Assorted carrier‐variable frequency‐random PWM scheme for voltage source inverter

Abstract

This study presents an assorted carrier-variable frequency random pulse width modulation (AC-VF-RPWM) method in which a new type of mixed carrier wave is proposed for a three-phase voltage source inverter-fed induction motor drive. This study has focused on the reduction of acoustic noise where a deterministic PWM strategy is replaced with a proposed RPWM. Inverted sine carrier, sine carrier and triangle carrier are used to compare with the reference sinusoidal wave to generate the pulse (lead and lag) positions. The two groups (lead and lag) each with three pulse positions are randomly selected and it aims at dispersing the harmonic voltage over a wide band area. The linear feedback shift register-based random bit generation algorithms are used to select the three pulse positions from the lead and lag groups. In addition, a frequency modulator converts the carriers into a randomised frequency, which will give more potency to the randomisation process. The results of cosimulation and experimental evaluation that the proposed method could provide harmonic power spectra of the voltage and current spreading over a much broader band area, as compared with the conventional schemes. In addition, Xilinx XC3S500E FPGA device synthesis results are presented.

Electromagnetic Vibration and Noise Suppression of Induction Motor Based on RPWM Selective Spectrum Shaping

“…The electromagnetic vibration and noise in AC motors near the switching frequency and its integer multiple can be effectively reduced by the RPWM strategy [4]- [6] and the size of the filter at the output of port the inverter can be reduced [7]. According to the different ways of randomness, the RPWM can be divided into random switching frequency pulse width modulation (PWM) [8], random pulse position PWM [9], [10] and random switching PWM [11], etc. However, the specific frequency harmonics cannot be selectively…”

“…The associate editor coordinating the review of this manuscript and approving it for publication was Firuz Zare. eliminated in traditional RPWM [12], [9], such as the specific frequencies which are harmful to the motor [13]. Low-order harmonics can be eliminated by calculating the switching angle with the selective harmonic elimination pulse width modulation (SHEPWM) strategy, such as the harmonic of 5th, 7th, etc.…”

Suppression of common‐mode voltage spectral peaks by using rotation reverse carriers in sinusoidal pulse width modulation three‐phase inverters with CFM

“…The CFM technology essentially expands the energy of spectral peaks to the adjacent frequency bands, which forms the effect of peaks shaving and valleys filling and achieves the result of suppressing the spectral peaks. The CFM includes periodic CFM [15][16][17], random CFM [18][19][20], and chaotic CFM [21][22][23]. Among them, the first two are used more.…”

A Novel RPWN Selective Harmonic Elimination Method for Single-Phase Inverter

“…As shown in Figure 1, RPWM can mainly be classified as 1) random switching frequency pulse width modulation (PWM) [2], 2) random pulse position PWM, 3) random switching PWM [3], 4) or hybrid random PWM [4]. According to the randomness of the pulse position, it can be divided into random lead-lag [5], random zero vector [6], random pulse center displacement [7], random pulse position [8], random phase-shifted PWM [9], variable delay random PWM [10], asymmetric carrier random PWM [11], single random pulse position [12], and fractal space vector modulation [13]. However, the traditional RPWM cannot suppress specific harmonics selectively, such as the resonance frequency of motors and other loads.…”