CAJ | 학술논문

提出一种利用短路点自阻抗分析500 kV电网短路电流超标机理的方法,并应用于短路电流限制措施的适应性研究.基于二端口网络理论,构建双端电源等值电路,从短路点自阻抗各组成要素的物理意义角度分析不同位置、不同类型短路电流的主要影响因素,揭示其超标机理.500 kV侧短路电流主要取决于500 kV侧电网结构,因此其限制措施主要是改变500 kV侧电网参数;220 kV侧短路电流受变压器等值阻抗和220 kV电网结构的影响,但不同站点受二者影响程度不同,应根据不同影响程度采取相应的措施以增大变压器等值阻抗或改变220 kV侧电网参数.应用于广东500 kV电网短路电流分析和限制措施的研究结果证明了其正确性和实用性.
제출일충이용단로점자조항분석500 kV전망단로전류초표궤리적방법,병응용우단로전류한제조시적괄응성연구.기우이단구망락이론,구건쌍단전원등치전로,종단로점자조항각조성요소적물리의의각도분석불동위치、불동류형단로전류적주요영향인소,게시기초표궤리.500 kV측단로전류주요취결우500 kV측전망결구,인차기한제조시주요시개변500 kV측전망삼수;220 kV측단로전류수변압기등치조항화220 kV전망결구적영향,단불동참점수이자영향정도불동,응근거불동영향정도채취상응적조시이증대변압기등치조항혹개변220 kV측전망삼수.응용우엄동500 kV전망단로전류분석화한제조시적연구결과증명료기정학성화실용성.
A method is proposed to analyze the short-circuit current over-limited mechanism for 500 kV power systems using the self-imdedance at the short-circuit point.The method can be applied to assess the adaptability of short-circuit current limiting measures. Based on two-port network theory, an equivalent circuit with only two nodes is formed, using which the main influencing factors in short-circuit currents of different locations and fault types from the physical meaning of self-impedance composition at the short-circuit point are analyzed, and the over-limited mechanism is revealed. As is indicated,the short-circuit current at the 500 kV side mostly depends on the grid structures at the 500 kV side,correspondingly the limiting measure is mainly to change the parameters of the 500 kV power grid.The short-circuit current at the 220 kV side is affected not only by the equivalent impedance of transformers but also by the grid structures at the 2 20 kV side,and the sensitivities of the two aspects vary at different substations.According to the various sensitivities,the limiting measure should be adapted to increase the equivalent impedance of transformers or to change the paramet'ers of the 220 kV side.The proposed method has been applied t0 the short-circuit current analysis and the limiting measures assessment of Guangdong 500 kV power grid.It is proved that the method is valid and with high practicability.