A micro-hydropower system model with PD load frequency controller for Resort Islands in the South China Sea

Abstract

A model of high-penetration micro-hydropower system with no storage is presented in this paper. This technology is designed in order to reduce the diesel fuel consumption and cost of electricity supply in a resort island located in the South China Sea. The optimal hydropower generation for this system depends on the available stream flow at the potential sites. At low stream flow, both the micro-hydropower system and the currently installed diesel generators are required to feed the load. However, when the hydropower generation exceeds the load demand, the diesel generator is shut down. Meanwhile, the system frequency is controlled by a secondary load bank that absorbs the hydropower which exceeds the consumer demand. This paper also presents a discrete frequency control system using proportional-derivative (PD) controller. The controller is employed in order to manipulate the system frequency by controlling the secondary load system. The simulation results indicate that a variety of load conditions can be satisfactorily controlled by the PD controller. Hence, this particular type of controller is suitable to be implemented in micro-grid systems for remote areas that require low cost and easy-to- maintain controllers.