Power Quality Analysis of Electrical Power System Involving Grid Connected PV System

Abstract

Power Quality is an essential aspect for reliable operation of power grid including photovoltaic based generation. This specifically affects performance of the system and results into Financial losses to utilities. Power Quality problems which includes mainly the issues like harmonics, adversely affects electrical machines, protective devices, communication device etc. The project work focuses on real time problem of injection of harmonics into power network. For addressing the said issue the solar plant of 5 MW capacity has been considered. The PV plant includes 10 inverters each of 500 kW connected to 33 kV bus locally. The power produced by plant is explored via 4 km cable at 220 kV, where the other 400 MW gas based power plant is also running in parallel at the same bus. It is observed that due to injection of harmonics and resonance at particular natural frequency after certain irradiation and hence generation, at specific time of day several inverters are tripped simultaneously. Voltage variation has also been observed. To address the said problem, the project aims at identification of harmonics and res- onant frequency, and also the design of filter to mitigate the harmonics. In order to deal with the problem, firstly simulation model has been developed in software named NEPLAN, for investigation of order of generated harmonics. From which based on identification of so, active and passive filtering techniques are adopted to mitigate the same. Simulation environment used for active filtering is PSCAD/EMTDC.