FPGA-based PMSM Drive System Modeling And Realtime Simulation Technology

Permanent magnet synchronous motors are widely used in industrial and agricultural production,rail transit,electric vehicles and other fields because of their simple structure,small size,high efficiency,and strong overload capacity.In the previous process of research and development of the control strategy of permanent magnet synchronous motor drive system,although the experimental results are close to the actual working conditions,the development cycle is too long,the development cost is too high,and the repeatability of the experiment is also poor.Carelessness can easily cause damage to the experimental equipment and even casualties.In offline simulation,the actual controller cannot be adjusted in real time,and the offline simulation time is different from the real running time,and the real-time performance of the simulation is poor.The semi-physical real-time simulation system,especially the emergence of hardware-in-the-loop real-time simulation technology(hardware-in-the-loop,HIL)can effectively avoid the abovementioned problems encountered in the development of motor drive system control strategies.The hardware-in-the-loop simulation system uses a digital system to simulate the real hardware circuit model and is connected with the real control system to test the feasibility of the control system and the effectiveness of the control strategy.The emergence of this kind of simulation technology can significantly shorten the motor control strategy.The research and development cycle reduces the cost of research and development,and the repeatability of the experiment is high,and it can simulate the operating conditions of a variety of fault limit conditions.The main contents of this paper are as follows:(1)Modeling the various parts of the permanent magnet synchronous motor drive system.The inverter modeling method and the continuous mathematical model discretization method of the permanent magnet synchronous motor are analyzed,discussed and compared.Model the main circuit of the three-phase inverter with the switching function method,use Euler’s method to discretize the continuous mathematical model of the motor,And combine load and resolver models to realize the overall modeling of the system.(2)A method for generating real-time simulation models is introduced.With the help of the System Generator(SG)toolbox,the system’s real-time simulation model is built,and the Verilog project file is generated through the toolbox,so that the real-time simulation model can be run on the FPGA-based hardware-in-the-loop simulation platform.(3)Due to the limitations of the module for solving the sine and cosine values of the motor angle in the SG toolbox,its convergence angle is only valid in the interval [-π/2,π/2],so an improved CORDIC algorithm is used to build the system Real-time simulation model of the controlled object.(4)Based on LabVIEW software and Xilinx’s ZYNQ 7020 FPGA development board,a low-cost hardware-in-the-loop real-time simulation platform is designed through software programming,and a real controller is used to perform real-time simulation model of the permanent magnet synchronous motor drive system.VF control experiment,and id=0 vector control closed-loop experiment.Through comparison with Simulink simulation results,the feasibility and accuracy of the built-in hardware-in-the-loop realtime simulation system and the validity and correctness of the modeling of the permanent magnet synchronous motor drive system are verified.