Research On Common-Mode Voltage Suppression Strategy Of Permanent Magnet Synchronous Motor

The acceleration of the modernization process has promoted the rapid development of power electronics technology,and the performance of the permanent magnet synchronous motor(PMSM)inverter drive system has also received extensive attention.Space Vector Pulse Width Modulation(SVPWM)plays an important role in the permanent magnet synchronous motor inverter drive system.When SVPWM modulation is used in the PMSM vector control system,the PMSM drive system will output a high-amplitude and high-frequency common-mode voltage,which will damage the motor bearings,generate electromagnetic interference,and affect the normal use of surrounding device.Therefore,it is necessary to study common-mode voltage suppression technologyAnalyzing the characteristics of the output common-mode voltage of the PMSM inverter drive system under SVPWM modulation,it is found that the amplitude and frequency of the inverter’s output common-mode voltage are higher under the action of zero vector.Therefore,this article analyzes the use of NSPWM,AZSPWM1,AZSPWM2 and AZSPWM3 non-zero vector modulation methods to suppress common-mode voltage.The characteristics and applicable modulation ranges of four non-zero vector modulation methods are studied.Two modulation methods,NSPWM and AZSPWM3,are selected for hybrid modulation,which realizes a high-performance common-mode voltage suppression strategy under wide modulation range and full power factor.The simulation verification based on MATLAB/SIMULINK has confirmed the effect of the hybrid modulation strategy in suppressing the common-mode voltage in the PMSM vector control system.In addition,when the PI controller is used in the current loop of the PMSM vector control system under hybrid modulation,the design of the PI adjustment coefficient is complicated,and the precision of the PI parameters is high,which is often difficult to meet the high-performance control requirements.However,the use of MPCC does not require parameter tuning and has a fast dynamic response.Aiming at the problem of large direct-axis and quadrature-axis current ripples in the traditional single-vector MPCC common-mode voltage suppression strategy,a three-vector MPCC common-mode voltage suppression strategy based on hybrid modulation is proposed,which effectively suppresses the common-mode voltage and reduces the current ripple of direct-axis and quadrature-axis.The simulation model is established based on MATLAB/SIMULINK,and the effectiveness of the algorithm is verified.Finally,in order to further verify the effectiveness of the strategy,a experiment platform with TMS320F28335 DSP as the control chip is built.At the same time,the host computer is established based on Lab VIEW virtual instrument program,and the experimental results are analyzed to verify the effectiveness of the above algorithm.