Harmonic analysis of Electrical systems helps to determine the presence of different harmonics present in the power supply to different loads. These harmonics are generated by different electronically driven electrical devices, transformer energisation, switching of capacitor banks etc. Such analysis also helps in finding a method to filter the harmonics to improve the power quality. Satcon provided such services for 33kV, 22kV and 400V Electrical systems in various projects. We do analysis by ETAP software.