电网PQ扰动分解的戴维南等值

P-Q Disturbance Decoupled Thevenin Equivalent for Power Grids

因实际电网稳态电路中的发电机节点有电压源和受控电流源间耦合的性质,因此其并不能直接适用于戴维南定理的条件。对此,基于叠加原理,将电网稳态电路分解为无功扰动平衡电路和有功扰动平衡电路,发电机节点也随之分解为电压源和受控电流源。基于电网节点电压方程和欧姆定律,分别给出2个分解电路的戴维南等值解析模型,两者叠加形成PQ扰动分解的戴维南等值。由于电网无功平衡和有功平衡的调控、传输以及它们对节点电压影响规律的区别,相比与传统电网戴维南等值模型,PQ扰动分解的戴维南等值不仅能更准确地拟合电网稳态电路,也能为后续的分析和控制提供更多、更准确的信息。算例结果表明该方法的准确性和有效性,其是电网戴维南等值方法在实际电网应用理论基础研究上的一个重要进展。

Because the generators in the steady-state circuit of the actual power grid have the nature of the coupling between the voltage source and the controlled current source,it cannot be directly applied by the Thevenin theorem.In this regard,based on the principle of superposition theorem,the steady-state circuit of the power grid was decomposed into a reactive power disturbance balance circuit and an active power disturbance balance circuit,and the generator was also decomposed into a voltage source and a controlled current source.Based on the grid node-voltage equation and Ohm’s law,the Thevenin equivalent analytical models of the two decomposition circuits were respectively given,and the two were superimposed to form the Thevenin equivalent of the PQ disturbance decomposition.Due to the difference between the regulation and transmission of reactive power balance and active power balance of power grid and their influence on voltage,compared with the traditional power grid Thevenin equivalent model,the Thevenin equivalent of PQ disturbance decomposition can not only fit the steady-state circuit of the power grid more accurately but also provide more and more accurate information for subsequent analysis and control.The results of calculation examples show the accuracy and effectiveness of this method,and it is an important development of the Thevenin equivalent method in practical power grid application theoretical foundation research.