面向对象的运行中变压器抗短路能力评估方法与应用研究

Object-oriented Anti-short Circuit Ability Evaluation Method and Its Application of In-service Transformer

目前,电网中在运变压器抗短路能力的不足仍是威胁其安全运行的首要因素。在运变压器的抗短路能力,一方面取决于其初始抗短路能力,另一方面随着运行工况的变化而发生差异化改变,因此在运变压器实际抗短路能力诊断与评估是制造厂家、电力系统及高校共同关注的一个实际问题与研究热点。以变压器初始抗短路能力核算为基础,综合短路阻抗、频率响应、振动、绕组间电容量等变压器绕组变形诊断方法,提出了各种诊断结果的影响因子计算方法,引入了系统短路容量与不良工况修正因子,建立了面向对象的变压器抗短路能力评估模型,最后结合实际案例介绍了所提评估方法的应用效果。

The insufficient ability of anti-short circuit of in-service transformer now remains a primary threat of operation safety for transformer. The anti-short circuit ability of in-service transformer depends on its initial anti-short circuit ability on the one hand, and on the other hand it varies with the operating condition. Therefore, the diagnosis and evaluation of anti-short circuit ability of in-service transformer are the practical problem and research hotspot for manufacturers, power system and universities. This paper, based on the calculation of initial anti-short circuit ability and integration of the transformer winding deformation diagnosis methods such as the short circuit impedance, frequency response, vibration, capacitance between windings, the influencing factor calculation methods of each diagnosis results are proposed; moreover, short circuit capacity of power system and the modifying factors of adverse operating condition are introduced, and the evaluation model of object-oriented anti-short circuit ability for in-service transformer is built in this paper. Finally, the application effect of the proposed evaluation method is introduced by employing a practical example.