Motor relay protection device and method for belt conveyor scratch fault protection

Abstract

The invention discloses a motor relay protection device and method for belt conveyor scratch fault protection, and the device comprises an AC value collection unit, a switching value input unit, a switching value output unit, a processing unit, and a current transformer, and the current transformer is used for being installed on a connection wire between a power bus and a motor. The alternating current quantity acquisition unit, the switching value input unit and the switching value output unit are connected with the processing unit, the alternating current quantity acquisition unit is connected with the current transformer, a receiving end of the switching value input unit is connected with the circuit breaker, and a transmitting end of the switching value output unit is connected with the circuit breaker. The device can detect the belt scratch fault in real time, gives an alarm in time or automatically trips to prevent an accident from being serialized, effectively reduces the scratch fault rate of the belt conveyor, and improves the economic benefits of a power plant.

Description

technical field [0001] The invention belongs to the technical field of power system relay protection, and can realize the functions of early warning and protection tripping for scratching faults of belt conveyors in power plants in a motor relay protection device. Background technique [0002] Belt conveyor, commonly known as belt conveyor, is an important transportation equipment for coal conveying systems in thermal power plants. It is driven by a motor, and then forms a closed-loop belt that rotates at a uniform speed through tensioning, redirecting and other components, and drives the belt with static friction. The object moves at a uniform speed with it, so as to achieve the purpose of conveying materials. The belt accounts for more than 40% of the cost of the entire conveyor, and it is a weak link that is easily damaged. Therefore, protecting the monitoring belt to minimize damage is of great significance to maintaining the safe operation of the power plant. The belt ...

AI Technical Summary

Problems solved by technology

For example, when the belt is scratched by an instantaneous sharp object, the current suddenly increases for a short time, but the current amplitude and duration may not reach the threshold of the overcurrent and overload protection setting, and the protection will not operate; or there is a foreign object stuck on the belt. At this time, the motor is still rotating without blocking, and the blocking protection will not operate; or when the belt is scratched, although the current rises, there is less material on the belt, and the current is close to or lower than the rated value of the motor. Current, the conventional protection logic will not start at this time, and it is easy to damage the belt if it continues to run for a long time

Images