phenomenon that the charging current when the trackless trolley car is charged with the process of tramcar charging.The problems and shortcomings of the traditional PI control in the face of the above interference are analyzed.The new control strategy of nonlinear tracking differentiator with PI parameter tuning is theoretically analyzed and studied.The simulation results show that the new control strategy has strong anti-interference ability and more stable control when the disturbance was caused by bad contact between the bow and rail.Firstly,the background and significance of the paper are introduced,and the application of super capacitor and the control strategy of charging are expounded.The research status of charge control is analyzed.The main circuit model of PI double closed loop control system and the working principle of PI controller are described.The structure and characteristics of the traditional PI control double closed loop are analyzed and the charging simulation of the control method is carried out.In the case of the given charging target and the reference current,the change of the system load which is caused by the bad contact of the arch rail is added.The experimental results show that the traditional PI double closed loop control of the super capacitor charging process is greatly disturbed by the bad bow rail contact which is resulting in the system load mutation.Secondly,a new charge control strategy is proposed which adopts the PI parameter tuning of the outer loop voltage loop and the double closed loop control strategy of the inner loop current loop nonlinear differential tracker.After adding PI parameters to the outer ring,the PI parameters of the system are more accurate which is conducive to the stability of the control system.The inner loop current loop using nonlinear tracking differentiator can increase the disturbance rejection ability of the system by differentiating and tracking input and feedback.At the same time,the charging simulation model of nonlinear control strategy is established and the disturbance caused by load variation is added to the simulation then the simulation is carried out.It is verified that the new control method improves the control response speed,reduces the load changes caused by the bad arch rail contact,and the system has more adaptive ability.Finally,the article carried out the charging experiments of two control algorithms under different practical conditions by building a super capacitor charging platform.Though comparing the results of the two control strategies,the effectiveness of the proposed control method is verified.