一种新的机车主变压器铁心状态在线监测方法

A New Online Status Monitoring Method for Iron Cores of Locomotive Main Transformers

提出一种通过在线估测机车主变压器铁心损耗来实时监测机车主变压器铁心工作状态的新方法。根据磁动势守恒定律,利用电力机车主变压器综合测试和故障诊断系统在线测量主变压器各端口的电气量,来实时估测主变压器的铁损。磁化电流作为其中一个不可直接测量的关键量,该文通过空载试验建立铁心等效非线性电感的数学模型来获取。通过对比发现,该建模技术计算简单、易于实施、适用性好且精确度更高,且在某型机车主变压器的试验中总体误差小于0.02%。最后通过对某型机车主变压器进行现场试验,分别在正常状态和硅钢片片间短路故障下,验证了提出的在线状态监测技术的有效性和可行性。

A novel method is proposed to monitor the working status of iron cores of locomotive main transformers timely through online estimating the iron core losses of locomotive main transformers. According to the law of conservation of MMF, the electric locomotive main transformer comprehensive test and fault diagnosis system was used to obtainthe electrical data from terminals that can estimated the core losses. The magnetizing current, as one of the key parameters, is acquired from an equivalent non-linear model under the no-load test. By comparison, it is verified that the inductor model proposed here is simple in calculation, easy to implement, owns good applicability and high accuracy （the error is below 0.02% for a main transformer）. Finally the proposed online status monitoring method is proved to be feasible and effective through field tests on a main transformer under normal status and inter-laminar fault status respectively.