Analysis of Generated Harmonics in DFIG Driven by Wind Turbine during Linear & Non-Linear Load

Abstract

As far as demand of electricity increasing, power generation from conventional and non-conventional sources also increasing. When numbers of power unit increases, the interconnection of these units also get complex and factor of overcurrent and reactive poweralso increases. For which renewable energy sources are playing a vital role to full fill electricity demand. The wind energy draws attention because of its low cost. The annual percentage increase in the wind farm is very high and now India is the fifth in the world with an installed capacity of about 21262 MW [1]. The Ministry of New and Renewable Energy (MNRE), together with the distribution companies of Gujarat, Maharashtra and Tamil Nadu, has granted a wind capacity of 7.6 Gw in the last 15 months and intends to grant an extra 10 Gw in the year FY 2019 FY 2020[2]. It is found that when a non linear load is connected with the wind connected Double Fed Induction Generator (DFIG) system then there is a large amount of harmonics present in the generated electricity[3]. The proposed work shows the comparison of generated harmonics in electrical energy by wind connected DFIG system using hybrid active filter during linear and nonlinear load. This work has a simulation of Grid Side Control (GSC) and Rotor Side Control (RSC) with hybrid active filter to reduce the harmonics in case of linear and non linear load. The result of this work showing that the value of harmonics reduced up to 4.96% from 29.66% when non linear load is connected with the system. It also shows that the value of harmonic is 0.14% when non linear load is not connected to the system. Many researches are going on for developing filters which can suppress the level of harmonics more than the Hybrid active power filter. The model for the proposed work is developed in MATLAB R2018a version. The model is drawn in simulink part of the MATLABSoftware.