Measurement of power flow variations in Gaussian plane using phasor measuring unit

Abstract

In order to avoid large scale failure, it is necessary to monitor the widespread and complex performance of interconnected power grid system in real time. In case of bulk power system, the operation of Protective Relays and the Circuit Breakers are fast enough for secured performance but tracking of the system parameters during an event is beyond the scope of such devices. So, real time tracking before an event and quick analysis for potential failure of the system at the time of disturbances is quite difficult. Modernization of technology provides us with instruments to sample the continuous-time analog signal into discrete-time digital signal with the help of a device called Phasor Measuring Unit (PMU). As a result, it is also possible to estimate the dynamic phasor of the system and to determine the frequency and the Rate of Change of Frequency (ROCOF) of the system within a specific frequency zone. The purpose of this paper is to present a mechanism for continuous observation of the interconnected power system within a specific frequency zone and detection of its nature with improved accuracy using Phasor Measuring Unit (PMU). Having the Rate of Change of Frequency as the prime detector of disturbances at the interconnected grid system in Gaussian plane, this should facilitate the continuous observation and a system protection scheme which is more efficient. This should minimize the sudden damages of the system equipments due to abnormal behavior of the bulk interconnected electrical power system.