A Remedial Action Scheme to Prevent Mid/Long-Term Voltage Instabilities

The main objective of this article is to propose a special protection system (SPS) execute efficient remedial actions prevent mid-term and long-term voltage instabilities. In method, when the operating point (OP) leaves normal operation state, proposed SPS initiated required corrective bring OP back state maintain bus voltages above prespecified thresholds. Considering local nature Volt/Var control in order fast actions, approach, generation rescheduling or load shedding procedures were selected based on electrical distance concept. This allows for with highest impact volt/var control. addition, procedures, method uses ability utility-scale photovoltaic resources, which can change their quickly. plays major role maintaining stability power systems. Efficiency algorithm was validated through several scenarios performed IEEE 39-bus, Nordic32, PST 16 test systems using DIgSILENT PowerFactory software. Results these dynamic simulations comparison some previously published methods show effectiveness timely executing appropriate stability.