火电-新能源组合系统的暂态功角稳定和暂态过电压耦合特性分析OA

In a thermal power-renewable energy combined transmission system,the transient power rotor angle instability of thermal power units and the transient over-voltage at the renewable energy generator terminals are important issues that limit the transmission capacity.First,an analytical equation for the power rotor angle variation of thermal power units considering the negative impedance characteristics of new energy is established,and the new transient power rotor angle stability characteristics of thermal power units after the integration of new energy are analyzed.Secondly,based on the Thévenin equivalent and vector analysis method,the transient over-voltage at the new energy machine terminal is analyzed,and the influencing factors of transient over-voltage are discussed.Next,through formula analysis and electromagnetic transient simulations,the coupling relationship between two types of transient over-voltages is highlighted.Finally,using a practical engineering case as an example,this study analyzes the dominant risk modes under different scenarios,and proposes operational modes under two integrated risk constraints.The research results provide technical references for the safe and stable operation of thermal power-renewable energy combined energy bases in the new situation.