Study On The Algorithm Of Random SVPWM

Because of the loudly magnetic-acoustic noise caused by SVPWM that controls the power component on and off determinately, this thesis gives us a study about different Random SVPWM Techniques on the effect of reducing the magnetic-acoustic noise.The thesis introduces the research background and the importance of the random SVPWM, and then it presents the state of the art of the random SVPWM. Also it gives some introduce and analysis to the random pulse position SVPWM and random switching frequency SVPWM, which emphasize the analysis of the current ripple and current's HDF(Harmonic Distortion Factor) caused by different random pulse position SVPWM, corresponding to that we also gives quantitative design to the range of the random frequency of random switching frequency SVPWM. Based on the method of random number generator and the evaluation of the random ability, we give the simulation model and analysis and implement Random SVPWM in the power supply system on the locomotive successfully.The simulation and experiment results testify that the random switching frequency SVPWM distributes the higher harmonic which at the switching frequency and its multiple's to all over the spectrum, thus it can reduce the peak value of the harmonic at the switching frequency and its multiple's and realize the reduction of the harsh magnetic-acoustic noise on the locomotive.