In this paper

the loss factor detection as online monitoring method for inter-turn insulation fault of dry air core reactor is proposed on the basis of study of online monitoring technology for inter-turn insulation of dry-type air-core reactor.The calculation method of the electrical parameters and loss factor of the air core power reactor under normal circumstances and in the case of failure respectively is explored.The 10 kV series and parallel air-core reactors as taken as study object

and various electrical parameters and rate of change of two air-core reactors at different positions of two sets of power reactors in case of inter-turn short circuit are calculated.It is shown by the result that the insulation fault of the power reactor can be identified accurately by way of monitoring loss factor variation at different temperatures.