Hoist frequency control system mainly by the inverter, stroke control, operation control, energy consumption brake and brake brake and other components. The stroke control is mainly carried out on the Hoist and lowering of the hoisting machine. The stroke control mainly carries on the precise stroke control to the Hoist, stopping and braking of the hoist. The operation control mainly completes the Hoist, starting, Emergency braking and other operational control; energy consumption brake and brake brake to achieve the main elevator control.
The stroke control is controlled according to the lifting position (stroke range) of the hoist. The stroke controller converts the stroke position into a switching signal, and performs multi-speed variable frequency control, parking control and brake control through the control terminal of the inverter. Stroke control can be a good way to prevent the hoist over the roll, over discharge, derailment and rollover and other accidents, especially for the corners and fork in the special inclined shaft.
The operation control mainly performs the control of the hoist starting, falling start and emergency brake brake. The "lifting start" operation controls the inverter to run normally and the lifting process is controlled by the lifting stroke control of the stroke controller; the "dropping start" operation controls the frequency conversion The reverse braking process is controlled by the descending stroke of the travel controller. The "emergency brake" operation controls the inverter stop and brake brake at the time of abnormality.
Hoist is one of the main equipment of coal mine, the braking system is directly related to whether the safe operation of the hoist. But the current domestic braking system on the braking system of the measurement and the measurement of empty travel time has not yet reached the level of standardization and quantification, the maintenance of the brake system on a regular basis, so there are two problems:
A. Usually can not determine whether the normal working state of the brake, brake torque and empty travel time is within the specified requirements, so inevitably make the brake with hidden work;
B. The existing visual inspection and routine maintenance system can only make the diagnosis and repair of external damage to its parts, and the internal damage and fatigue caused by the parts such as the disc spring of the object brake can not be made in time The diagnosis and repair. The resulting lift accidents have occurred in the country. Therefore, it is necessary to monitor the working status of the elevator system on-line and fault diagnosis to ensure the safe operation of the hoist.