A Static Voltage Stability Margin Evaluation Approach for Coordinated Operation of Grid-Tied Wind Power, PV and Energy Storage Stations

Static voltage stability of power grids will become more sensitive to the coordinated operation of renewable energy resources (RESs) and energy storage systems (ESSes) due to their different output characteristics. This paper presents a generalized approach for static voltage stability evaluation under coordinated operations of wind power, PV and energy storage stations. First, a combined model for coordinated operation of stations which describes the output characteristics of active and reactive power is established. Then, the integration point of stations is optimized by modal analysis such that the most sensitive bus in the system can be located. Afterwards, the static voltage stability margin can be evaluated for load buses via impedance modulus margin index (IMMI). Furthermore, impact of penetration rates and penetration rate ratio among wind power, PV and energy storage stations on static voltage stability margin is investigated. To validate the effectiveness of proposed method, a standard IEEE 14 bus test system is studied and numerical results are presented.