一种DPWM过调制技术的实现及应用

Realization and Application of DPWM Overmodulation Technology

针对传统SVPWM存在的不足,在详细分析其原理的基础上,提出了一种将不连续脉宽调制DPWM与过调制技术结合的新技术,分别将SVPWM、DPWM全区域算法应用于异步电机调速系统中进行仿真比较,结果表明,采用DPWM全区域算法,在过调制区内不仅可以保持电机运行时各项指标满足要求,而且可以有效减少逆变器功率器件的开关损耗,提高直流侧电压利用率,降低逆变器三相输出相电压及异步电机定子侧三相电流谐波畸变率。

Aiming at the deficiency existed in traditional SVPWM,after analysing the traditional principle of SVPWM,a generalized idea of the discontinuous pulse width modulation(DPWM)combined with overmodulation technique was introduced.SVPWM and DPWM overmodulation methods were applied to asynchronism machine speed control system respectively.The simulation results show that in over-modulation region,using DPWM overmodulation algorithm can not only keep the indicators meet the requirements when motor running,but also can effectively reduce inverter switching losses of power devices,improve DC voltage utilization rate,reduce the harmonic distortion of inverter output three-phase voltage and asynchronous motor stator three-phase current.