Current control method using a double band hysteresis

This paper presents a study on the double-band hysteresis current controller of the STATCOM (static synchronous compensator) used for reactive power compensation on a distribution network. Hysteresis controllers are intrinsically robust to system parameters, suitable for simple implementation and exhibit very high dynamic response. But in D-STATCOM, the current control using a conventional hysteresis controller has the disadvantage to be high switching frequency. In addition, the current error is not strictly limited. Therefore, in this paper, to reduce the switching frequency and current error, a double-band hysteresis current controller in stationary reference frame is proposed. The proposed double band hysteresis current control system was testified by the Borland C++ program and demonstrates the advantage of the proposed hysteresis current control method.