Tracing Voltage Collapse Point for Non-uniform Loading Using Holomorphic Embedding

The voltage stability analysis of the power system deals with the analysis of the bus voltage drop as the system experience increase in load and the system leads to voltage collapse in the worst case. To avoid the system from approaching such critical point, it is necessary to trace that critical point (voltage collapse point). The classical homotopy continuation methods that trace the trend in voltage change due to load variation are based on a Jacobian calculation, which becomes singular near the voltage collapse point. In addition, switching from one load flow calculation method to others is required to trace the power vs voltage curve and voltage collapse point. Consequently, to overcome the shortcomings of the conventional method and trace the voltage collapse point in non-uniform loading at load buses (more realistic situation), a novel extended holomorphically embedded power flow (EHEPF) method is proposed and validated using 4-bus system efficiently.