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Study on the effect of random spread spectrum on the vibration noise of underwater propulsion motor

This paper takes the deep-sea underwater propulsion motor as the research background and the permanent magnet synchronous motor(PMSM) as the research object. To meet the performance requirements of high control accuracy and low noise of underwater propulsion motors, this paper studies the harmonic voltage peak generated by Space Vector PWM(SVPWM) modulation. The suppression mechanism of harmonic peak distribution and random spread spectrum modulation strategy is analyzed. Based on random spread spectrum modulation, the double random spread spectrum algorithm with a better spread spectrum effect is studied. Finally, an improved scheme based on double random spreading algorithm is proposed. The simulation results show that the improved double random spread spectrum algorithm outperforms the traditional double random spread spectrum algorithm