Development of Digital Control Systems of Small High-Frequency Generators

摘要

This paper presents the design of a compact control system applied to a small capacity engine-generator system. In the engine-generator system, a high-speed gasoline-engine drives a permanent magnet synchronous generator to rotate at the same speed (about 3000 rpm) and 400Hz AC is generated. Then the generator's output is converted to 220V/50Hz AC with a diode rectifier and a single-phase full-bridge inverter. A speed governor, which consists of a digital speed controller and an actuator, is developed to keep the DC link voltage constant. To improve system's response performance, a fuzzy-PID control algorithm is used in the speed controller. Experiments show that the output has less harmonic and good stability at various loads.