同塔四回线路分布参数的测量

A New Approach to Measure the Distributed Parameters of Quadruple-Circuit Transmission Lines

提出一种长距离同塔四回线路分布参数的测量方法。建立了同塔四回线路的分布参数模型,引入变换矩阵对参数矩阵和传输线方程进行线性变换。使用拉普拉斯变换法进行求解,推导了分布参数的数学解析式。通过四回线路双端同步或非严格同步测量得到电压和电流数据,对四回线路的分布参数进行精确计算。采用增量法减小感应电压干扰对测量结果的影响。利用PSCAD软件验证了该方法的有效性。仿真结果表明,该方法克服了单端法测量步骤繁琐的缺点,也克服了现有双端法对测量数据同步的高度依赖,可在双端测量数据非严格同步的状态下精确测量线路的分布参数。该方法充分考虑了线路的分布效应,极大地简化了测量过程,能够在线路停电和带电条件下准确测量长距离线路的正序参数和零序参数。

A new approach for measuring the distribution parameters of long distance quadruple-circuit transmission lines was proposed. A transformation matrix was introduced for the linear transformation of the distributed parameter matrixes and the transmission line equations. The transmission equations were solved by Laplace transform method and the analytic expressions of the distribution parameters were deduced. The distribution parameters can be accurately calculated by using two-end synchronous or asynchronous sampled voltages and currents of the quadruple-circuit lines. The incremental method was used to decrease the influence of interference on the measurement results. PSCAD software was employed to verify the proposed method. The simulation results suggest that the proposed method overcomes the complexity of the measurement process of the single-end methods and the high dependency of data synchronization of the existing two-end methods. The proposed method can accurately measure the distribution parameters of the lines in the condition of asynchronous measurement. The proposed method which takes fully account of the distribution effect simplifies the measurement procedure significantly, and can accurately measure the positive sequence parameters and zero sequence parameters of long distance lines in off-line or on-line situations.