Research On Techniques Of Bidirectional AC/DC Converter For Household Energy Router

With the development of new energy technologies,the Energy Internet has become a new generation of energy systems,which can well fit the need of distributed power generation and multi-directional energy flow.The bidirectional AC/DC converter is the core component of the energy router— the core hardware component of the energy internet,and it plays an important role in the system operation and the energy allocation.However,current research on the control of bidirectional AC/DC converters,the improvement of filtering performance and power quality are not comprehensive.This dissertation studies the architecture,functions,and energy management strategies of household energy routers,designs the hardware of the bidirectional AC/DC converter and conducts research on multi-modal control strategy.Besides,the active power decoupling technology of bidirectional AC/DC converters is also studied in this dissertation.Firstly,the function and circuit analysis of the bidirectional AC/DC converter are researched considering the application background of the household energy router.A kind of household energy router architecture is proposed,which is composed of a power network,a communication network,and a control network.The basic functions of the household energy router are clarified and a layered coordinated control strategy is proposed to achieve reasonable energy allocation and optimal scheduling.Besides,the characteristics and main functions of the bidirectional AC/DC converter are analyzed and the single-phase full-bridge topology is selected as the main topology,its working principle and modalities are analyzed.Secondly,this dissertation designs the circuit of the bidirectional AC/DC converter and build a 1k W hardware platform.According to the performance and index requirements,Si C MOSFETs are selected to build the power circuit;The AC inductance and DC capacitance are calculated and selected.The circuit design is carried out,including the driving circuit,feedback and control circuit and EMI filter.In addition,basic debugging is conducted on the hardware platform to test the function and performance of the bidirectional AC/DC converter.Then,the control system of the bidirectional AC/DC converter is designed and analyzed in this dissertation.The large and small signal model of the bidirectional AC/DC converter are build and dq decoupling control strategy of the current control loop is derived.The current loop compensator is proposed to decouple the reference-tracking function and disturbance-rejection function of the bidirectional AC/DC converter,as well as improving the disturbance-rejection ability and dynamic performance of the system.According to different working conditions of the household energy router,the multi-mode control scheme based on the current loop compensator is proposed to achieve different functions in the corresponding working modes.Finally,this dissertation studies the active power decoupling technology of bidirectional AC/DC converters.The power flow of the bidirectional AC/DC converter is analyzed.Various topological structures and control strategies of active power decoupling method are compare and this dissertation chooses the Buck type capacitor energy storage circuit.The working principle is analyzed and the key parameter calculation and design are conducted.The inductor current is chosen as the control target and the control system is designed.Finally,the simulation is conducted to verify the effectiveness of the power decoupling method.The research of this thesis is of great significance to the functions,high-performance control strategies and high power density realization of the bidirectional AC/DC converters in household energy routers.