This paper presents a Selective Harmonic Elimination-PWM technology (SHE-PWM) employing H-Bridge multilevel inverter configuration. In this method variable DC voltage is used and the lower order harmonics are eliminated, without affecting the structure of the inverter. This method gives constant switching angle, so it reduces the number of steps required for offline calculation. The proposed me...

Unified power quality conditioner is one of the advanced forms of power conditioning device, which is a combination of back to back connected series APF and shunt active power filter (SAPF) connected to a common DC link voltage. This topology will facilitates this device to have a reduced dc-link voltage without reducing its compensation capability. This device is mainly used in improving the p...

When the harmonic spectrum is known, or at least can be measured with a certain reliability or predicted, the additional losses can be easily calculated. The process of calculation should be made through the following steps: 1. Determination of all the components of additional losses due to the presence of harmonics. 2. Determination of the harmonic spectrum, either by measurement or by estimat...

This paper presents a critical survey of the reference current generation (RCG) methods for harmonic and reactive power compensation for the electrical distribution systems. A critical review of the pq method, the d-q(id-iq) method, the p-q-r method, the UPF method and the FBD method are presented for the sake of comparison. In order to mitigate the deficiencies of these existing methods, the m...

This project deals with the application of distribution generation with energy storage system connected to the low– voltage microgrid by coupling inverter for simultaneous energy management and other aucillary services that include the compensation of power quality disturbances. To address inaccurate power sharing problems in autonomous islanding microgrid, an enhanced droop control method thro...

Three-Phase four-wire distribution systems are facing severe power quality problems such as poor voltage regulation, high reactive power and harmonics current burden, load unbalancing, excessive neutral current, etc.This creates excessive neutral current both of fundamental and harmonic frequency and the neutral conductor gets overloaded. By integrating phase shifting into an extremely low zero...

The paper presents a three-dimensional space-vector-modulation scheme for three-phase four-wire active power filters. The focus is on the implementation of a fixed frequency pulse width modulation (PWM) scheme with a minimum number of switch commutations per period and maximum DC bus voltage utilisation. For three-wire applications, space vector modulation is known to provide better utilisation...

-A three-phase hybrid series power filter is constituted by a series active filter and a passive filter connected in parallel with the load. The control strategy is based on the “dual formulation of the electric power vectorial theory”. The proposed algorithm eliminates the current harmonics of supply. It also improves the power factor and harmonic compensation features of the associated passiv...

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...