特高压变压器感应电压试验若干问题的探讨

变压器感应电压试验包括短时感应耐压试验(ACSD)和长时感应电压试验(ACLD)。随着电压等级的进一步提高以及绝缘水平的相对降低,在500kV电压等级中已初步暴露的ACSD和ACLD之间的矛盾越来越尖锐,并已超出GB和IEC等标准规定的范围。尤其对于特高压变压器,各国选择的感应电压试验要求存在极大的实质性差异。为了寻求感应电压试验的统一性原则并满足特高压变压器感应电压试验的要求,以遵循GB和IEC等标准规定的绝缘试验原则为基础,通过对不同电压等级变压器ACLD局部放电预加电压进行比较、调整和分析,指出ACLD局部放电预加电压应以1.1倍测量电压为下限,以85%额定短时感应耐受电压为上限。通过对不同电压等级变压器ACSD和操作冲击试验(SI)的绝缘试验要求和原则进行比较和探讨,指出对于特高压变压器,ACSD额定短时感应耐受电压不再具备确定性意义。为了兼顾特高压变压器的可靠性和经济性指标,应依据系统运行实际进行绝缘设计和试验验证,因此,建议针对特高压变压器开展以叠加操作冲击电压替代交流预加电压进行激发的ACLD试验研究。

Discussion on Induced Voltage Test for UHV Transformer

Along with the further increased voltage grades and relatively decreased insulation levels,the contradiction between ACSD and ACLD which has been exposed preliminarily in 500 kV voltage grade is becoming more acute.In order to seek unity of induced voltage test principles and satisfy the demands of UHV transformer induced voltage test,the ACLD partial discharge voltage in advance in different voltage grades was compared and discussed based on the dielectric test principles specified by GB and IEC.It is put ...