Frequency conversion control system

Abstract

An embodiment of the utility model provides a frequency conversion control system, which comprises a frequency converter to be controlled, a first control device, a switching device and a second control device, the switching device is connected with the frequency converter, when the switching device receives a first switching signal, a communication link is established between the frequency converter and the first control device, and the frequency converter is connected with the second control device. Moreover, when the switching device receives a second switching signal, a communication link is established between the frequency converter and the second control device, and the frequency converter is started or stopped in response to the first control signal of the first control device and / or the second control signal of the second control device. According to the scheme, simple and convenient local and remote switching control is realized, and meanwhile, the problems of multiple system fault points, high fault rate and high maintenance difficulty caused by the fact that a plurality of control buttons, relays and a large number of control circuits are arranged on the cabinet door of the frequency conversion cabinet for switching control are avoided.

Description

Technical Field

[0001] The utility model relates to the field of frequency converter control, and in particular to a frequency conversion control system. Background Art

[0002] Traditional variable frequency speed regulation solutions usually adopt a three-way switching independent control method to achieve independent control of the local inverter cabinet, local operation box and remote PLC. Specifically: 1) The three-way switching switch installed on the door of the local inverter cabinet is used to achieve independent control of the three-way switching. 2) The start button and adjustment button installed on the door of the local inverter cabinet are used to start, stop and adjust the speed of the inverter. 3) The start and stop buttons and speed potentiometer are installed on the local operation box and the remote PLC station respectively to start, stop and adjust the speed of the inverter.

[0003] In this solution, multiple control buttons, relays and a large number of control lines need to be installed on the local inverter cabinet. The system has many failure points, a high failure rate and is difficult to maintain. Utility Model Content

[0004] This embodiment provides a method to at least partially solve the above-mentioned problem.

[0005] According to an embodiment of the utility model, a frequency conversion control system includes a frequency converter to be controlled, a first control device, a switching device and a second control device, wherein the frequency converter and the first control device are locally set, and the switching device and the second control device are remotely set, the first control device and the second control device are respectively connected to the frequency converter and are configured to be able to send a first control signal and a second control signal to the frequency converter, respectively, the switching device is connected to the frequency converter, and when the switching device receives a first switching signal, the switching device establishes a communication link between the frequency converter and the first control device, and when the switching device receives a second switching signal, the switching device establishes a communication link between the frequency converter and the second control device, wherein the frequency converter starts or stops in response to the first control signal and / or the second control signal.

[0006] Furthermore, the frequency conversion control system also includes a third control device, which is connected to the frequency converter and is configured to send a third control signal to the frequency converter. When the switching device receives a third switching signal, it establishes a communication link between the frequency converter and the third control device, wherein the frequency converter starts or stops in response to the third control signal.

[0007] Based on this embodiment, the system can be used to perform switching control on multiple systems to achieve more flexible control of the frequency converter.

[0008] Furthermore, the first control signal, the second control signal and the third control signal also include a signal for controlling the frequency converter to adjust the speed.

[0009] Furthermore, the first control device is a control panel of the frequency converter, and the first control device is provided with a first start button, a first stop button and a first speed adjustment button for controlling the frequency converter. Based on this embodiment, local operation of the frequency converter is realized.

[0010] Furthermore, the second control device is a PLC control station, and the second control device includes a second start button, a second stop button and a second speed adjustment button for controlling the frequency converter.

[0011] Furthermore, the third control device is a local operation box, and the third control device includes a third start button, a third stop button and a third speed adjustment button for controlling the frequency converter.

[0012] Based on the above two embodiments, which are commonly used inverter remote control devices, based on the embodiments of the utility model, the inverter can be remotely controlled through these two remote devices.

[0013] Furthermore, the frequency conversion control system also includes a frequency converter cabinet, the frequency converter and the first control device are arranged in the frequency converter cabinet, and the switching device and the second control device are arranged outside the frequency converter cabinet.

[0014] Based on this embodiment, local and remote operations on the frequency converter cabinet are realized.

[0015] Furthermore, the frequency converter is connected to an external motor, and the external motor is connected to a cooling fan.

[0016] Based on this embodiment, a frequency conversion control system is used to control a frequency converter, and an external motor is controlled by the frequency converter, which is further applied to a cooling fan and is suitable for various related scenarios, such as a cement production line.

[0017] It can be seen that the transmission control system of the embodiment of the utility model, by setting up a frequency converter and a first control device locally, setting up a switching device and a second control device remotely, performing signal switching through the switching device, establishing a communication link between the frequency converter and the first control device, when the switching device receives a first switching signal, the frequency converter is configured to be able to receive the first control signal of the first control device, and when the switching device receives the second switching signal, a communication link is established between the frequency converter and the second control device. This solution realizes simple local and remote switching control, and at the same time, avoids the problems of multiple system failure points, high failure rate and difficult maintenance caused by setting multiple control buttons, relays and a large number of control lines on the door of the frequency converter cabinet for switching control. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0019] Figure 1 The structure diagram of the frequency conversion control system in the prior art is shown;

[0020] Figure 2 A schematic structural diagram of a frequency conversion control system according to an embodiment of the utility model is shown;

[0021] Figure 3 The flowchart of the frequency conversion control system according to an embodiment of the utility model is shown.

[0022] The reference numerals are as follows:

[0023] 1Inverter

[0024] 2Inverter cabinet

[0025] 10First control device

[0026] 15 Switching device

[0027] 20 Second control device

[0028] 30 Third control device

[0029] 50 External motor

[0030] 110 Local switch button

[0031] 120 local control buttons DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the utility model clearer, the utility model is further described in detail with examples below.

[0033] Figure 1It is a structural schematic diagram of a frequency conversion control system in the prior art;

[0034] like Figure 1 The inverter cabinet 2 is connected to the remote PLC station and the local operation box respectively. A plurality of buttons or buttons are arranged on the door of the inverter cabinet 2, such as a local switching button 110 for switching control, and a local control button 120 (including a start button, a stop button, an acceleration button, a deceleration button, etc.) for controlling the inverter locally. The switching control button is a part of the switching control loop (not shown in the figure). By operating the switching control button, the inverter can be controlled by the remote PLC station or the local operation box or the local inverter cabinet 2. The control of the remote PLC station or the control of the local operation box is controlled by their respective start-stop buttons and speed control buttons, respectively, and the control of the local inverter cabinet 2 is controlled by the start button, stop button or speed control button on the door of the inverter cabinet 2.

[0035] It can be seen that in the above existing solutions, the inverter needs to be switched and controlled on the door of the inverter cabinet 2, and remote switching control cannot be achieved. In addition, various control lines, control buttons, etc. are installed on the door of the inverter cabinet 2, which makes the system have many failure points, high failure rate and great maintenance difficulty.

[0036] Figure 2 The figure is a schematic structural diagram of a frequency conversion control system according to an embodiment of the utility model.

[0037] like Figure 2 The frequency conversion control system of the illustrated embodiment includes a frequency converter to be controlled, a first control device 10, a switching device 15 and a second control device 20, wherein the frequency converter and the first control device 10 are locally set, and the switching device 15 and the second control device 20 are remotely set, the first control device 10 and the second control device 20 are respectively connected to the frequency converter and are configured to be able to send a first control signal and a second control signal to the frequency converter, respectively, the switching device 15 is connected to the frequency converter, and when the switching device 15 receives a first switching signal, the switching device 15 establishes a communication link between the frequency converter and the first control device 10, and, when the switching device 15 receives a second switching signal, the switching device 15 establishes a communication link between the frequency converter and the second control device 20, wherein the frequency converter starts or stops in response to the first control signal and / or the second control signal.

[0038] Specifically, a Siemens G150 inverter can be used, and an AOP30 control panel can be used as the first control device 10 to control the G150 inverter. The first control panel is provided with a start button, a stop button, etc., which can send a first control signal including at least controlling the start and stop of the inverter to the inverter, so as to start and stop the inverter. The switching device 15 is, for example, a multi-gear switch structure, which is connected to the inverter. The inverter is configured to receive an operation signal on the switching device 15. For example, the switching device 15 includes two gears, the first gear is connected to the first control device 10, and the second gear is connected to the second control device 20. When the user operates the switching device 15 to the first gear, the inverter recognizes the first switching signal at this time. When the user operates the switching device 15 to the second gear, the inverter recognizes that it is the second switching signal at this time.

[0039] Optionally, the frequency converter is configured to judge the received signal of the switching device 15 based on the internal parameters and the configuration of the free function block to connect the first control device 10 or the second control device 20. It should be noted that the implementation of this function through the configuration of the internal parameters and the free function block is an adaptive configuration made by those skilled in the art based on the frequency converter, without the need for creative work.

[0040] Further, the frequency conversion control system based on the above embodiment also includes a third control device 30, the third control device 30 is connected to the frequency converter and is configured to be able to send a third control signal to the frequency converter, the switching device 15 is also configured to be able to receive a third switching signal, and the frequency converter is configured to receive the third control signal sent by the third control device 30 when the switching device 15 receives the third switching signal, and the third control signal at least includes a signal for controlling the frequency converter to start and stop. Based on this embodiment, the switching device 15 can also be connected to the third control device 30 to achieve more flexible control of the frequency converter.

[0041] Furthermore, one or more other remote control devices may be provided, each of which is connected to the frequency converter and is configured to be able to send a control signal for controlling the frequency converter to the frequency converter; in addition, the switching device 15 is also configured to be able to receive more switching signals, for example, it also includes a fourth control device, and the switching device 15 is also configured to be able to receive a fourth switching signal. When the frequency converter recognizes that the switching device 15 has received the fourth switching signal, it activates the control of the fourth control device and takes over the control of the fourth control device.

[0042] Furthermore, the first control signal, the second control signal and the third control signal also include a signal for controlling the frequency converter to adjust the speed. Based on this embodiment, the control of the frequency converter can be speed control in addition to start-stop control, and of course, can also include other controls. It is easy for those skilled in the art to incorporate various controls into the solution.

[0043] Furthermore, it includes a frequency converter cabinet 2 , the frequency converter and the first control device 10 are arranged in the frequency converter cabinet 2 , and the switching device 15 and the second control device 20 are arranged outside the frequency converter cabinet 2 .

[0044] Based on this embodiment, by providing this type of frequency converter cabinet 2 , the needs of multi-party switching control can be met, thereby expanding the application field of the frequency converter cabinet 2 .

[0045] Furthermore, the first control device 10 is a control panel of the frequency converter, and the first control device 10 is provided with a first start button, a first stop button and a first speed adjustment button for controlling the frequency converter.

[0046] Based on this embodiment, the control panel of the inverter itself is used as the first control device 10. The first start button, the first stop button, and the first speed adjustment button in the first control device 10 can directly control the inverter without additionally setting switch buttons, control loops, etc. on the inverter cabinet 2, thereby saving hardware costs and shortening the hardware development time of the inverter cabinet 2.

[0047] Furthermore, the second control device 20 is a PLC control station, and the second control device 20 includes a second start button, a second stop button and a second speed adjustment button for controlling the frequency converter.

[0048] Control through PLC is a common way to control the frequency converter. By operating the second start button, the second stop button, and the second speed control button of the PLC control station, the start and stop of the frequency converter and the analog speed control can be realized. In this solution, when the PLC control station is used as one of the multi-party switching controls, there is no need to make any adjustments to the PLC program. The entire system optimization only needs to be performed on one side of the frequency converter or the frequency converter cabinet 2, which reduces the difficulty and cost of system implementation.

[0049] Furthermore, the third control device 30 is a local operation box, and the third control device 30 includes a third start button, a third stop button and a third speed adjustment button for controlling the frequency converter.

[0050] The local operation box is a common way to operate the inverter locally. It is easy to operate and is widely used in environments where the equipment operates stably. By operating the third start button, the third stop button, and the third speed control button of the local operation box, the start and stop of the inverter and the speed control of the speed potentiometer can be realized. In this solution, when the local operation box is used as one of the multi-party switching controls, there is no need to make any changes to the local operation box. The entire system optimization only needs to be performed on one side of the inverter or the inverter cabinet 2, which reduces the difficulty and cost of system implementation.

[0051] Figure 3 FIG. 2 shows the working process of a frequency conversion control system according to an embodiment of the utility model. Figure 3 As shown, the workflow includes:

[0052] 1) After the local inverter is powered on, the inverter automatically initializes the parameters;

[0053] 2) The frequency converter judges the switching signal of the switching device 15 to avoid erroneous operation caused by three-party signals;

[0054] 3) When the switching device 15 has not switched to the first gear, that is, when the frequency converter receives the first switching signal of the switching device 15, the control of the operation panel of the frequency converter is activated. At this time, the start button, stop button, and speed adjustment button of the operation panel can be used to start, stop, and adjust the speed of the frequency converter.

[0055] 4) When the switching device 15 switches to the second gear, that is, when the frequency converter receives the second switching signal of the switching device 15, the control of the PLC control station is activated. At this time, the second start button, the second stop button and the second speed adjustment button of the PLC control station can send a second control signal to the frequency converter to realize the start, stop and speed adjustment control of the frequency converter;

[0056] 5) When the switching device 15 is switched to the third gear, that is, when the frequency converter receives the third switching signal of the switching device 15, the operation of the local operation box is activated. At this time, the third start button, the third stop button and the third speed adjustment button on the local operation box can be used to send a third control signal to the frequency converter to realize the start, stop and speed adjustment control of the frequency converter;

[0057] Furthermore, in the variable frequency control system of the present invention, the frequency converter is connected to the external motor 50, and the external motor 50 is connected to the cooling fan.

[0058] Specifically, according to the frequency conversion control system of the embodiment of the utility model, the usage scenario can be the frequency conversion speed regulation of the cooling fan of a large production line. The frequency conversion control system of this embodiment can realize switchable control of the local inverter cabinet 2, the local operation box, and the remote PLC control station.

[0059] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0060] Nouns and pronouns relating to persons in this patent application are not limited to a specific gender.

Claims

1. Frequency conversion control system, characterized in that: The invention comprises a frequency converter (1) to be controlled, a first control device (10), a switching device (15) and a second control device (20), wherein the frequency converter (1) and the first control device (10) are locally arranged, and the switching device (15) and the second control device (20) are remotely arranged, the first control device (10) and the second control device (20) are respectively connected to the frequency converter (1) and are arranged to be able to send a first control signal and a second control signal to the frequency converter (1), respectively, the switching device (15) is connected to the frequency converter (1), and when the switching device (15) receives a first switching signal, the switching device (15) establishes a communication link between the frequency converter (1) and the first control device (10), and when the switching device (15) receives a second switching signal, the switching device (15) establishes a communication link between the frequency converter (1) and the second control device (20), wherein the frequency converter (1) is started or stopped in response to the first control signal and / or the second control signal.

2. The frequency conversion control system according to claim 1, characterized in that: The invention also includes a third control device (30), which is connected to the frequency converter and is configured to send a third control signal to the frequency converter. When the switching device (15) receives a third switching signal, it establishes a communication link between the frequency converter and the third control device (30), wherein the frequency converter starts or stops in response to the third control signal.

3. The frequency conversion control system according to claim 2, characterized in that: The first control signal, the second control signal and the third control signal also include signals for controlling the frequency converter to adjust the speed.

4. The frequency conversion control system according to claim 1, characterized in that: The first control device (10) is a control panel of the frequency converter, and the first control device (10) is provided with a first start button, a first stop button and a first speed adjustment button for controlling the frequency converter.

5. The frequency conversion control system according to claim 1, characterized in that: The second control device (20) is a PLC control station, and the second control device (20) comprises a second start button, a second stop button and a second speed adjustment button for controlling the frequency converter.

6. The frequency conversion control system according to claim 2, characterized in that: The third control device (30) is a local operation box, and comprises a third start button, a third stop button and a third speed adjustment button for controlling the frequency converter.

7. The frequency conversion control system according to claim 1, characterized in that: It comprises a frequency converter cabinet (2), wherein the frequency converter and the first control device (10) are arranged in the frequency converter cabinet (2), and the switching device (15) and the second control device (20) are arranged outside the frequency converter cabinet (2).

8. The frequency conversion control system according to claim 1, characterized in that: The frequency converter is connected to an external motor (50), and the external motor (50) is connected to a cooling fan.

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