System identification and control design of an alternative fuel engine for hybrid power generation

A throttle control system has been developed for a small V-twin engine used in a hybrid AC power generation system that incorporates two time variable power sources: a wind turbine and an internal combustion engine-generator combination. The control system utilizes a throttle actuator, a proportional integral derivative (PID) controller and software that determines desired power outputs (engine speeds) based on real-time measurements. A parallel approach to the design of the PID controller for system stability and proper performance is described. Transient response tests were performed from which suitable PID gain settings were selected by trial and error. In addition, frequency response tests were performed to develop models of the engine (system identification) at different operating points, which can then be used to analytically design the gains of the PID controller.