关键词: 高速永磁同步电机, 不连续脉宽调制, 开关损耗, 统一化实现

Abstract: In the case of high-speed permanent magnet synchronous motor drive, the switching loss of the inverter is one of the main factors affecting the driving efficiency of the motor system. Compared to traditional seven segment SVPWM modulation, discontinuous pulse width modulation ( DPWM ) can greatly reduce switch losses and improve system efficiency. There were currently six types of DPWM modulation strategies studied, and the performance of reducing
switching losses and output harmonics varied among different modulation strategies. To achieve optimal overall system performance, segmented composite modulation or target optimized modulation were often used. A new unified implementation method for discontinuous pulse width modulation based on DSP was proposed. The relationship between the zero vector distribution coefficient and three-phase instruction voltage under different modulation methods were analzed. To address the problem that the zero vector distribution coefficient was not a fixed value under the second and third types of discontinuous pulse width modulation, a reference instruction voltage was introduced. And based on the sum of the maximum and minimum values in the reference instruction voltage, the distribution coefficient value was determined. The unified implementation of SVPWM and six types of DPWM was completed, and different modulation methods could be quickly switched. The implementation method was convenient and reliable, and the effectiveness of the method was verified
by simulation and experimental results.

Key words: high-speed permanent magnet synchronous motor, discontinuous pulse width modulation ( DPWM ), switching loss, unified implementation