AUTOMATIC PRIORITY BASED LOAD SHEDDING MANAGEMENT

Abstract

Electric load shedding is implemented to maintain the generation power margin at rated level when load demand is higher than electric supply. This requires mainly when parallel source fails to supply the power. This prevents the widespread system collapse when a fault occurs. The scope of study consists of system analysis, design and simulation. When the main grid got tripped on any fault then entire load will be shifted over a single alternator, which may cause alternator to be overload, and to prevent the collapse of the total load, predetermined amount of load will be removed. Important design considerations for this scheme shedding steps, size of load shed at each step and frequency relay settings. Load restoration after load shedding can only be executed after the system has recovered completely and its normal frequency is restored. Loads should be restored in small blocks sequenced by time delay between successive restorations to allow frequency stabilization. A case study is carried out in a Petrochemical industry in Taloja MIDC, Mumbai, Maharashtra, where a load shedding scheme is designed for its cogeneration plant.