CAJ | 학술논문

为实现换流变压器故障诊断，研究交流与直流电压比例对油纸绝缘放电特性的影响对换流变压器的故障诊断判据选取具有实际工程意义。因此该文搭建了一套交直流复合电压作用下油纸绝缘气隙缺陷局部放电测量平台，通过多次试验得到了局部放电特征与交直流复合比例的试验关系；另外建立了油纸绝缘气隙缺陷的物理模型，从理论上分析了比例与放电特征关系的仿真结果。试验测量和理论仿真结果相同：随着交流和直流叠加电压中直流成分的增大，脉冲重复率和放电量不断减小；交流时的放电起始电压低于交直流复合电压作用时的起始电压，而且直流比例越高，起始电压越高；随着交流中直流成分的增加，放电起始相位从交流正负半周过零点附近向负半周期峰值附近移动，换流变压器不同位置的绝缘问题应该采用不同的诊断依据。
위실현환류변압기고장진단，연구교류여직류전압비례대유지절연방전특성적영향대환류변압기적고장진단판거선취구유실제공정의의。인차해문탑건료일투교직류복합전압작용하유지절연기극결함국부방전측량평태，통과다차시험득도료국부방전특정여교직류복합비례적시험관계；령외건립료유지절연기극결함적물리모형，종이론상분석료비례여방전특정관계적방진결과。시험측량화이론방진결과상동：수착교류화직류첩가전압중직류성분적증대，맥충중복솔화방전량불단감소；교류시적방전기시전압저우교직류복합전압작용시적기시전압，이차직류비례월고，기시전압월고；수착교류중직류성분적증가，방전기시상위종교류정부반주과영점부근향부반주기봉치부근이동，환류변압기불동위치적절연문제응해채용불동적진단의거。
In order to realize the fault diagnosis for converter transformer, to study the influence of ratios of AC and DC voltages on partial discharge (PD) characteristics has practical engineering significance for diagnosis of converter transformer. A set of platform was built for PD detection under AC and DC voltage. The relationship between ratios of AC and DC voltage and PD characteristics was obtained by several tests and simulated by building physical model. The experimental measurement and theoretical simulation results are the same: the pulse repetition frequency and PD amount decrease with the DC voltage increasing. But the PD inception voltage increases when DC voltage becomes larger. In addition, the PD phase moves form two locations to just one part in negative half cycle. So for converter transformer, the diagnosis basis should distinguish with the insulation problem at different location.