Study on variation law of electrical parameters in dry hollow reactor inter-turn short circuit fault

The main factors affecting the accident of dry-type air-core reactors are the inter-turn short circuits. In order to realize the diagnosis of the inter-turn insulation, the change of the electrical parameters of the dry-type air-core reactors in the inter-turn short circuit fault is studied. The research shows that in the process of inter-turn short-circuiting, the inductance becomes smaller and the equivalent impedance becomes larger. And as the degree of failure increases, the former continues to decease and the latter keep going to increase. Under the same fault case, the variation of the equivalent impedance is much larger than the variation of the inductance. It can be seen that the equivalent impedance can be used as a diagnostic parameter for the inter-turn short circuit of dry-type hollow reactor, which provides a new way for monitoring the inter-turn short circuit fault in the reactor.