The reactors are running in medium voltage system

it often use dry-type air-core construction.Maybe the reactor is less important than transformers and other devices

at present

there is no many analysis and research on the reactor accident and protection. The existing protection device can not timely and accurately acting for the reactor fault

the existing protection device for reactor failure is not timely and accurately for action

therefore the dry-type air-core reactor is running under the no protection state.Once the accident occurs

the fault reactor has not been removed in time

it may lead to greater secondary disasters and losses. In order to solve this problem

the author studies the monitoring theory of interturn short circuit for dry-type air-core reactor

compiles control algorithm by Labview software

simulates the magnetic field variation when reactor occurs interturn short circuit

develops protection devices and a reactor model machine for testing the interturn short circuit. Finally

according to the simulation result and practical feasibility

the suggestion is given for the application of engineering.