Harmonics in distribution system of an educational institution

Many commercial and industrial power systems are being burdened by the proliferation of sensitive computing equipment like personal computers, uninterruptable power supplies, CAD workstations and other nonlinear loads like television sets, fluorescent lamps, variable frequency/speed drives. An important concern to the power engineer is the effect of harmonic distortion in the voltage and current waveforms, caused by the nonlinear loads, on the power distribution equipment in the system. In this paper an attempt has been made to study and analyse the harmonic distortions caused by certain typical nonlinear loads of an educational institution-Regional Engineering College, Calicut. The typical loads include computer centre, electrical machine laboratory, power laundry, air-conditioning plant, power distribution centre supplying the entire campus and a small scale industrial unit. The restarts showed that the total harmonic distortions caused by these loads far exceeded the standard limit of THD less than 5%.