Analyses and Monitoring of Power Grid

Abstract

Power system analyses and monitoring of power system engineering are as essential as oxygen for human beings. This innovative approach deals with a 132 kV grid simulation in electrical transient analyzer program (ETAP). The existing power distribution system in Pakistan consists of approximately six thousand 11 kV feeders, which are mainly analyzed by software FDR-ANA (Feeder Analyses). This software does not have capability to provide comprehensive analyses for integrated power system. The case under study is 132 kV grid situated in Gujranwala electric power company (GEPCO), one of the distribution companies (DISCO’s) of Pakistan electric power company (PEPCO) which has been selected for comprehensive analyses using ETAP software. This software performs numerical calculations of large integrated power system with fabulous speed, besides generating output reports. In a developing country like Pakistan it is first time that analyses based Off-line monitoring has been made, which includes load flow, harmonic, transient, short circuit and ground grid analyses. In load flow analysis, current flowing in every branch, power factor, active and reactive power flow, line losses, voltage magnitude with angle etc. have been calculated. During harmonic analysis, distorted current and voltage waveforms along with their harmonic spectrum caused by non-linear loads have been recorded. Transient analysis has been performed to record different waveforms like variation in bus frequency, bus real power loading, bus voltage angle, and bus reactive power loading for short interval of time during transient conditions. In ground grid modeling, step, and touch potentials have been calculated in comparison with set standards. While performing short circuit analysis, all the possible short circuit faults like line to ground, double line to ground, 3-phase faults etc. on ½ cycle, 1.5 to 4 cycle, and 30 cycle networks have been performed to record the short circuit currents. These analyses have been executed using ETAP software, based upon historical data obtained from original system that will be very helpful for system security and reliability.