Wind hub reactive resource coordination and voltage control study by sequence power flow

A simple and effective method for studying wind hub reactive resource coordination and voltage control of the point of interconnection (POI) is presented. The method is illustrated through a study example of a wind hub on the Bonneville Power Administration´s (BPA) transmission system. The hub substation includes six wind plants interconnected to a ring bus, built in the middle of a 230 kV transmission line. The results show a clear picture how the discrete reactive shunts switch to maintain dynamic reactive margin as the wind plants ramp up and down. Reactive margin represents an important metric for assuring reliable grid operation from a voltage stability perspective. The primary focus is to present the sequence power flow study method.