Research On Passivity-based Control Method For Permanent Magnet Synchronous Motor

The permanent-magnet synchronous motor(PMSM)has higher torque/inertia ratio and power density than an induction motor or a wound rotor synchronous motor.This makes it suitable for some applications likes robotics and aerospace actuators.However,it is difficult to control because of its nonlinear dynamical behavior and its time-varying parameters.The traditional PID control is difficult to get the satisfactory performance of the system,so it is necessary to introduce some advanced control strategies to realize high speed control performance of the PMSM system.The passivity-based control is a essentially nonlinear control method based on stability theory,its controller is easy to design and adjust,the control method has no singularity problem and has received widespread attention form many scholars and experts.Some research on the passivity-based control(PBC)method of PMSM speed control system have been done in this paper,concrete contents and conclusions are as follows.The research background and significance of this paper have been discussed firstly.The main control methods and strategies which are applied in the field of servo control at home and abroad have been introduced.Then the development and application of the passivity-based control method have been recommended,and its shortcomings are presented.Secondly,this paper introduces the basic structure and mathematical model of the permanent magnet synchronous motor.The system simulation model is built according to the basic principle of the vector control system,and the simulation is carried out to prove the correctness of model.These research lay the foundation for subsequent algorithms and simulation.Thirdly,the Euler-Lagrangian(EL)model of PMSM is studied in this paper.And the passivity-based current controller is designed by energy forming and damping injection.The simulation results show that the controller has better control performance than traditional PI control.Then,an exactly robust passivity-based control strategy based on the compensation of observer is proposed to solve the parameter perturbation and the approximately decoupling problem of the passivity-based controller.The observer is designed to observer the perturbation caused by uncertain parameters and the error caused by incomplete decoupling,and compensate to the controller output to improve the robustness of the system.Fourthly,the Port-controlled Hamiltonian system with dissipation(PCHD)system model of PMSM is studied in this paper.And the conventional passivity-based controller is designed by using interconnection and damping assignment method.Then,a novel passivity-based speed controller based on PCHD model of error system is designed based on the idea of interconnection and damping assignment control.And the Lyapunov function is defined to prove that the expected error system has exponential convergence.Finally,this paper introduces the design method of the integral action passivity-based current controller based on the extended PCHD model.The passivity-based controller is designed by energy shape and damping assignment method.Then the integral action is introduced to the controller to suppress the load disturbance and the disturbance in the actual dynamic model of the motor.The introduction of integral action is achieved by expanding a new state variables into the system PCHD model.The new state variables are the integral of system outputs.