Research on Overloading Protection of Permanent Magnetic Coupler in Coal Mine

In this paper, with simulations and experiments analysed by the software of Ansoft Maxwell, research on overloading protection of permanent magnetic coupler in coal mine is carried out and the conclusive curves of mechanical characteristics are plotted through experimental data. The conclusion can be gained from mechanical characteristic curves: when the output value of torque reaches the maximum torque of magnetic coupler, the output torque and speed will drop along with increases of the slip, and the input power value of motor is less than the power value at the time when the motor torque value is at the maximum. It explains that the magnetic coupler has the function for overloading protection.