The Research and Implementation of Control Unit of the Three-phase Power Converter
|School||Tianjin University of Technology|
|Course||Control Theory and Control Engineering|
|Keywords||Three-Phase Converter Space Vector Current Control Predictive Link|
Three-phase power converter is able to achieve two-way transmission of electrical energy, which has the characteristics of controllable of the network side power factor and low harmonic pollution. With the continuous development of the power electronics technology, Domestic and foreign scholars have made a lot of research on how to improve the dynamic performance and immunity of the converter, in order to meet the requirements of different application areas. Firstly, starting from the topology of the power converter, in order to improve its performance. Secondly, many advanced control method were proposed in the control strategy aspect, such as the sliding mode control, neural network control, and robust control, to further improve the performance of the converter.For three-phase voltage converter, although many control methods can meet the requirements of high power factor and low harmonic factor, the influence of control parameters could reduce the control effect. This paper start from the system’s real-time indicators according to the problems and defects of the current power converter control system, and reseach on the impact on the control parameter. In the same time, this paper proposes an efficient real-time optimization strategies to eliminate the parameters affect.This paper base on the inspection of literature, analyze the real-time of three-phase power converter control unit at first, calculate the execution time of three-phase inverter typical control algorithm by using the methods of worst-case execution time, which can as the real-time standard of system software designation. Secondly, this paper analysises the impact on the real-time delay of the control unit of sampling period and deadtime, which are the typical control parameters, base on the result of real-time analysis, including the network side voltage and current harmonics, sampling effects, dynamic switching frequency and DC voltage regulation, etc.In the same time, validate the conclusions by the system modeling and simulation through Matlab Simulink simulation tools. In order to eliminate the impact on real-time delay generated by the dead time by using the method of compensation, this paper proposes an efficient real-time optimization mainly based on two ways:the optimization of the control parameters and the optimization of voltage switching vector, and illustrate the advantages and shortcomings of different methods by theoretical analysis.The project plan to design a hardware system of three-phase power converter control unit, that base on the dual-controller, DSP and FPGA. The designation of the hardware including device selection, interface circuit, and signal conversion circuit, and the software mainly related to dual controller communication module structures, and implementation of the FPGA main function. Finally complete the building, and debugging of the control unit.