The Parameter Identifying And Parameter Self-tuning For The AC Permanent Magnet Synchronous Servo System

The AC servo system due to its advantages of good stability,high-speed performance,high accuracy,and fast adjustment speed,is widely used in robots,automation equipment,electric vehicles,aerospace and other fields.During the operation of the AC servo system,its parameters will change with the change of the working conditions(such as magnetic saturation,temperature,etc.)of the motor.If the parameters of the controller cannot be adjusted in real time,the motor will have noise or even Overpressure or overcurrent.This paper mainly studies the FPGA-based all-digital servo drive control technology of permanent magnet synchronous motors,and through parameter identification algorithms,identify the relevant physical quantities during the operation of the system,and then through the self-tuning algorithm to adjust the controller parameters to ensure the operating state of the servo system stable.At first,based on the working principle of permanent magnet synchronous motor,this paper derives its mathematical model in different coordinate systems.Then,established the SIMULINK mathematical simulation model,and simulated the working principle of the permanent magnet synchronous motor servo system with variable parameters to verify the influence of the parameter changes on the system performance during the operation of the motor,to indicate the necessity for online parameter identification.Secondly,based on the Model Reference Adaptive(MRAS)method,an online identification algorithm for the permanent magnet flux of the rotor of the permanent magnet synchronous motor?the inductance and the rotational inertia is designed.The transfer function of each link of the AC servo system is analyzed,the control block diagram of the AC servo system is established,and the transfer function is simplified.Based on the simplified speed loop transfer function,the speed-loop controller is proposed according to the frequency domain index requirements of the system parameter auto-tuning algorithm.Then,based on the above research work,the entire PMSM AC servo system was designed.The design of the hardware circuit mainly includes FPGA control circuit,RS-485 communication circuit,AD conversion circuit,IPM drive circuit and current and voltage sampling circuit etc.Servo system control procedures mainly include AC servo system general procedures,parameter identification and parameter self-tuning procedures,etc.Finally,the prototype of the servo control system was completed,and a test platform was built to test the motor control performance,and the effectiveness of the parameter identification algorithm and the control parameter self-tuning algorithm was verified.The experimental results prove that the proposed scheme is feasible.The control performance of the AC permanent magnet servo system has been significantly improved.