Introduction
The belt conveyor is a kind of continuous transportation equipment with traction, suitable for coal, metallurgy, mining, port, building materials, chemical industry, light industry, petroleum, and transportation industries. It can be used to transport lump, granular and bulk materials. The belt conveyor with large dip angle is suitable for various transportation conditions such as cross-heading underground coal mines, roadway tunneling, uphill&downhill transportation roadway, main inclined shaft lifting, open pit mine and ground transportation system. It is an ideal supporting equipment for coal mining mechanization with -10℃~+40℃working environment.
Electric-generation Principle
The downwards transportation belt conveyor is to transport the materials from high to low. At this time, the conveyor only needs to overcome the friction, so its load is very light. If the component of gravity of the transported material in the running direction is greater than the frictional force of the belt conveyor itself, the rotor of the motor will be passively accelerated under the drag of the materials. When the motor speed exceeds its own synchronous speed, the motor will give out the electric power and the braking force is generated to limit motor speed to rise, that is, the potential energy of the material falling is converted into electric energy by the motor. Therefore, the electric energy emitted from the material being transported can be re-categorized into the grid through a series of means.
Technological Difficulty
The downwards transportation belt conveyor is a special conveyor that transports materials from high to low. It has negative power during transportation of materials, and the motor is in the state of power generation braking. It can effectively control the full-load start and stop of the belt conveyor, especially the controllable soft brake of the belt conveyor can be realized under the condition of sudden power loss. Preventing the belt conveyor from running way is the key technology of the downward belt conveyor.
Solution
1. Adopting power generation operation mode the conveyor runs in the “zero power loss” state, and the excess power can also be used by other equipment.
2. Through the signal acquisition logic design, the system can not lose the logic design of the whole system after the cable is interrupted.
3. Adopting protection device design, a test network for the entire downward belt conveyor monitoring is built by a simple electrical switch.
4. The logic control of the emergency brake lock system ensures the safety and reliability of the conveyor under a large angle and high risk.
5. Long-distance signal stable acquisition anti-interference circuit design makes the transmission of long-distance acquisition signal reliable and fidelity.
