应用复合阻抗比较原理的广域方向保护算法  

A Novel WADP Algorithm Using Composite Impedance Comparison

作　　者：李振兴[1] 吴李群[1] 王欣[1] 李振华[1] 

机构地区：[1]三峡大学电气与新能源学院,湖北省宜昌市443002

出　　处：《电网技术》2016年第3期938-943,共6页Power System Technology

基　　金：湖北省自然科学基金项目(2014CFB680)~~

摘　　要：广域差动保护和广域综合阻抗保护均能够利用广域多信息实现快速识别故障,具有受过渡电阻、分布电容等影响较小的优点,但需要广域信息严格同步,特别是保护范围存在负荷电流时保护明显存在误判。以解决上述问题为出发点,提出基于复合阻抗比较原理的广域方向保护新算法。该算法依据常规纵联电流差动保护的同步信息,利用单端母线电压与线路差电流比值提出复合阻抗定义,进一步分析区内外故障下复合阻抗的动作特性,构建故障区域判断和故障支路判断方向信息,并应用广域多源方向信息提出广域方向保护新算法。该算法既保留了广域差动保护和广域综合阻抗保护的优点,同时克服了广域严格的同步性、高阻接地、负载电流等的影响;从工程意义上讲保护系统通信量小,易于实现。基于IEEE 10机39节点系统仿真结果验证该算法的有效性。Wide-area integrated impedance protection using wide-area information is able to quickly identify fault, and not affected by distributed capacitance and grounding resistance. But it requires strict wide-area synchronous information and special processing when there is any load current in protected area. In order to solve above problems, this paper puts forward a new wide-area direction protection（WADP） algorithm based composite impedance comparison. This algorithm, using synchronicity of conventional pilot current differential protection, calculates ratio of bus voltage and differential current of line, and the ratio is redefined as composite impedance. Comparison criteria are analyzed based on normal, internal and external fault states. The new algorithm retains advantages of original wide area integrated impedance, and overcomes dependency for strict wide-area synchronicity and impactof load current. Finally, protection scheme of WADP is analyzed. Simulation results in IEEE 10 machine 39 node system verify effectiveness of the proposed algorithm.

关 键 词：广域方向保护 复合阻抗 广域同步性 区域方向 支路方向 

分 类 号：TM77[电气工程—电力系统及自动化]