A blast furnace hoist control system with automatic encoder switching and its switching method

Abstract

The present invention discloses a blast furnace hoist control system with automatic encoder switching and its switching method. The system includes a hoist control system and a switching control system. The hoist control system includes: motor one, encoder one, encoder two, motor two, frequency converter one, frequency converter two, frequency converter three, and hoist control equipment. The switching control system includes: a touch screen, a switching controller, and a relay group. The touch screen is connected to the switching controller. The switching controller is electrically connected to the control coils of each relay in the relay group. This system improves the stability and reliability of the blast furnace hoist control system, greatly reduces the failure rate caused by the encoder, facilitates the quick confirmation and repair of the fault point, and reduces the operation and maintenance time cost of the enterprise.

Description

Technical Field

[0001] The present invention relates to the technical field of hoist control, and particularly to a blast furnace hoist control system with automatic encoder switching and a switching method thereof. Background Art

[0002] The charging form of a blast furnace mainly includes charging by a hoist trolley and charging by a conveyor belt. Among them, the main working process of the hoist trolley charging equipment is that various raw materials are put into a centralized hopper through batching under the trough. After the skip reaches the pit, the door of the centralized hopper automatically opens, and the raw materials are put into the skip. When the gate of the centralized hopper is closed in place, the skip starts, accelerates, moves at a constant speed, decelerates, stops at the top of the furnace, and then uses a discharge curved rail to lift the rear wheels of the trolley and automatically tilt it to a certain angle for discharging. After discharging, the trolley returns. During the working process, two skips alternate in charging. When the skip full of furnace charge moves upward, the empty skip moves downward; the hoist trolley charging equipment has a compact structure and a small floor area, and can achieve automatic and semi-automatic control when ensuring and meeting the charging capacity. In the prior art, the drive control method of the hoist trolley is to directly start the forward and reverse rotation of a hoist by simultaneously controlling two asynchronous motors. The two asynchronous motors are cooperatively controlled by two frequency converters (one main and one slave) and related hoist control equipment to complete charging, and the frequency converters communicate with each other through optical fibers. The speed of the motor is fed back to the frequency converter through an encoder. This system has a complex circuit and a cumbersome switching process. If the encoder fails, it is impossible to continue controlling the hoist motor for charging, and it is also not convenient for maintenance personnel to check and maintain. Summary of the Invention

[0003] Aiming at the problems in the prior art, the present invention provides a blast furnace hoist control system with automatic encoder switching and a switching method thereof. The system improves the stability and reliability of the blast furnace hoist control system, automatically switches in case of a fault, greatly reduces the failure rate caused by the encoder, and facilitates the quick confirmation and repair of the fault point.

[0004] To achieve the object of the present invention, the present invention adopts the following technical solutions:

[0005] A blast furnace hoist control system with automatic encoder switching includes a hoist control system and a switching control system; the hoist control system includes: motor one, encoder one, encoder two, motor two, frequency converter one, frequency converter two, frequency converter three, and hoist control equipment; encoder one is installed on motor one, and encoder two is installed on motor two; frequency converter one and frequency converter two are respectively electrically connected to motor one through contactor KM1 and contactor KM2; frequency converter two and frequency converter three are respectively electrically connected to motor two through contactor KM3 and contactor KM4; the control ends of contactors KM1, KM2, KM3, and KM4 are connected to the hoist control equipment;

[0006] The described switching control system includes: a touch screen, a switching controller, and a relay group; the touch screen is connected to the switching controller; the switching controller is electrically connected to the control coils of the relays in the relay group; the contacts of the relays in the relay group are respectively electrically connected to frequency converter one, frequency converter two, frequency converter three, encoder one, and encoder two; by controlling the states of the individual relays in the relay group through the switching controller, the output terminals of encoder one and encoder two are respectively switched to two of frequency converter one, frequency converter two, and frequency converter three, or the output terminal of encoder one is switched to two of frequency converter one, frequency converter two, and frequency converter three, or the output terminal of encoder two is switched to two of frequency converter one, frequency converter two, and frequency converter three.

[0007] The output terminals of the described encoder one and encoder two are electrically connected to the switching controller.

[0008] The control terminals of the described contactors KM1, KM2, KM3, and KM4 are respectively connected in parallel with relays KA11, KA12, KA13, and KA14; the relays KA11, KA12, KA13, and KA14 are electrically connected to the switching controller;

[0009] A switching switch with three states of automatic, manual, or unselected and an indicator light that lights up when frequency converter two is the main unit are connected to the described switching controller;

[0010] Preferably, the relay group includes KA1, KA2, KA3, KA4, KA5, KA6, KA7, KA8, KA9, and KA10; encoder one is electrically connected to frequency converter one through the normally closed contacts of KA1, KA2, and KA3; encoder two is electrically connected to frequency converter three through the normally closed contacts of KA5, KA6, and KA7; the normally open contacts of KA1, KA2, and KA3 are respectively electrically connected to the normally open contacts of KA5, KA6, and KA7; the normally open contacts of KA1, KA2, KA5, and KA6 are electrically connected to frequency converter two; the normally open contacts of KA3 and KA7 are respectively electrically connected to the normally open contacts of KA4 and KA8; the normally closed contacts of KA4 are electrically connected to the normally closed contacts of KA8; the normally open contacts of KA4 and KA8 are respectively electrically connected to KA9 and KA10; the normally open contacts of KA9 and KA10 and frequency converter two are electrically connected; the normally closed contact of KA9 is electrically connected to frequency converter three; the normally closed contact of KA10 is electrically connected to frequency converter one.

[0011] Preferably, one path of the switching signal output by the switching controller is connected to the input terminal of the winch control device.

[0012] Preferably, the switching controller includes a main PLC and a slave PLC; an output terminal of the main PLC is electrically connected to an input terminal of the slave PLC; the signal input to the switching controller is simultaneously connected to the input terminals of the main PLC and the slave PLC, and the signal output from the switching controller is simultaneously connected to the output terminals of the main PLC and the slave PLC.

[0013] Preferably, a switching method for an encoder automatic switching blast furnace hoist control system is completed through operations on a touch screen and a changeover switch; wherein, a main interface and a control display interface are provided on the touch screen;

[0014] The method includes the following steps:

[0015] First, control the changeover switch according to the switching state of the second frequency converter in the current hoist control system;

[0016] The switch has the following states:

[0017] Automatic: The system automatically determines whether the second frequency converter is the main machine, the slave machine or the standby according to the states of the relays KA11, KA12, KA13, and KA14;

[0018] Manual: Manually directly select that the second frequency converter is the main machine in the current state;

[0019] Not selected: The second frequency converter is not put into operation in the current state and is in standby;

[0020] The touch screen displays the state of the changeover switch and the information on whether the second frequency converter is the main machine on the main interface according to the current state;

[0021] Secondly, click on the main interface of the touch screen to enter the control display interface, and the control display interface displays the switching states of the current encoder and frequency converter, and the state of the main PLC in the form of a schematic diagram and text.

[0022] Preferably, there are a "PLC interface" button and a "Help" button on the control display interface. Click the "PLC interface" button to enter the PLC interface, and the PLC interface displays the current input and output interface states of the main PLC and the slave PLC, as well as the functions of each input and output interface and the position information of the connected devices;

[0023] Click the "Help" button to enter the truth table interface, which displays the relationship between the states of each relay in the relay group and the control of the encoder switching.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This system improves the stability and reliability of the blast furnace hoist control system, greatly reduces the failure rate caused by the encoder, facilitates the quick confirmation and repair of the fault point, reduces the operation and maintenance time cost of the enterprise, is convenient for operation and maintenance, reduces the work of maintenance personnel, and achieves good economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a structural block diagram of a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0027] Figure 2 is a circuit diagram of the switching system in a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0028] Figure 3 is the main interface in the switching method of a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0029] Figure 4 is the control display interface of the switching method of a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0030] Figure 5 is the PLC interface of the switching method of a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0031] Figure 6 is the truth table interface of the switching method of a blast furnace hoist control system with automatic encoder switching according to the present invention;

[0032] In the figure: touch screen 1, switching controller 2, main PLC 201, slave PLC 202, switching switch 203, indicator light 204, hoist control system 3, relay group 4, motor 1 301, encoder 1 302, encoder 2 303, motor 2 304, frequency converter 1 305, frequency converter 2 306, frequency converter 3 307, hoist control equipment 308, main interface 5, control display interface 6, PLC interface 7, truth table interface 8. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention:

[0034] Such as Figure 1-2As shown in the figure, in an embodiment of the present invention, a blast furnace hoist control system with automatic encoder switching includes a hoist control system 3 and a switching control system. The hoist control system 3 includes: a first motor 301, a first encoder 302, a second encoder 303, a second motor 304, a first frequency converter 305, a second frequency converter 306, a third frequency converter 307, and a hoist control device 308. The first encoder 302 is installed on the first motor 301, and the second encoder 303 is installed on the second motor 304. The first frequency converter 305 and the second frequency converter 306 are electrically connected to the first motor 301 through a contactor KM1 and a contactor KM2 respectively. The second frequency converter 306 and the third frequency converter 307 are electrically connected to the second motor 304 through a contactor KM3 and a contactor KM4 respectively. The control terminals of the contactors KM1, KM2, KM3, and KM4 are connected to the hoist control device 308. The hoist control device 308 completes the switching of the first frequency converter 305, the second frequency converter 306, and the third frequency converter 307 through the contactors KM1, KM2, KM3, and KM4. Among them, the first frequency converter 305 only controls the first motor 301 as the main machine. The second frequency converter 306 can be used as both the main machine and the slave machine, and can control both the first motor 301 and the second motor 304. The third frequency converter 307 only controls the second motor 304 as the slave machine, realizing the standby of the second frequency converter 306.

[0035] The switching control system includes: a touch screen 1, a switching controller 2, and a relay group 4. The touch screen 1 is connected to the switching controller 2. The switching controller 2 is electrically connected to the control coils of each relay in the relay group 4. The contacts of each relay in the relay group 4 are respectively connected to the first frequency converter 305, the second frequency converter 306, the third frequency converter 307, the first encoder 302, and the second encoder 303. By controlling the states of the respective relays in the relay group 4 through the switching controller 2, the output terminals of the first encoder 302 and the second encoder 303 are respectively switched to two of the first frequency converter 305, the second frequency converter 306, and the third frequency converter, or the output terminal of the first encoder 302 is switched to two of the first frequency converter 305, the second frequency converter 306, and the third frequency converter, or the output terminal of the second encoder 303 is switched to two of the first frequency converter 305, the second frequency converter 306, and the third frequency converter. In this way, the switching of the two encoders on the three frequency converters is realized, facilitating the switching during machine changeover and maintenance.

[0036] The output terminals of the first encoder 302 and the second encoder 303 are electrically connected to the switching controller 2, and the switching controller 2 can determine whether the outputs of the first encoder 302 and the second encoder 303 are faulty.

[0037] The control terminals of the contactors KM1, KM2, KM3, and KM4 are respectively connected in parallel with the relays KA11, KA12, KA13, and KA14; the relays KA11, KA12, KA13, and KA14 are electrically connected to the switching controller 2; by collecting the states of the relays KA11, KA12, KA13, and KA14 through the switching controller 2, the switching states of the current frequency converters 1 - 305, 2 - 306, and 3 - 307 are obtained.

[0038] A change - over switch 203 with three states of automatic, manual, or not selected and an indicator light 204 that lights up when the frequency converter 2 - 306 is the main unit are connected to the switching controller 2;

[0039] Automatic: The system automatically determines whether the frequency converter 2 - 306 is the main unit, a slave unit, or a standby according to the states of the relays KA11, KA12, KA13, and KA14;

[0040] Manual: Manually directly select that the frequency converter 2 - 306 is the main unit in the current state;

[0041] Not selected: The current frequency converter 2 - 306 is not put into use and is in standby;

[0042] Specifically, the relay group 4 includes KA1, KA2, KA3, KA4, KA5, KA6, KA7, KA8, KA9, and KA10; the encoder 1 - 302 is electrically connected to the frequency converter 1 - 305 through the normally - closed contacts of KA1, KA2, and KA3; the encoder 2 - 303 is electrically connected to the frequency converter 3 - 307 through the normally - closed contacts of KA5, KA6, and KA7; the normally - open contacts of KA1, KA2, and KA3 are respectively electrically connected to the normally - open contacts of KA5, KA6, and KA7; the normally - open contacts of KA1, KA2, KA5, and KA6 are electrically connected to the frequency converter 2 - 306; the normally - open contacts of KA3 and KA7 are respectively electrically connected to the normally - open contacts of KA4 and KA8; the normally - closed contacts of KA4 and KA8 are electrically connected; the normally - open contacts of KA4 and KA8 are respectively electrically connected to KA9 and KA10; the normally - open contacts of KA9 and KA10 and the frequency converter 2 - 306 are electrically connected; the normally - closed contact of KA9 is electrically connected to the frequency converter 3 - 307; the normally - closed contact of KA10 is electrically connected to the frequency converter 1 - 305.

[0043] The truth table for controlling the encoder switching in the above connection method is shown in Table 1 below, where Z11: frequency converter 1 - 305; Z12: frequency converter 2 - 306; Z13: frequency converter 3 - 307; ON indicates that the relay is closed;

[0044] Table 1 Relay Group Truth Table

[0045]

[0046] In a specific embodiment of the present invention, an output switching signal of the switching controller 2 is connected to an input end of the hoist control device 308; when the changeover switch 203 is in the automatic state, an initial control signal is given to the hoist control device 308, taking the frequency converter two 306 as the main machine and cutting out the frequency converter one 305 for standby.

[0047] In a specific embodiment of the present invention, the switching controller 2 includes a main PLC 201 and a slave PLC 202; an output end of the main PLC 201 is electrically connected to an input end of the slave PLC 202; used to judge whether the main PLC 201 is operating normally; the signals input to the switching controller 2 are simultaneously connected to the input ends of the main PLC 201 and the slave PLC 202, and the signals output from the switching controller 2 are simultaneously connected to the output ends of the main PLC 201 and the slave PLC 202.

[0048] As Figure 3-6 shown, a switching method for a hoist control system of a blast furnace with automatic encoder switching includes:

[0049] It is completed through operations on the touch screen 1 and the changeover switch 203;

[0050] Among them, a main interface 5 and a control display interface 6 are set on the touch screen 1;

[0051] First, control the changeover switch 203 according to the switching state of the frequency converter two 306 in the current hoist control system 3;

[0052] The switch has the following states:

[0053] Automatic: The system automatically determines whether the frequency converter two 306 is the main machine, a slave machine or in standby according to the states of the relays KA11, KA12, KA13, and KA14;

[0054] Manual: Manually directly select that the frequency converter two 306 is the main machine in the current state;

[0055] Not selected: The frequency converter two 306 is not put into operation in the current state and is in standby;

[0056] The touch screen 1 displays the state of the changeover switch 203 and the information on whether the frequency converter two 306 is the main machine on the main interface according to the current state;

[0057] Secondly, click on the main interface 5 of the touch screen 1 to enter the control display interface 6. The control display interface 6 displays the switching states of the current encoder and frequency converter and the state of the main PLC in the form of schematic diagrams and text; providing an intuitive control state for users to facilitate encoder fault confirmation and maintenance and repair.

[0058] Specifically, there are a "PLC Interface" button and a "Help" button on the control display interface 6. Clicking the "PLC Interface" button enters the PLC interface 7, which displays the current input / output interface status of the main PLC 201 and the slave PLC 202, as well as the functions of each input / output interface and the location information of the connected devices, enabling the operator to quickly locate faults for repair;

[0059] Clicking the "Help" button enters the truth table interface 8, which displays the relationship between the status of each relay in the relay group and the control encoder switching (as shown in Table 1); facilitating the operator's understanding and fault repair.

[0060] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its improved concept, making equivalent substitutions or changes, should be covered by the protection scope of the present invention.

Claims

1. A blast furnace hoist control system with automatic encoder switching, comprising a hoist control system and a switching control system; the hoist control system includes: Motor 1, Encoder 1, Encoder 2, Motor 2, Frequency Converter 1, Frequency Converter 2, Frequency Converter 3, Hoist Control Equipment; Encoder 1 is installed on Motor 1, and Encoder 2 is installed on Motor 2; Frequency Converter 1 and Frequency Converter 2 are electrically connected to Motor 1 through Contactor KM1 and Contactor KM2 respectively; Frequency Converter 2 and Frequency Converter 3 are electrically connected to Motor 2 through Contactor KM3 and Contactor KM4 respectively; the control terminals of Contactor KM1, KM2, KM3, and KM4 are connected to the Hoist Control Equipment; The described switching control system includes: a touch screen, a switching controller, and a relay group; the touch screen is connected to the switching controller; the switching controller is electrically connected to the control coils of each relay in the relay group; the contacts of each relay in the relay group are respectively connected to Frequency Converter 1, Frequency Converter 2, Frequency Converter 3, Encoder 1, and Encoder 2; by controlling the states of each relay in the relay group through the switching controller, the output terminals of Encoder 1 and Encoder 2 are respectively switched to two of Frequency Converter 1, Frequency Converter 2, and Frequency Converter 3, or the output terminal of Encoder 1 is switched to two of Frequency Converter 1, Frequency Converter 2, and Frequency Converter 3, or the output terminal of Encoder 2 is switched to two of Frequency Converter 1, Frequency Converter 2, and Frequency Converter 3; The output terminals of the described Encoder 1 and Encoder 2 are connected to the switching controller. The control terminals of the described Contactor KM1, KM2, KM3, and KM4 are respectively connected in parallel with Relay KA11, KA12, KA13, and KA14; the Relay KA11, KA12, KA13, and KA14 are connected to the switching controller. A switching switch with three states of automatic, manual, or not selected and an indicator light that lights up when Frequency Converter 2 is the main unit are connected to the switching controller. Among them, the described switching controller includes a main PLC and a slave PLC; an output terminal of the main PLC is electrically connected to an input terminal of the slave PLC; the signals input to the switching controller are simultaneously connected to the input terminals of the main PLC and the slave PLC, and the signals output from the slave switching controller are simultaneously connected to the output terminals of the main PLC and the slave PLC; Among them, the relay group includes KA1, KA2, KA3, KA4, KA5, KA6, KA7, KA8, KA9, and KA10; Encoder 1 is electrically connected to Inverter 1 through the normally closed contacts of KA1, KA2, and KA3; Encoder 2 is electrically connected to Inverter 3 through the normally closed contacts of KA5, KA6, and KA7; The normally open contacts of KA1, KA2, and KA3 are respectively electrically connected to the normally open contacts of KA5, KA6, and KA7; The normally open contacts of KA1, KA2, KA5, and KA6 are electrically connected to Inverter 2; The normally open contacts of KA3 and KA7 are respectively electrically connected to the normally open contacts of KA4 and KA8; The normally closed contact of KA4 is electrically connected to the normally closed contact of KA8; The normally open contacts of KA4 and KA8 are respectively electrically connected to KA9 and KA10; The normally open contacts of KA9 and KA10 and Inverter 2 are electrically connected; The normally closed contact of KA9 is electrically connected to Inverter 3; The normally closed contact of KA10 is electrically connected to Inverter 1.

2. The blast furnace hoist control system with automatic encoder switching according to claim 1, characterized in that: One path of the switching signal output by the switching controller is connected to the input end of the winch control device.

3. The switching method of the blast furnace hoist control system with automatic encoder switching according to claim 2 is completed by operating the touch screen and the switching switch; wherein, The touch screen is provided with a main interface and a control display interface; It is characterized in that: The following steps are included: First, control the switching switch according to the switching state of Inverter 2 in the current winch control system; The switch has the following states: Automatic: The system automatically determines whether Inverter 2 is the main machine, a slave machine, or a standby according to the states of relays KA11, KA12, KA13, and KA14. Manual: Manually directly select that Inverter 2 is the main machine in the current state. Not selected; Inverter 2 is not put into operation in the current state and is in standby. The touch screen displays the state of the switching switch and the information on whether Inverter 2 is the main machine on the main interface according to the current state. Secondly, click the main interface of the touch screen to enter the control display interface. The control display interface displays the switching states of the current encoder and inverter and the state of the main PLC in the form of a schematic diagram and text.

4. The switching method of the blast furnace hoist control system with automatic encoder switching according to claim 3, characterized in that: There are "PLC Interface" button and "Help" button on the control display interface. Click the "PLC Interface" button to enter the PLC interface. The PLC interface displays the current input and output interface states of the main PLC and the slave PLC, as well as the functions of each input and output interface and the position information of the connected devices. Click the "Help" button to enter the truth table interface, which displays the relationship between the states of each relay in the relay group and the control encoder switching.

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