牵引变压器绕组变形在线检测方法研究

Study on on-line Detecting of Deformation of Transformer Winding

国内外的研究和统计表明,变压器绕组变形是电力系统安全运行的一大隐患,通过测量变压器绕组短路电抗来判断变压器绕组是否变形是一种有效的方法。本文提出了2种通过在线监测原、次边的电压和电流,实时计算绕组的短路电抗来判断变压器绕组变形的方法,并对电气化铁路主要接线形式的牵引变压器绕组变形的在线监测方案进行了设计。论文分析了互感器误差对短路电抗测量结果的影响;通过变压器建模,分析了磁滞特性和负载变化大小对短路电抗测量结果的影响,验证了该方法在工程应用上的可行性。

The domestic and oversea research and statistics indicate that transformer winding deformation is a hidden trouble for the safe running of the electric power system, and the method via measuring the short-circuit reactance of the power transformer to estimate the deformation is effective. Two kinds of methods for detecting the winding deformation of the power transformer are proposed in the paper. These methods are based on on-line monitoring of primary and secondary currents and voltages to carry out real-time computation of the short-circuit reactance of windings. The on-line monitoring scheme is designed for traction transformers with the main type of connection used on electric railways. The effects CT and PT errors, hysterics and load variation on short-circuit reactance are discussed also. The proposed methods have been proved feasible in engineering.