ADAPTIVE GOVERNOR CONTROL AND LOAD SHEDDING SCHEME FOR AN INCINERATOR PLANT

This paper presents an adaptive control strategy for the governor system of an incinerator cogenerator to maintain the steam pressure and system power frequency. Due to the unstable steam generation in incinerator plants, the turbine valves have to be controlled adaptively to keep the boiler steam pressure constant for normal operation. After tie-line tripping caused by utility faults, the governor system must be operated with constant frequency control for the islanding system. By this way, the surplus steam supply to turbines will be bypassed effectively. For the islanding operation, the deficiency of steam generation is then supplemented by boilers. To maintain the system stability after transient disturbance for the isolated system, the load shedding scheme is designed by considering the under steam pressure protection. According to the transient stability analysis, the system frequency can be restored successfully after tie-line tripping with the adaptive change of governor control system from the constant steam pressure mode to the constant frequency mode.