Analysis And Study Of Harmonic Suppression Of High-power Permanent Magnet Synchronous Motor

Due to the distortion of air-gap magnetic field and the nonlinear characteristics of inverter, the current of PMSM may contain a large number of high-order harmonic currents, resulting the current waveform distortion and motor electromagnetic torque ripple. Torque ripple has made the PMSM less suitable for adjustable-speed drive in a wide range and high performance position and speed applications. Analysis and suppression PMSM running harmonic, reducing the PMSM outputs harmonic electromagnetic torque has become the focus of present domestic and international research.In order to solve this problem, after detailed analysis and the derivation of systems theory, in this paper, a novel harmonic suppression was proposed.Based on analyzing the basic working principle of PMSM and establishment of PMSM mathematical model, this paper had analyzed detailly the generation which caused the PMSM running harmonic and deduced a mathematical harmonic model of PMSM. A novel harmonic suppression algorithm, in this paper, was proposed.Harmonic component in the motor phase current was extracted in real-time under harmonic dq synchronous rotating coordinate shaft.The closed-loop control of harmonic current was achieved by adding harmonic current loop.Harmonic voltage was obtained accuratly,and injected it into the three-phase control voltage of the speed control system PMSM. Motor current harmonics in the motor components were offseted. The motor current waveform was improved and the motor harmonic current and electromagnetic torque ripple was suppressed effectively.Under MATLAB/Simulink, this paper established simulation model structures on the base of the harmonic suppression algorithm and had some comparison of the results of simulation.And it proposed the design of the PMSM drive system which based on digital signal processor (DSP- TMS320F2812), completed the drive system controller hardware and software design and system debugging. By adding the harmonic harmonic part or not, the comparison of the results of simulation and experiment showed that the algorithm was effective to suppress harmonics and reduce the output torque ripple of the high-power PMSM system. This algorithm is more flexible and adaptable, without involving any additional hardware and off-line experimental measurement.The work of this paper laid the theoretical foundation for further improving the performance of PMSM, expanding the scope of application of permanent magnet synchronous motor.