The full-digital DC electrical control system can be used in combination with single-rope and multi-rope DC hoist in coal and non-ferrous metal mines, including the main and auxiliary shaft hoists and sinking hoist, or with cross-dam hoist and ship lift. Operation, control and drive of the hoist are based on advanced computer control technologies. It can not only be used with hoist newly installed, but also applicable for technical modification of the generator set control devices and analog DC electrical control equipments of hoist.

The drive part is mainly composed of full-digital speed regulator and thyristor rectifying device, which is provided with two modes of configuration:

▓ Simens or ABB elements imported in original packaging;

▓ Imported small-size Simens or ABB full-digital speed regulation, fitted with domestic thyristor power unit;

▓ 6 pulse;

▓ 12 pulse (12 pulse in series, 12 pulse in parallel)

▓ Magnet field reversible (power) ＞1500KW, armature reversible (power≤1500KW);

▓ Overvoltage and overcurrent protection of the main circuit;

▓ Fault protection of the cooling fan;

▓ Open-phase protection of main circuit ground and thyristor;

▓ Undercurrent and overcurrent protection of excitation;

▓ Fault protection of speed feedback;

▓ Manual, semi-automatic and full-automatic speed setting control;

▓ Anti-shock curve control of S-start;

▓Double closed-loop control of speed and current;

▓ Menu-based setting, display and adjustment of parameters;

▓ Amplitude limit of torque and current;

▓ Pre-control of current regulating circuit according to set value of current, counter-emf of motor, current continuity/interruption to improve dynamic performance of the system;

▓ Automatic optimization of parameters of current regulator and speed regulator;

▓ Self diagnosis and alarm of faults;

▓ Sequential control of 12 pulse in series to reduce reactive impact and power;

The operation control system composed of Simens (or GE) PLC, is featured as follows:

▓ Maintenance, rope test, manual, semi-automatic and full-automatic modes of operation;

▓ Maximum speed limit according to the type of hoisting;

▓ Necessary locks for control of the hoist process;

▓ Two redundant sets of PLC control software and external hardware for the safety circuit to ensure low-speed operation of hoist (emergency driving) in case of PLC failure;

▓ Constant deceleration control of the safety brake process to avoid impact of hoisting, lowering and load, remain constant within the setting range and below the skid deceleration limit, and ensure safe operation of hoist (if the hydraulic system of constant deceleration is provided);

▓ Closed-loop control of hoist position to ensure accurate parking;

▓ Perfect protections against over-speed, pulleying, wire rope slip, shoe wear, spring fatigue, over-current, over-voltage, and converter fault; and important protections are provided doubly or triply to ensure safe operation of hoist;

▓ Mutual monitoring and backup between tachometers and between tachometer and encoder to ensure safe and correct indication and control of speed and depth;

▓ Reasonable and automatic coordination of brake oil pressure and current in the starting process to enable soft start of hoist and avoid starting current impact or hoisting container falling;

The monitoring system is designed with the popular industrial computer as the upper computer, color display and printer, as well as programming and monitoring software. During installation and debugging, it can communicate with the programmable controller for programming in the upper machine, thus saving the cost of a dedicated programmer; the upper computer for monitoring and alarming of the hoist system, is designed with multiple groups of color graphic displays, and available for printing and output at any time. Main functions:

▓ Display and recording of minor fault signals;

▓ Diagnosis, alarm and pre-alarm of major faults;

▓ Multi-hoisting cycle recording of such key parameters as speed, current and oil pressure with depth and time as the coordinates;

▓ Back-up protections (back-up deceleration, pulleying, over-speed, fixed-point inspection and wrong-way);

▓ Real-time display of depth, speed, pressure, current and other parameters;

▓ Functioning memory and display of shaft switch and monitor (depth indicator) limit switch;

▓ Functioning display of various parts of the main shaft handling equipment;

▓ Monitoring over main processes of main machine and electrical control equipments;

▓ Reporting, display and recording of production status and equipment operation;