Keywords: particle swarm optimisation, PSO, selective harmonic elimination, SHE, voltage source inverters, VSI, pulse width modulation, uniploar PWM, bipolar PWM
Particle swarm optimisation-based solutions for selective harmonic elimination in single-phase PWM inverters
This paper presents accurate particle swarm optimisation based-solutions for non-linear transcendental equations of selective harmonic elimination technique used in single-phase PWM inverters. The proposed method computes efficiently the required switching angles to eliminate low order harmonics up to the 15th from the inverter voltage waveform while maintaining the amplitude of the fundamental harmonic at the desired value. The proposed PSO-based method is studied and tested for two possible switching patterns: unipolar and bipolar PWM. In both patterns, the minimisation method of selected objective function and evaluation of the method are presented. The results prove that the proposed method converges to the solution after a few number of iterations compared with other algorithms such as genetic algorithms and ant colony. The main contribution of the paper lies in the application of PSO algorithm to eliminate any desired number of harmonics. Moreover, the method is also applicable to three-phase voltage source inverters.