Controlling chaos and voltage collapse using an ANFIS-based composite controller-static var compensator in power systems

► Chaos and voltage collapse appear in power systems due to heavy loading and disturbing of energy. ► ANFIS-based composite controller-SVC was proposed to suppress chaos and voltage collapse in power systems. ► By using an ANFIS-based SVC the load voltage was maintained to setting value. ► Furthermore, the proposed method was able to increase the loading margin. Chaos and voltage collapse exist in power systems due to critical loading and disturbing of energy (DE). These phenomena cause instability in power system operation and must be avoided. In this paper, an ANFIS-based composite controller-static var compensator (CC-SVC) was proposed to control both chaotic oscillations and voltage collapse. The ANFIS-based CC-SVC was proposed because its computation was more efficient than Mamdani fuzzy logic controller. Adaptive network parameters were obtained through a training process. The controller parameters were automatically updated by off-line training. Both chaos and voltage collapse were able to control and suppress effectively by the proposed method. Furthermore, the load voltage was held to a set value by adjusting the supplied reactive power. When the reactive load was increased, the SVC susceptance and reactive power supplied by the SVC also increased. The proposed method was able to maintain the load voltage and to increase the loading margin.