A new optimization method is proposed in this paper for finding the firing angles in multi-level voltage source inverters to eliminate low-order selective harmonics and reduce total harmonic distortion (THD) value of the output voltage. For thid end, Fourier series is used for calculating objective function and selecting specific harmonics. Regarding the nature and complexity of the employed no...

The analysis and design of the phase-locked loop (PLL) system is presented for the phase tracking system of the single phase utility interface inverters Phase-locked loops (PLL) are widely used in power electronics equipment connected to the mains. The use of a square wave voltage-controlled oscillator instead of a sinusoidal one eliminates one multiplier, resulting in a simple PLL algorithm, s...

A single-phase shunt active power filter is used mainly for the elimination of harmonics in single-phase AC networks. In this paper a single-phase shunt active power filter based on, an indirect control technique is designed and simulated. This control technique is achieved by phase shifting the input signal(voltage/current) by π/2.The overall action of the shunt active power filter to eliminat...

Multilevel inverters supplied from equal and constant dc sources almost don’t exist in practical applications. The variation of the dc sources affects the values of the switching angles required for each specific harmonic profile, as well as increases the difficulty of the harmonic elimination’s equations. This paper presents an extremely fast optimal solution of harmonic elimination of multile...

Dead-time is necessary to prevent the short circuit of the power supply in PWM Inverters or converters. But, it will result in output voltage deviations and in case of lower values of current, lower order harmonics will be taken into account. So, dead-time elimination is required in all PWM Inverters or converters. This paper is dealing with a summary of dead-time effects in PWM inverters and v...

PWM inverters ideally shift the output voltage spectrum around the switching frequency. Thus ideally PWM inverters do not introduce any significant lower order harmonics. However, in real systems, due to deadtime effect, device drops and other non-idealities lower order harmonics are present. In order to attenuate these lower order harmonics and hence to improve the quality of output current, t...

The uncontrolled three-phase bridge rectifier has the least line current distortion among six-pulse rectifiers; however, its total harmonic distortion (THD) of 31.08% is unacceptable as per the contemporary power quality standards. This paper seeks to address the issue by elimination of triplen harmonics in the line currents by providing a deltawye transformer at the ac interface i.e. between t...