Power Quality (also known as PQ) is a highly newsworthy issue. Increasing use of semiconductor based electronic equipment & non-linear loads (such as computers & their peripherals, data servers, adjustable speed drivers, arc furnaces etc.) and rapid integration of non-conventional energy sources into grid network throws new challenges for the PQ environment.
The characteristics of electricity like frequency, magnitude, waveform, and symmetry are subject to variations during the normal operation in a supply system due to changes of load, disturbances generated by certain equipment and the occurrence of faults which are mainly caused by external events. These characteristics vary at random with time, or reference to any specific supply terminal, and location with reference to any given instant of time due to sources of disturbances like - atmospheric phenomena, environmental conditions. Sometimes the equipment installed at the premises of an electricity user can inject disturbances (e.g. harmonic or inter-harmonic distortion, voltage fluctuations etc.) into the distribution networks.
These power quality issues may effect end users, equipment & system manufacturer, designers of plants & installations, electricity distributors, public authorities and general public. Outcome of some surveys have revealed significant losses to industries due to poor power quality. Variation in voltage & frequency and waveform distortion (in other words harmonics) are the critical power quality issues.
The quality of electrical power is an important contributing factor to the development of any country and this can be achieved through continuous power quality monitoring which helps detect, record and prevent power quality problems.