The Research And Design Of A PMSM Decoupling Control Synthesis

PMSM has many advantages:strong air flux density, small size, high power factor and large starting torque, has been used in high acceleration, high-speed, high-precision drive control widely. As the rapidly development of rare-earth permanent magnetic material, power electronics and micro process, manufacturing techniques, the control system of PMSM becoming a new development and hotpot in all electric drives. Therefore, there is practical purpose to research the control system of PMSM. This thesis studied the decoupling algorithms of PMSM both in theory and simulation, provide theoretical foundation for application.Vector control makes PMSM stator current excitation component and torque component decouple, but it decouple a static variation, will not decouple the dynamic coupling relationship. This thesis developed the coupled mathematical model of Permanent Magnet Synchronous Machine (PMSM) based on d-q axis after the Park and Clarke transformation, this model can be equivalent to DC motor in dq axis. In this case, the principle of three decoupling techniques are presented and applied to PMSM, including compensation method, matrix transfer diagonalization technique and state feedback decoupling technique. The simulation results indicate the techniques solve the coupling problem, the effectiveness is verified statically and dynamically, this technique is superior in feasibility.Using the Matlab/Simulink simulation software, both simulation and control models of DSPMSG-AC-DC Converter-capacitor-load set are developed, and the decoupling algorithms are investigated. Including the simulation of generator, the design of voltage and PI current regulator controller, the implement of PWM converter, the design of decoupling block and the set of load.The decoupling ability on DSPMSG-AC-DC Converter-capacitor-load set system is investigated statically and dynamically through the test date. The results of the simulation indicated the validity of compensation decoupling method in PMSM, but limited to the single-phase synchronous motor. Matrix diagonalization method can be applied to multi-phase permanent magnet synchronous motor, but it requires an inversion of high order matrix of system which is difficult to achieve in project. State feedback decoupling technique effectively solve nonlinear, strong coupling problem of induction motor. Transfer the fourth-orders permanent magnet synchronous motor to a one order decoupled system. State feedback decoupling technique without the constrain of singular object coupling matrix, have wider range of applications than the matrix transfer diagonalization technique, can set pole position arbitrarily and establish the system model with different response time constant, has the advantage of high flexibility. Simulation results show the DSSG without the estimation of parameters, the decoupling effectiveness in permanent magnet synchronous generator with state feedback decoupling technique and matrix transfer diagonalizaton technique are equivalent; with the estimation of induction and resistance in permanent magnet synchronous generator, the state feedback decoupling is superior to matrix transfer diagonalization in respect to the sensitivity and anti-interference. The state feedback decoupling the voltage and current, have better dynamic and static ability and feasibility. Furthermore, the simulation has indicates the permanent magnet synchronous generator AC-DC Converter capacitor-load set system is feasible in project.