A frequency converter switching control system based on steel inlet and outlet cantilever rollers

Abstract

The present invention relates to the technical field of control systems, and discloses a frequency converter switching control system based on in-and-out steel cantilever rollers, the system comprising: a collection module: used to collect the operating status of the steel cantilever roller body; a construction module: used to process and analyze the operating status of the steel cantilever roller body, and establish a cantilever roller motion prediction model; a determination module: used to pre-set the accident level, and set a coping method that meets the accident level according to the cantilever roller motion prediction model; an execution module: used to switch the frequency converter according to the coping method. Through the setting of four frequency converters, a gradual switching is performed when power switching is performed, and a smooth switching is achieved by gradually adjusting the frequency converter to adjust the motor frequency; through the setting of the second frequency converter and the third frequency converter, when the first or fourth frequency converter fails, the controller will make the second frequency converter or the third frequency converter work alone, and a single frequency converter controls half of the motors to enable steel to be transported, avoiding the problem of stacking.

Description

Technical Field

[0001] The invention relates to the technical field of control systems, and in particular to a frequency converter switching control system based on inlet and outlet steel cantilever rollers. Background Art

[0002] The heating furnace is one of the most important equipment in the steel rolling system, and the conveyor rollers that match the heating furnace are also an indispensable part of the steel rolling process. The steel inlet and outlet cantilever rollers are responsible for loading and delivering the steel billets into and out of the furnace. Due to the harsh environment of the furnace area and the steel billets themselves, accidents frequently occur in the steel inlet and outlet cantilever rollers and their related equipment, which greatly restricts the stable operation of the steel rolling production line.

[0003] On the production line, different process steps may require different conveying speeds. By controlling the switching of the inverters in and out of the steel cantilever rollers, the production rate can be quickly adjusted and adapted to the process requirements. At the same time, during the production process, there may be low loads and high loads. Using the appropriate inverter to match the load can reduce energy consumption and improve energy efficiency. For example, when the load is low, using a lower frequency inverter can reduce energy consumption.

[0004] Therefore, a switching control system for steel inlet and outlet cantilever rollers is proposed, which can solve the problems that the existing steel inlet and outlet cantilever rollers are difficult to change the transmission speed when in use and that production cannot be continued when a frequency converter fails. Summary of the invention

[0005] The technical problem to be solved by the present invention is to solve the problem that it is difficult to change the transmission speed of the existing steel inlet and outlet cantilever rollers when in use and that production cannot be continued when a frequency converter fails.

[0006] In order to solve the above technical problems, the present invention provides a frequency converter switching control system based on an inlet and outlet steel cantilever roller, the system comprising:

[0007] Collection module: used to collect the running status of the steel cantilever roller body;

[0008] Construction module: used for processing and analyzing the operation status of the steel cantilever roller body and establishing a cantilever roller motion prediction model;

[0009] Determination module: used to pre-set the accident level and set the response method that meets the accident level according to the cantilever roller motion prediction model;

[0010] Execution module: used to switch the inverter according to the response method.

[0011] Preferably, the steel cantilever roller body comprises a steel cantilever roller, a frequency converter and a controller, and the steel cantilever roller comprises a plurality of rollers;

[0012] The frequency converter includes a first frequency converter, a second frequency converter, a third frequency converter and a fourth frequency converter, and the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter are controlled by the controller;

[0013] The controller can independently control the opening and closing of the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter.

[0014] Further preferably, the first frequency converter is connected to the motors of all rollers in the cantilever roller and drives all motors;

[0015] The second frequency converter is connected to the motors of half of the rollers in the cantilever roller and drives half of the motors;

[0016] The third frequency converter is connected to the motor of the other half of the rollers in the cantilever roller and drives the other half of the motor;

[0017] The fourth frequency converter is connected to the electrodes of all rollers in the cantilever roller and drives all motors.

[0018] Further preferably, the rated power of the first frequency converter and the fourth frequency converter is greater than the sum of the powers of all motors connected to the first frequency converter and the fourth frequency converter, that is, greater than the sum of the powers of all motors in the cantilever roller, and the rated power of the first frequency converter is less than the rated power of the fourth frequency converter;

[0019] The rated power of the second inverter and the third inverter is greater than the total power of all motors connected to the second inverter and the third inverter, that is, greater than the total power of half of the motors in the cantilever roller, and the rated power of the second inverter is the same as the rated power of the third inverter, the sum of the rated power of the second inverter and the rated power of the third inverter is greater than the rated power of the first inverter, and the sum of the rated power of the second inverter and the rated power of the third inverter is less than the rated power of the fourth inverter.

[0020] Preferably, the building blocks are specifically used for:

[0021] The building module is used to collect real-time speed and load data of the cantilever roller and pre-process the data;

[0022] The building module is used to analyze the real-time speed and load of the cantilever roller, and to establish a motion prediction model of the cantilever roller according to the real-time speed and load.

[0023] Preferably, the determination module is specifically used for:

[0024] The determination module is used to preset a first accident level for a frequency converter switching accident caused by a cantilever roller failure or maintenance;

[0025] The determination module is used to preset a second accident level for the frequency converter switching accident caused by non-fault or maintenance of the cantilever roller.

[0026] Preferably, the determination module is specifically used for:

[0027] The determination module is used to determine that the frequency converter in use is faulty when the accident level is the first accident level, and preset switching to the second frequency converter or the third frequency converter as the first response method;

[0028] The determination module is used to determine that the inverter needs to adjust power when the accident level is the second accident level, and preset switching to the second inverter and the third inverter to output together as the second coping method.

[0029] Preferably, in the determination module, the first coping method further includes:

[0030] An alarm is issued for the faulty inverter, and the controller controls the faulty inverter to not restart.

[0031] Compared with the prior art, the inverter switching control system based on the steel cantilever roller in and out provided by the embodiment of the present invention has the following beneficial effects:

[0032] Through the setting of four frequency converters, gradual switching is performed when power switching is performed, and the motor frequency is gradually adjusted by gradually adjusting the frequency converter to achieve smooth switching;

[0033] Through the setting of the second and third frequency converters, when the first or fourth frequency converter fails, the controller will make the second or third frequency converter work alone, driving half of the motors of the cantilever roller to work alone, so as to avoid the pile-up problem caused by the acceleration of the front-end steel running speed due to the substantial increase in power without affecting the working efficiency. The single frequency converter controlling half of the motors can also make the steel be transported, avoiding the pile-up problem of the rear-end steel.

[0034] The controller prevents the faulty inverter from restarting, thereby avoiding possible injuries or other engineering accidents caused by the restart of the faulty inverter during the maintenance process. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0036] Figure 1It is a schematic diagram of a frequency converter switching control system based on an inlet and outlet steel cantilever roller provided by an embodiment of the present invention;

[0037] Figure 2 It is a schematic diagram of the connection method between the cantilever roller and the frequency converter provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0039] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0041] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] At present, the heating furnace is one of the most important equipment in the steel rolling system, and the conveyor roller matched with the heating furnace is also an indispensable part of the steel rolling process. The steel inlet and outlet cantilever roller is responsible for loading and sending the steel billet into and out of the furnace. Due to the harsh environment of the furnace area and the steel billet itself and many other factors, accidents of the steel inlet and outlet cantilever roller and its related equipment are frequent, which greatly restricts the stable operation of the steel rolling production line.

[0043] On the production line, different process steps may require different conveying speeds. By controlling the switching of the inverters in and out of the steel cantilever rollers, the production rate can be quickly adjusted and adapted to the process requirements. At the same time, during the production process, there may be low loads and high loads. Using the appropriate inverter to match the load can reduce energy consumption and improve energy efficiency. For example, when the load is low, using a lower frequency inverter can reduce energy consumption.

[0044] Therefore, a frequency converter switching control system based on the inlet and outlet steel cantilever roller is proposed, such as Figure 1 As shown, Figure 1 Schematic diagram of a frequency converter switching control system based on an inlet and outlet steel cantilever roller provided by a preferred embodiment of the present invention; it can be seen that in this preferred embodiment, the system includes:

[0045] Collection module: used to collect the running status of the steel cantilever roller body;

[0046] Construction module: used for processing and analyzing the operation status of the steel cantilever roller body and establishing a cantilever roller motion prediction model;

[0047] Determination module: used to pre-set the accident level and set the response method that meets the accident level according to the cantilever roller motion prediction model;

[0048] Execution module: used to switch the inverter according to the response method.

[0049] Wherein, the steel cantilever roller body comprises a steel cantilever roller, a frequency converter and a controller, and the steel cantilever roller comprises a plurality of rollers;

[0050] The frequency converter includes a first frequency converter, a second frequency converter, a third frequency converter and a fourth frequency converter, and the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter are controlled by the controller;

[0051] The controller can independently control the opening and closing of the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter.

[0052] For a better understanding of the connection between the inverter and the cantilever roller in the cantilever roller body, please refer to Figure 2 , Figure 2 It is a schematic diagram of the connection method between the cantilever roller and the frequency converter provided in an embodiment of the present invention.

[0053] It can be seen that the first frequency converter is connected to the motors of all rollers in the cantilever roller and drives all motors;

[0054] The second frequency converter is connected to the motors of half of the rollers in the cantilever roller and drives half of the motors;

[0055] The third frequency converter is connected to the motor of the other half of the rollers in the cantilever roller and drives the other half of the motor;

[0056] The fourth frequency converter is connected to the electrodes of all rollers in the cantilever roller and drives all motors.

[0057] Further in this preferred embodiment, the rated power of the first frequency converter and the fourth frequency converter is greater than the sum of the powers of all motors connected to the first frequency converter and the fourth frequency converter, that is, greater than the sum of the powers of all motors in the cantilever roller, and the rated power of the first frequency converter is less than the rated power of the fourth frequency converter;

[0058] The rated power of the second inverter and the third inverter is greater than the total power of all motors connected to the second inverter and the third inverter, that is, greater than the total power of half of the motors in the cantilever roller, and the rated power of the second inverter is the same as the rated power of the third inverter, the sum of the rated power of the second inverter and the rated power of the third inverter is greater than the rated power of the first inverter, and the sum of the rated power of the second inverter and the rated power of the third inverter is less than the rated power of the fourth inverter.

[0059] In this way, when replacing the inverter, if it is necessary to reduce the operating speed to replace the inverter, first change from the fourth inverter to the second inverter and the third inverter working together, and then change to the first inverter, so as to avoid the instantaneous power change caused by the fourth inverter directly changing to the first inverter. In this process, the joint action of the second inverter and the third inverter acts as a buffer.

[0060] If the inverter needs to be replaced due to the need to increase the operating speed, first change from the first inverter to the second and third inverters working together, and then change to the fourth inverter, so as to avoid the instantaneous power change caused by the direct change from the first inverter to the fourth inverter. In this process, the joint action of the second and third inverters acts as a buffer.

[0061] If the inverter needs to be replaced due to a failure of the first inverter, the controller will make the second or third inverter work alone, and drive half of the motors of the cantilever roller to work alone. Under the premise of not affecting the working efficiency, the problem of stacking caused by the accelerated running speed of the front-end steel due to the substantial increase in power can be avoided. A single inverter controlling half of the motors can also enable the steel to be transported, avoiding the problem of stacking of steel at the rear end.

[0062] If the inverter needs to be replaced due to a failure of the fourth inverter, the controller will make the second inverter or the third inverter work alone, and drive half of the motors of the cantilever roller to work alone. Without affecting the working efficiency, the problem of stacking caused by the accelerated running speed of the front-end steel due to a significant increase in power can be avoided. A single inverter controlling half of the motors can also transport the steel and avoid the problem of stacking of steel at the rear end.

[0063] Further, in this preferred embodiment, the building blocks are specifically used for:

[0064] The building module is used to collect real-time speed and load data of the cantilever roller and pre-process the data;

[0065] The building module is used to analyze the real-time speed and load of the cantilever roller, and to establish a motion prediction model of the cantilever roller according to the real-time speed and load.

[0066] In this preferred embodiment, the determination module is specifically used for:

[0067] The determination module is used to preset a first accident level for a frequency converter switching accident caused by a cantilever roller failure or maintenance;

[0068] The determination module is used to preset a second accident level for the frequency converter switching accident caused by non-fault or maintenance of the cantilever roller.

[0069] In this preferred embodiment, the determination module is specifically used for:

[0070] The determination module is used to determine that the frequency converter in use is faulty when the accident level is the first accident level, and preset switching to the second frequency converter or the third frequency converter as the first response method;

[0071] The determination module is used to determine that the inverter needs to adjust power when the accident level is the second accident level, and preset switching to the second inverter and the third inverter to output together as the second coping method.

[0072] That is, the first coping method is: if the inverter needs to be replaced due to the failure of the first inverter, the controller will make the second inverter or the third inverter work alone, and drive half of the motors of the cantilever roller to work alone. Under the premise of not affecting the working efficiency, the problem of stacking caused by the accelerated running speed of the front-end steel due to the substantial increase in power can be avoided. A single inverter controlling half of the motors can also transport the steel, avoiding the problem of stacking of the rear-end steel.

[0073] If the fourth inverter needs to be replaced due to a failure of the fourth inverter, the controller will make the second inverter or the third inverter work alone, and drive half of the motors of the cantilever roller to work alone. Under the premise of not affecting the working efficiency, the problem of stacking of steel at the front end caused by the accelerated running speed of the front end due to the substantial increase in power can be avoided. A single inverter controlling half of the motors can also enable the steel to be transported, avoiding the problem of stacking of steel at the rear end.

[0074] The second coping method is: if the inverter needs to be replaced due to the need to reduce the operating speed, first change from the fourth inverter to the second and third inverters working together, and then change to the first inverter, so as to avoid the instantaneous power change caused by the fourth inverter directly changing to the first inverter. In this process, the joint action of the second and third inverters acts as a buffer.

[0075] If the inverter needs to be replaced due to the need to increase the operating speed, first change from the first inverter to the second and third inverters working together, and then change to the fourth inverter, so as to avoid the instantaneous power change caused by the direct change from the first inverter to the fourth inverter. In this process, the joint action of the second and third inverters acts as a buffer.

[0076] In this preferred embodiment, in the determination module, the first coping method further includes:

[0077] An alarm is issued for the faulty inverter, and the controller controls the faulty inverter to not restart.

[0078] In this way, possible injuries or other engineering accidents caused by restarting the faulty inverter during the maintenance process can be avoided.

[0079] In summary, the embodiment of the present invention provides a frequency converter switching control system based on the in-and-out steel cantilever roller, which performs gradual switching when power switching is performed through the setting of four frequency converters, and gradually adjusts the motor frequency by gradually adjusting the frequency converter to achieve smooth switching;

[0080] Through the setting of the second and third frequency converters, when the first or fourth frequency converter fails, the controller will make the second or third frequency converter work alone, driving half of the motors of the cantilever roller to work alone, so as to avoid the pile-up problem caused by the acceleration of the front-end steel running speed due to the substantial increase in power without affecting the working efficiency. The single frequency converter controlling half of the motors can also make the steel be transported, avoiding the pile-up problem of the rear-end steel.

[0081] The controller prevents the faulty inverter from restarting, thereby avoiding possible injuries or other engineering accidents caused by the restart of the faulty inverter during the maintenance process.

[0082] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A frequency converter switching control system based on inlet and outlet steel cantilever rollers, characterized in that: The system comprises: Collection module: used to collect the running status of the cantilever roller body; Construction module: used for processing and analyzing the running state of the cantilever roller body and establishing a cantilever roller motion prediction model; Determination module: used to pre-set the accident level and set the response method that meets the accident level according to the cantilever roller motion prediction model; Execution module: used to switch the inverter according to the response method; The cantilever roller body comprises a cantilever roller, a frequency converter and a controller, and the cantilever roller comprises a plurality of rollers; The frequency converter includes a first frequency converter, a second frequency converter, a third frequency converter and a fourth frequency converter, and the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter are controlled by the controller; The controller can independently control the opening and closing of the first frequency converter, the second frequency converter, the third frequency converter and the fourth frequency converter; The first frequency converter is connected to the motors of all rollers in the cantilever roller and drives all the motors; The second frequency converter is connected to the motors of half of the rollers in the cantilever roller and drives half of the motors; The third frequency converter is connected to the motor of the other half of the rollers in the cantilever roller and drives the other half of the motor; The fourth frequency converter is connected to the motors of all rollers in the cantilever roller and drives all the motors; The rated power of the first frequency converter and the fourth frequency converter is greater than the total power of all motors connected to the first frequency converter and the fourth frequency converter, that is, greater than the total power of all motors in the cantilever roller, and the rated power of the first frequency converter is less than the rated power of the fourth frequency converter; The rated power of the second inverter and the third inverter is greater than the total power of all motors connected to the second inverter and the third inverter, that is, greater than the total power of half of the motors in the cantilever roller, and the rated power of the second inverter is the same as the rated power of the third inverter, the sum of the rated power of the second inverter and the rated power of the third inverter is greater than the rated power of the first inverter, and the sum of the rated power of the second inverter and the rated power of the third inverter is less than the rated power of the fourth inverter.

2. The frequency converter switching control system based on the steel cantilever roller in and out according to claim 1 is characterized in that: The building blocks are specifically used for: The building module is used to collect real-time speed and load data of the cantilever roller and pre-process the data; The building module is used to analyze the real-time speed and load of the cantilever roller, and to establish a motion prediction model of the cantilever roller according to the real-time speed and load.

3. The frequency converter switching control system based on the steel cantilever roller in and out according to claim 1 is characterized in that: The determination module is specifically used for: The determination module is used to preset a first accident level for the frequency converter switching accident caused by the cantilever roller failure; The determination module is used to preset a second accident level for the frequency converter switching accident caused by non-fault of the cantilever roller.

4. The frequency converter switching control system based on the steel cantilever roller in and out according to claim 3 is characterized in that: The determination module is specifically used for: The determination module is used to determine that the frequency converter in use is faulty when the accident level is the first accident level, and preset switching to the second frequency converter or the third frequency converter as the first response method; The determination module is used to determine that the inverter needs to adjust power when the accident level is the second accident level, and preset switching to the second inverter and the third inverter to output together as the second coping method.

5. The frequency converter switching control system based on the steel cantilever roller in and out according to claim 4 is characterized in that: In the determination module, the first coping method further includes: An alarm is issued for the faulty inverter, and the controller controls the faulty inverter to not restart.

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