Communication Torque Ripple Reduction Research Of The Modified Z-source Inevrter Fed BLDCM

Permanent magnet brushless dc motor(PMBLDCM)is developed on the basis of the DC motor,it has a simple structure,large output torque,high efficiency and fast response,etc.It not only keep the DC motor speed control performance is good wait for a characteristic,at the same time using electronic commutation to replace the mechanical commutation,solved a series of problems caused by commutation.Therefore,in recent years,PMBLDCM is widely used in office automation,aerospace,electric cars,in the field of industrial process control,etc.However,due to its own structure,it has the problem of torque ripple.When it is used in some high-precision servo system,the demand for torque ripple is more stringent,and how to restrain torque ripple is also an important basis for measuring the performance of brushless dc motor.Firstly,this paper expounds the basic structure of PMBLDCM and the basic working principle,deduces the mathematical model of PMBLDCM,describing the commutation in PMBLDCM transient process;Introduced the brushless dc motor and the cogging torque,non-ideal back emf waveform caused by the torque and commutation torque caused by the torque ripple;Introduced the torque ripple of PMBLDCM driven by slot effect,non-ideal anti-electromotive force waveform and current commutation.Because of the PMBLDCM torque ripple mainly comes from the commutation torque ripple,the additional circuit of the z-source inverter is introduced,and the method of solving the torque pulsation is emphatically analyzed.and aiming at the existing defects of traditional Z source inverter topology,its structure and control method were improved,and the modified Z source inverter is designed.Secondly,in order to verify the effect of the inhibition of the torque ripple,in this paper,the application of Matlab/simulink simulation software,respectively to the Z source inverter and the modified Z source inverter for PMBLDCM drive circuit to simulate experiment.Simulation results show that the modified Z source inverter contrast Z source inverter commutation torque ripple suppression of better,Moreover,there are no such shortcomings as the starting current of Z source inverter and the interruption of input current.Finally,set the TMS320F2812 as the control chip of the permanent magnet brushless dc motor control circuit,at the same time,detailed introduces the design scheme of hardware and software of the control system and build the system experiment platform.The software of CCS3.3 is used to debug and develop the environment,and measure the phase current waveform and torque ripple waveform at different speeds.The experimental results are consistent with the simulation results,and prove that the method proposed in this paper can reliably and effectively inhibit the torque ripple of brushless dc motors.