A Random PWM Scheme Based on Coalescing the Pseudorandom Triangular Carrier and the Randomized Pulse Position for Voltage Source Inverters

A novel hybrid pseudo randomized triangular carrier and randomized pulse position scheme for voltage source inverter is proposed in this paper in order to disperse the acoustic switching noise spectra of an induction motor drive. The proposed random pulse width modulation (RPWM) pulses are produced through the logical comparison of a pseudorandom binary sequence (PRBS) bits with two random triangular carriers. Here, the PWM pulses of the proposed scheme possess the hybrid characteristic of the random pulse position PWM and the random carrier frequency PWM. The proposed technique is evaluated using MATLAB/Simulink and the results prove an excellent harmonic spectra spreading capability of the proposed hybrid scheme as compared with conventional schemes.