| With the rapid development of China’s economy and the improvement of our material life quality,the ways of transportation are becoming more and more convenient and diversified.Among them,driving is an essential part of people’s life.However,as the main energy source of traditional fuel vehicles remains to be fossil fuel,fossil fuel crisis and environmental pollution caused by its extensive use restrict the further development of China’s social economy.With the upgrading of traditional fossil energy,the application of new energy is imperative,and the application of new energy electric vehicles is in line with the trend of the times.Among various kinds of new energy electric vehicles,blade electric vehicle is in the leading position because of its advantages of non-pollutant emission,low noise,simple structure,convenient maintenance and high energy utilization.Nowadays,single-phase pulse width modulation(PWM)rectifiers have been widely used in electric vehicle charging systems,due to their high efficiency,small size,low cost,and high reliability.Compared with the conventional diode or thyristor rectifiers,single-phase PWM rectifiers can achieve unity power factor,reduced current harmonics and bidirectional power flow.However,due to the harmonic components of the grid voltage,the prediction error of the control method and the ripple voltage pulsating of the DC voltage at twice the grid frequency,the performance of current control for the single-phase PWM rectifier at steady state is affected.Therefore,it is necessary to carry out the control method improvement and topology design of single-phase PWM rectifiers for EVs from these three aspects in order to improve the operation performance of the charging systems for EVs.Firstly,an improved deadbeat current predictive control method for single-phase PWM rectifiers is proposed,in which the AC side voltage compensation parameter h approaches to the optimal value by a given step size.Due to the design of the current loop,the influence of the harmonic components of grid voltage and the prediction error of the control method on the performance of the current control is reduced.As a result,the power factor of the rectifier is increased and the total harmonic distortion(THD)of the input current is reduced.The voltage loop uses an active disturbance rejection controller(ADRC),which improves the dynamic performance of the system.Secondly,after analyzing the stability of the proposed deadbeat current predictive control method with voltage compensation parameter h,a new deadbeat current predictive control method based on direct calculation of voltage compensation parameter is proposed to speed up the adjusting speed of the voltage compensation parameter and reduce the impact of adjusting h on DC output voltage.Thirdly,in order to solve the problem that the second-order voltage ripple of DC side of single-phase rectifiers affects the current control performance and reduces the lifetime of the power batteries in the electric vehicle charging system with single-phase power grid,a single-phase rectifier active power filter topology with output capacitors reverse series is proposed.Finally,the hardware experimental platforms are built in this paper,and the feasibility and effectiveness of the proposed control methods of single-phase rectifiers and the porposed active power filter topology are verified by experiments. |
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