Integrated Busbar, Transformer And Feeder Backup Protection Based On Wide Area Voltage Measurements

The concurrent deployment of PMUs and fast communications has facilitated the development of new protection strategies to meet the demands of the modern power grid. A recent paper introduced a new voltage-based protection algorithm that uses active power differential and sensitivity analysis (APdSA) to detect short circuit faults. The algorithm is applied for the protection of active distribution networks and microgrids. This paper explores the suitability of the APdSA to a high voltage (HV) network model comprising transmission lines and transformers. It is shown that a single APdSA-based relay can provide integrated but selective protection of a busbar and all transformers and feeders connected to it. The APdSA algorithm is differential in principle but delays due to PMU reporting and communication latencies make this algorithm suitable as backup protection for the protection zone integrating all the components terminating at a busbar, including the busbar itself.