CN107697598A - A kind of frequency conversion drag conveyor Intelligent speed-adjustable control system - Google Patents

Abstract

The invention relates to speed regulation control of a scraper conveyor adopting frequency conversion control in underground coal mines. Specifically, the running speed of the scraper conveyor is changed by adjusting the output frequency of the frequency converter to achieve the effect of saving energy and reducing consumption. The system consists of a centralized control center, a frequency converter for the head of the scraper conveyor, a frequency converter for the tail of the scraper conveyor, and a frequency converter for the transfer machine. The centralized control center adjusts the operation of each frequency converter in real time by collecting the operating current of each frequency converter frequency to realize the intelligent speed regulation of the scraper conveyor; when the loader is empty, reduce the running speed of the scraper; When the reloader is heavily loaded, reduce the running speed of the scraper and reduce the coal loading of the reloader. Through the intelligent speed regulation of the scraper conveyor, the wear and tear of the equipment can be reduced and the service life of the equipment can be improved without affecting the output, so as to achieve the effect of energy saving and consumption reduction by applying frequency conversion technology in underground coal mines.

Description

An Intelligent Speed Regulation Control System for Frequency Conversion Scraper Conveyor

technical field

The invention relates to intelligent speed regulation control of a scraper conveyor controlled by a frequency converter in underground coal mines, specifically a control system for changing the running speed of a scraper conveyor by intelligently adjusting the output frequency of the frequency converter.

Background technique

In coal mine fully mechanized mining equipment, the scraper conveyor transports the coal mined by the shearer to the transfer machine, and the transfer machine transfers it to the belt conveyor and then transports it to the ground. In the traditional way, the motor of the scraper machine is a single-speed motor or a double-speed motor. After the scraper machine is started, the motor keeps working at the power frequency. The speed and torque of the motor can only be self-adapted by the characteristic curve of the motor itself. Adjustment, the motor speed cannot be adjusted independently, resulting in a small load on the scraper machine or no load on the scraper machine, the motor still maintains high-speed operation, resulting in a large amount of power loss and increased wear and tear on the equipment. With the continuous development of power electronics technology, frequency conversion technology has been widely used in all walks of life in my country. Using frequency conversion speed regulation technology, the frequency converter can freely adjust the power supply frequency of the motor and operate at a frequency lower than 50Hz. In various control modes Under the guarantee of the motor, the low-speed start and operation of the motor can be realized. In practical applications, if the running speed of the scraper machine can be intelligently adjusted by detecting the amount of coal transported by the scraper machine, it can save energy and reduce consumption, and reduce the wear and tear of the equipment. The service life of the equipment is shortened. Due to the harsh and complex site conditions of the fully mechanized mining face, and the roof support of the scraper machine is constantly rising and falling during the coal mining process, there is no ideal method to detect the actual coal volume on the scraper machine. The coal flow sensor is used for detection, and the actual error is relatively large, and the application effect is poor. As the next-level transportation equipment of the scraper conveyor, the loader drives its motor. The working current of its motor is related to its load, which is not only the amount of coal transported, but also related to the current load of the scraper conveyor. Therefore, the scraper can be adjusted by the working current of the loader motor. The running speed of the trigger machine reaches the goal of intelligent debugging of the scraper machine.

Contents of the invention

The purpose of the present invention is to realize the intelligence of the scraper conveyor in the fully mechanized mining face through the method of fuzzy control when the scraper conveyor and the reloader in the coal mine are driven by a frequency converter. Debugging, improve the service life of the equipment and achieve the purpose of saving energy and reducing consumption without affecting the coal mining process.

The present invention is an intelligent debugging control system for variable frequency scraper conveyor in coal mine, which includes a centralized control center, a frequency converter for a reloading machine, a frequency converter for the head of a scraper machine, and a frequency converter for a tail of a scraper machine. The operating current of each frequency converter, and can adjust the operating frequency of each frequency converter in real time. When the frequency converter of the scraper machine and the reloader start to the rated operating frequency, the centralized control center will adjust the frequency converter of the scraper machine according to the operating current of the reloader. Speed control methods, including no-load low-speed control of the scraper machine, speed-up control of the scraper machine, and speed-down control of the scraper machine:

Low-speed control of the scraper machine: When the running current of the loader continues to run at no-load current, control the frequency converter of the scraper machine to maintain the operation at the no-load frequency until the current of the loader is greater than the no-load current to perform other speed regulation control processes;

Speed up control of the scraper machine: When the running current of the loader is greater than the no-load current and lower than the lower limit current, control the inverter of the scraper machine to increase the frequency to run until the running current of the loader is greater than the normal working current, stop increasing the frequency, and control The frequency converter of the scraper machine maintains the current frequency operation;

Speed reduction control of the scraper machine: When the running current of the scraper machine exceeds the upper limit current, control the inverter of the scraper machine to reduce the frequency to run until the running current of the scraper machine is lower than the normal working current, stop reducing the frequency, and control the inverter of the scraper machine to maintain the current current frequency operation.

The beneficial effect of the patent of the present invention is: in the case of additionally installing a coal quantity test sensor, the fuzzy control method is adopted, and the intelligent debugging of the scraper conveyor is realized according to the operating current of the reloading machine through the centralized control center, which not only simplifies the intelligent speed regulation The configuration of the system improves the reliability of the system, improves the efficiency of the equipment, and reduces the wear and tear of the equipment and the waste of energy.

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings:

Figure 1 System composition diagram

Figure 2 Speed control flow chart

detailed description:

As shown in Figure 1, the system includes a centralized control center, a reloading machine inverter, a scraper head inverter, and a scraper tail inverter. Real-time data communication is performed between the centralized control center and each inverter, and the centralized control The center can collect the operating data of each inverter, including the operating current. The centralized control center can control the operating frequency of each inverter, and control the frequency increase and decrease. For communication, the centralized control center controls it as a piece of equipment, and the centralized control center has centralized display, control process parameter setting and manual and automatic control functions.

According to different site conditions, fully mechanized mining face matching and installed capacity, system parameters related to intelligent speed regulation need to be preset in the centralized control center, including:

Loader no-load current: the running current of the motor when the loader is in the no-load state;

Loader lower limit current: the working current when the loader is in the state of coal transportation and the transportation volume is seriously insufficient;

Loader upper limit current: the working current when the loader reaches the overload state or the current coal volume reaches the limit capacity of the belt conveyor;

The normal current of the loader: the working current when the transport volume of the loader reaches the ideal state;

No-load frequency of the scraper machine: the operating frequency set when the scraper machine is no-load, which not only reduces the wear and tear of the equipment, but also reduces the energy consumption of the equipment.

When the reloader and scraper machine reach the rated speed after starting, the speed regulation control process is carried out:

See Figure 2:

(1). The centralized control center monitors the operating current of the reloading machine in real time. When it continues to be less than the set no-load current, it means that the reloading machine and the scraper machine are in the no-load operation state for a long time, and the frequency converter of the scraper machine is controlled to run at the setting fixed no-load frequency.

(2). When the operating current of the reloader is greater than the set upper limit current, it means that the coal volume of the scraper machine is too large. By reducing the operating frequency of the scraper machine inverter to reduce the transport capacity of the reloader, with the operation of the scraper machine As the speed decreases, the amount of coal loaded on the transfer machine decreases, and the operating current of the transfer machine continues to drop. When the current of the transfer machine is lower than the set normal current value, stop reducing the operating speed of the scraper machine and keep it running at the current speed.

(3). When the operating current of the loader is lower than the set lower limit current, it means that the coal volume of the scraper machine is small. Increase the transport capacity of the loader by increasing the operating frequency of the inverter of the scraper machine. When the current of the loader is greater than the set Set the normal current value formula, stop increasing the running speed of the scraper machine, and keep it running at the current speed.

Claims (1)

1. a kind of underground coal mine frequency conversion drag conveyor intelligent regulator control system, including centralized control center, elevating conveyor frequency converter, scrape Trigger head frequency converter, scrapper conveyor tail frequency converter, centralized control center gather the running current of each frequency converter by data communication, And the running frequency of each frequency converter can be adjusted in real time, it is characterised in that when scrapper conveyor, elevating conveyor inverter start up are to specified After running frequency, control method of the centralized control center according to elevating conveyor running current to scrapper conveyor frequency converter timing, including scrapper conveyor Unloaded low speed control, the control of scrapper conveyor rising film condensation, scrapper conveyor reduction of speed：

Scrapper conveyor low speed controls：When elevating conveyor running current continuous service is in no-load current, control scrapper conveyor frequency converter maintains Run in idling frequency, other speed regulating control flows are carried out until elevating conveyor electric current is more than no-load current；

Scrapper conveyor rising film condensation：When elevating conveyor running current is more than no-load current and is less than lower current, control scrapper conveyor becomes The rise frequency operation of frequency device, top out frequency when elevating conveyor running current is more than running current, and controls scraper plate Machine frequency converter maintains current frequency operation；

Scrapper conveyor reduction of speed controls：When elevating conveyor running current exceedes upper limit current, control scrapper conveyor frequency converter reduces frequency fortune OK, stop reducing frequency when elevating conveyor running current is less than running current, and control scrapper conveyor frequency converter to maintain to work as Preceding frequency operation；

Wherein：Elevating conveyor no-load current：Elevating conveyor is in the running current of motor under Light Condition；

Elevating conveyor lower current：Elevating conveyor is under transporting coal state, the operating current in the case of freight volume wretched insufficiency；

Elevating conveyor upper limit current：Work electricity when elevating conveyor reaches overload or current coal amount reaches belt feeder limit freight volume Stream；

Elevating conveyor normal current：Elevating conveyor freight volume reaches operating current ideally.