selective harmonic elimination (she) is a powerful modulation scheme aims to find the required switching angles in order to eliminate the number of undesired harmonics. she is a complicated problem which consists of several nonlinear equations which have multiple local minima. in order to eliminate the higher number of undesired harmonics and as a result reducing the total harmonic distortion (...

Nowadays with increasing use of numerous nonlinear loads, voltage and current harmonics in power systems are one of the most important problems power engineers encounter. Many of these nonlinear loads, because of their dynamic natures, inject time-varying harmonics into power system. Common techniques applied for harmonics measurement and assessment such as FFT have significant errors in presen...

Flashover of polluted insulators in contaminated areas is one of the most important factors influencing the operation of transmission and distribution lines and finally line outages. Therefore, it is essential to prevent and detect flashover in the insulators. Hence, utilizing the insulator status monitoring systems and predicting their functions have absorbed a lot of attention over the recent...

This paper discuses the application of the revised IEEE-519 Harmonics standards to typical industrial facilities employing adjustable speed drives (ASDs). The harmonic generation characteristics of ASDs are described. Requirements for control of the harmonic currents are developed as a function of the ASD characteristics, overall plant loading level, power system characteristics, and power fact...

This paper presents a method based on the particle swarm optimization algorithm applied to estimate harmonic components in radial distribution feeders. It is important to mention that this method is not applied as harmonic state estimator, neither to estimate the total harmonic distortion at the substation. So, the proposed method can be employed to estimate the harmonic components in specific ...

The effects of using nonlinear low-gain opamps in switchedcapacitor delta-sigma modulators are analyzed. Using unconventional topologies, the state variables are made essentially uncorrelated with the input signal, hence opamp nonlinearity will cause very little harmonic distortion. Nonlinearity errors, whch are uncorrelated with the input, are called non-harmonic distortion. Using a correlated...

Optimized sampling technique to capture the harmonic distortion is the key for power factor measurement of nonlinear loads. Nowadays the power utilities and appliances are fully nonlinear in nature and thus the distortion of harmonics plays an important role and impacts the accuracy of many power factor measurement circuits and instruments. This study provides a cost effective design with a pro...

This paper analyzes the way to increase the energy efficiency of three phase converters applied to control AC motor drives, through the reduction of the total harmonic distortion (THD) of the output voltage and the reduction in the switching losses in the PWM inverter. The aim is to develop a system which selects the most adequate modulation technique required to simultaneously optimize the har...