Real-Time Simulation Research Andimplementation Of Motor System

At present,motors play an increasingly important role in many fields such as aerospace,industrial equipment,rail transit,home appliances,etc.Testing is an important part of the design process of the motor system,the choice of simulation means has a great influence on the motor system test.Simulation is a necessary test method for the motor system,the advantages and disadvantages of the simulation method greatly affect the confidence of the simulation.Realtime simulation is the most reliable method in the simulation method,therefore,the real-time simulation of the motor system naturally becomes the main research content of this thesis.In this thesis,the motor system is taken as the research object,and the real-time simulation of the motor system is the research content.Through the research on the real-time simulation technology and method of the motor system,the characteristics of the test object,test content and difficulty level of each real-time simulation method of the motor system are analyzed and summarized,it is concluded that the power-hardware-in-the-loop simulation of the motor system is the best real-time simulation method of the motor system.For the motor system power-hardware-in-the-loop simulation problem,the controller,driver and motor involve highfrequency signal processing,the motor load model contains ordinary differential equations involving a large number of floating-point operations,using the CPU+FPGA architecture,the motor model is placed on the FPGA and the load model is placed on the CPU,which comprehensively utilizes the powerful floating-point computing power of the CPU and the powerful high-frequency signal processing capability of the FPGA.In order to verify the rationality of CPU+FPGA simulation architecture,based on Modelica’s proposed model-split method,the rationality of model allocation under CPU+FPGA architecture was verified by offline co-simulation based on CPU.In order to realize real-time simulation of CPU+FPGA,the modeling and simulation of motor on FPGA is studied.Firstly,this thesis designs a motor system CPU+FPGA power-hardware-in-the-loop realtime simulation architecture for a typical motor system.According to the principle of Modelica modeling and the law of conservation of energy,this paper studies and proposes a reliable model-split method.Based on offline CPU co-simulation verify the rationality of the model allocation scheme for CPU+FPGA,and the reason and step selection basis of the electric system using small-step size simulation are given.Secondly,the existing complex motor system model is reasonably simplified,and the physical principle and mathematical principle equation of the key parts are given,such as motor,controller,etc.According to the model-split method,the model is split reasonable.Analysis of the FPGA implementation of the motor model,and complete the discrete solution deduction of the motor model.On this basis,a real-time simulation platform is built to select hardware,software and communication methods,and the real-time programming of the motor system is performed on the PC computer terminal,real-time CPU terminal and FPGA terminal of the platform.Finally,the real-time simulation experiment of the real-time simulation system of the built motor system is carried out.The offline simulation results are compared,and the time precision of real-time simulation is analyzed.The key factors affecting the real-time accuracy are given.