Patent ID: 7420824
Filing Date: 2008-09-02
Classification: H02M

Abstract:
1. A method of designing a random pulse width modulation (RPWM) inverter with unwanted harmonic elimination, where the RPWM inverter has an RPWM waveform with M (a positive integer) trigger angles (α 1 , α 2 , . . . , α M ) and the M trigger angles respectively indicate start and termination angles of the RPWM waveform, the method comprising the steps: (A) selecting an amplitude modulation index M (B) computing start values for the M trigger angles based on an equal area approach; (C) selecting both low-order harmonics to be eliminated and randomly produced harmonics and producing M non-linear equations; (D) transforming the M non-linear equations into M linear equations; and (E) using a numerical iteration to compute the M trigger angles based on the start values.