출력변동에 대응한 유도발전기의 역률 보상 제어

Abstract

Induction generators are widely used in micro hydroelectric power plants. When the flow rate and the head change in the power plants, it becomes a parameter that changes the output of the induction generator. Induction generator has a low power factor even when operated at rated output with an inductive load. Also, if the induction generator is operated lower than the rated value or its output power is fluctuated, the change in the power factor becomes larger at a lower power factor. Therefore, a power factor compensation device such as a single capacitor or STATCOM is applied for power factor compensation. When the generator output is fluctuated, the converter voltage of STATCOM has the characteristic of fluctuating in conjunction with it. In this study, we propose the constant voltage source control method in STATCOM for power factor correction of induction generator and its feasibility is verified by the simulation in which the performance of power factor compensation by the capacitor, STATCOM without constant voltage control and STATCOM with constant voltage control are simulated and quantitatively compared. As a results, we confirmed that the STATCOM with constant voltage control can improve the power factor of induction generators a little comparing to the single capacitor or STATCOM without constant voltage control even if the generator output is fluctuated.