Energy Distribution And Control Of Bidirectional DC Converter With VSG

With the gradual consumption of petroleum,petrochemical and other traditional non-renewable energy sources and their negative impact on the environment increasing year by year,distributed clean energy sources such as wind and light power generation have developed rapidly in recent years.Micro-grid system and distributed power generation technology have become the research hotspot in recent years.It is important for that research of direct current converter and control strategy in the micronetwork system to make the power of distribute power to be a good grid system in the microscreen system.In this paper,the effects of the alternating side of the dc,the control method and energy distribution strategies of the dc lateral converter,to improve the dynamic performance of the dc lateral system in the work of a micro-net inverter using the VSG control strategy.First,on the dc side of the micro-network inverter using VSG control strategy,the buck-boost semi-bridge circuit was selected as the topology of the dc converter,and the overall topology of the system was introduced and analyzed theoretically.According to the performance index of the converter,parameter design and power element selection are carried out for the bi-directional dc converter.Adopted by the second,on the net inverter VSG control strategies are introduced,and analyzed the control strategy of the key parameters on the dc side VSG configuration the influence of power and energy storage capacity;A small signal model has been set up with a DC/DC/DC converter,and it has designed a single loop controller and a drooping two-loop controller for the main circuit;It analyze that parameters of the dc bus by changing the parameters of the controller to change the bandwidth of the dc converter system,and simulates the parameters of the dc bus voltage current when the system is at different bandwidths,and is simulated in Matlab.Then,the energy distribution strategy of supercapacitor and battery hybrid storage is studied.After analyzing the traditional low-pass filter type high frequency power allocation strategy,and then to the super capacitor is introduced into power compensation link,to the accumulator is introduced into power limiting link,to improve energy distribution strategy,and simulation in the Matlab simulation environment.Finally,we set up a hardware experiment platform,including the main powercircuit,the isolation circuit,the sampling circuit,and the drive circuit.The theory proposed in this paper is validated.