Reverse Power Protection of an Alternator

Power plant generators are important components of an electrical energy system. They should be constantly monitored and protected in order to maintain the quality and reliability of the power supply. Otherwise generator may operate incorrectly resulting in poor power quality and instability during events like faults, equipment failure, reverse power flow(RPF) etc., the presence of large distributed energy resources is the major cause to the reverse power flow during low loads/excess generation at distribution level. If reverse power flow (RPF) is not resolved, it leads to incorrect operation of generators or affect connected devices. Therefore it is necessary to monitor and prevent reverse power flow condition. This paper deals with reverse power flow protection, here hardware model representing generator connected to the grid is developed using low rating permanent magnet motors, sensors, PIC16F877A microcontroller, regulated power supply, relay driver, Liquid Crystal display (LCD) and relay, to monitor and protect generator from RPF.