Belt conveyor is a towing continuous transportation equipment for the delivery of block, granular and bulk material, widely used in coal, metallurgy, mining, ports, building materials, chemicals, light industry, petroleum, transportation and other industries. Among them, the large inclination downward belt conveyor is suitable for the transportation in the underground coal gateway, tunnel excavation, inclined shaft hoisting, open pit mine and ground transportation system, so it is the ideal supporting equipment for coal mining mechanization and can work in the environment -10 ° C ~ + 40 ° C.

The downward belt conveyor transports the material from higher spot to lower spot and only need to overcome the friction, so it is with light load. If the gravitation of conveyed material in the running direction is greater than the friction created during the belt conveyor running, the motor rotor will be passively accelerated under the drag of the material. When the motor speed exceeds its own synchronous speed, the motor in turn will generate electricity and produce braking force in order to prevent the motor speed from further rising, that is, the potential energy of the falling material is turned into electrical energy. Therefore, a series of measures can be used to re-distribute the electric energy generated by the downward conveyed materials to the power grid.