Integrally-moving high-voltage variable-frequency electric control device

Abstract

The invention discloses an integrally-moving high-voltage variable-frequency electric control device, relating to a variable-frequency device. In the device, an exciting surge suppression cabinet, a transformer cabinet, a power cabinet and a control cabinet are arranged in a shell; a vacuum contactor and a current limiting resistor are arranged in the exciting surge suppression cabinet; a rectifying transformer is arranged in the transformer cabinet; a power unit for realizing variable-voltage and variable-frequency output is arranged in the power cabinet; a PLC (Programmable Logic Controller) unit is arranged in the control cabinet; the vacuum contactor and the current limiting resistor are connected with the rectifying transformer; the rectifying transformer is connected with the power unit; the power unit is connected with the PLC unit; the rectifying side of the power unit is used for performing controllable rectification by adopting an IGBT (Insulated Gate Bipolar Transistor) three-phase full bridge; a filtering and energy-storing electrolysis capacitor is connected in parallel in the middle; and an output side is provided with an H-bridge consisting of four IGBTs. The control device has the advantages of convenience and quickness for transporting and installing, and good energy-saving effect.

Description

technical field [0001] The invention relates to a frequency conversion device, in particular to an integral mobile high-voltage frequency conversion electric control device. Background technique [0002] Among the power equipment in the basic construction of the mine, the electric control system of the hoist is composed of multiple parts. The installation and commissioning of the electric control system of the hoist are the most complicated and time-consuming, especially in projects where the owner requires a tight construction schedule. The hoist installation takes up a large part of the preparation time, so how to shorten the electromechanical installation time is a difficult problem that many mechanical and electrical technicians in well construction continue to overcome. [0003] At present, the vast majority of mine hoists in my country adopt the AC speed control system (represented by TKD-A) of winding type asynchronous motor rotor series resistors for speed regulation...

AI Technical Summary

Problems solved by technology

[0002] Among the power equipment in the basic construction of the mine, the electric control system of the hoist is composed of multiple parts. The installation and commissioning of the electric control system of the hoist are the most complicated and time-consuming, especially in projects where the owner requires a tight construction schedule. The hoist installation takes up a large part of the preparation time, so how to shorten the electromechanical installation time is a difficult problem that many mechanical and electrical technicians in well construction continue to overcome

[0003] At present, the vast majority of mine hoists in my country adopt the AC speed control system (represented by TKD-A) of winding type asynchronous motor rotor series resistors for speed regulation. These hoists are all products from the 1960s to the 1970s. The following problems: low power factor of the system, large impact of starting current and switching current, unstable operation of equipment, easy to cause electrical and mechanical shock; complex control circuit, poor working stability and reliability, lack of fault diagnosis function, difficult to troubleshoot; rotor circuit Metal resistors are connected in series, which consumes electric energy and causes energy waste, and the serious heat generation deteriorates the working environment; the poor contact of the motor slip ring easily causes equipment failure, and the maintenance workload and cost are high; in addition, the electrical control part of the system adopts a plate structure, and the Large, high operating noise, and all terminal posts are exposed, causing great harm to operating safety

[0007] During the acceleration process above medium speed, the motor current decreases, about 1-1.7 times the rated current, the output torque of the motor also decreases, about 1-1.7 times the rated torque, and the pulsation increases, the output torque before and after the switch action There is a large jump, and the power consumed by the motor has decreased, but because the acceleration torque is low and the acceleration time is long, the actual power consumption during the acceleration process has not decreased

Due to the low acceleration torque, this control method is not suitable for heavy lifting applications

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