OPTIMAL CONTROL OF DIESEL ENGINE GENERATOR USING VARIABLE SPEED DOUBLY FED INDUCTION GENERATOR TO REDUCE FUEL CONSUMPTION

In regular operation, conventional DEG (Diesel Engine Generator) is designed with constant speed. Generally, DEG must operate at least 50% of its rated power. It causes fuel efficiency to worsen as fuel consumption remains constant despite the low power demand. Operating DEG in variable speed operation, where the engine’s speed is adjusted according to the size of the load, can reduce fuel consumption. DFIG (Doubly Fed Induction Generator) can operate at variable speeds, where power converters control the output. In this study, the optimal control of the DEG was developed using variable speed DFIG following changes in active and reactive loads. This system uses a direct voltage control method based fuzzy logic controller for DFIG via RSC (Rotor Side Con-verter). The study result shows that fuzzy logic controller reduces overshoot compared to the results of PI control. By applying the variable speed mode, fuel consumption can be reduced by up to 21.41%.