Arc suppression coil control device

Abstract

The utility model provides an arc suppression coil control device, and belongs to the technical field of arc suppression coils. The arc suppression coil control device comprises a controller and a motor position detection module. The controller comprises a zero-sequence current detection module, a control module and a motor driving module, the zero-sequence current detection module is configured to detect grounding current, the output end of the zero-sequence current detection module is connected to the first signal input end of the control module, and the first signal output end of the control module is connected to the control end of the motor driving module; the motor driving module is used for controlling a motor to drive an on-load switch in the arc suppression coil to rotate to a corresponding gear; and the motor position detection module is configured to detect the position of the motor, output multiple paths of digital signals based on a motor position signal, and feed back the multiple paths of digital signals to the second signal input end of the control module through multiplexing of a plurality of cables. The problem of high failure rate caused by excessive gear shifting cables can be solved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of arc suppression coil, in particular to an arc suppression coil control device. BACKGROUND

[0002] As one of the commonly used neutral grounding protection methods in the power system of China, the arc suppression coil realizes the grounding protection through the arc suppression control device. When a single-phase grounding fault occurs in the power grid, the arc suppression coil provides a suitable inductive current to compensate the capacitive current when the single-phase grounding occurs, so that the capacitive current is reduced to below the specified value. The inductive current is realized by adjusting the tap of the on-load switch to change the inductance value. The gear control device is installed in the main control room, and needs to be connected with the gear adjusting cable between the on-load switch and the control screen. Too many gear adjusting cables will cause high failure rate and affect the stability of the equipment. CONTENT OF THE UTILITY MODEL

[0003] The embodiment of the present disclosure provides an arc suppression coil control device to solve the problem of high failure rate caused by too many gear adjusting cables.

[0004] The embodiment of the present disclosure provides an arc suppression coil control device, comprising:

[0005] a controller and a motor position detection module;

[0006] The controller comprises a zero sequence current detection module, a control module and a motor driving module, the zero sequence current detection module is configured to detect the grounding current, the output end of the zero sequence current detection module is connected to the first signal input end of the control module, the first signal output end of the control module is connected to the control end of the motor driving module, and the motor driving module is used to control the motor to drive the on-load switch in the arc suppression coil to rotate to the corresponding gear;

[0007] The motor position detection module is configured to detect the motor position, output a plurality of digital signals based on the motor position signal, and feed back the plurality of digital signals to the second signal input end of the control module through multiplexing of the plurality of cables.

[0008] In an exemplary embodiment of the present disclosure, the zero sequence current detection module comprises an amplification circuit and an A / D conversion circuit connected in sequence, the input end of the amplification circuit is used to be connected with the output end of the current sensor, and the output end of the A / D conversion circuit is connected with the first signal input end of the control module.

[0009] In an exemplary embodiment of the present disclosure, a first optoelectronic isolation module is arranged between the first signal output end of the control module and the motor driving module.

[0010] In an exemplary embodiment of the present disclosure, a second optoelectronic isolation module is arranged between the plurality of cables and the second signal input end of the control module.

[0011] In an example embodiment of the present disclosure, the zero-sequence current detection module further comprises a multi-way switch;

[0012] The plurality of signal inputs of the multi-way switch are respectively connected with the output of the current sensor, the output of the first voltage sensor and the output of the second voltage sensor, the signal output of the multi-way switch is connected with the input of the amplification circuit, and the control end of the multi-way switch is connected with the second signal output of the control module.

[0013] In an example embodiment of the present disclosure, the controller further comprises a keyboard;

[0014] The keyboard is connected with the control module.

[0015] In an example embodiment of the present disclosure, the controller further comprises a first serial port, a second serial port and a printer;

[0016] The first serial port, the second serial port and the printer are all connected with the control module.

[0017] In an example embodiment of the present disclosure, the controller further comprises an alarm module;

[0018] The alarm module is connected with the control module.

[0019] The arc suppression coil control device provided by the example embodiment of the present disclosure has the following beneficial effects:

[0020] The controller can output a control signal to the control end of the motor driving module according to the real-time detected ground current signal, so as to control the motor to drive the on-load switch in the arc suppression coil to rotate to the corresponding gear position. The motor position detection module can feed back the motor position to the second signal input end of the controller in real time, further ensuring that the on-load switch accurately stays at the predetermined gear position, improving the adjustment accuracy, effectively avoiding the problem of poor arc suppression effect caused by gear position error, and improving the safety and stability of power grid operation.

[0021] The present disclosure greatly reduces the number of cables required by cable multiplexing technology, reduces the failure risk of the control device, and can improve the reliability of the control device. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0023] Figure 1 is a structural schematic diagram of the first arc suppression coil control device provided by the example embodiment of the present disclosure;

[0024] Figure 2 is a schematic diagram of multiplexing of multiple cables provided by an embodiment of the present disclosure;

[0025] Figure 3 is a structural schematic diagram of a second arc-extinguishing coil control device provided by an embodiment of the present disclosure;

[0026] Figure 4 is a structural schematic diagram of a third arc-extinguishing coil control device provided by an embodiment of the present disclosure;

[0027] Figure 5 is a structural schematic diagram of a fourth arc-extinguishing coil control device provided by an embodiment of the present disclosure;

[0028] Figure 6 is a circuit schematic diagram of a zero-sequence current detection module provided by an embodiment of the present disclosure;

[0029] Figure 7 is a structural schematic diagram of a fifth arc-extinguishing coil control device provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] In order to enable persons skilled in the art to better understand the present scheme, the technical solutions in the present scheme embodiments will be clearly described below in conjunction with the accompanying drawings in the present scheme embodiments. Obviously, the described embodiments are part of the embodiments of the present scheme, rather than all the embodiments. Based on the embodiments in the present scheme, all other embodiments obtained by persons skilled in the art without creative labor should fall within the scope of protection of the present scheme.

[0031] The terms “include”, “comprise” and other any variants in the specification and claims of the present scheme and the above-mentioned accompanying drawings refer to “include but not limited to”, which is intended to cover non-exclusive inclusion, and is not limited to the examples listed in the text. In addition, the terms “first” and “second” and the like are used to distinguish different objects, rather than to describe a specific order.

[0032] The implementation of the present disclosure is described in detail below in conjunction with specific accompanying drawings:

[0033] Figure 1 is a structural schematic diagram of an arc-extinguishing coil control device provided by an embodiment of the present disclosure. Referring to Figure 1 The arc-extinguishing coil control device comprises a controller 101 and a motor position detection module 102.

[0034] The controller 101 comprises a zero sequence current detection module 103, a control module 104 and a motor driving module 105. The zero sequence current detection module 103 is configured to detect the grounding current. The output end of the zero sequence current detection module 103 is connected to the first signal input end of the control module 104. The first signal output end of the control module 104 is connected to the control end of the motor driving module 105. The motor driving module 105 is used to control the motor 10 to drive the on-load switch 20 in the arc-extinguishing coil to rotate to the corresponding gear.

[0035] The motor position detection module 102 is configured to detect the position of the motor 10. Based on the motor 10 position signal, a plurality of digital signals are output. The plurality of digital signals are fed back to the second signal input end of the control module 104 through multiplexing of a plurality of cables.

[0036] In the embodiment, the controller 101 is configured to control the gear adjustment of the arc-extinguishing coil.

[0037] In the power grid without grounding or with grounding through the arc-extinguishing coil, once a single-phase grounding fault occurs, the zero sequence current, i.e. the grounding current, will be generated. The zero sequence current detection module 103 can detect the grounding current signal, which is used to provide a signal basis for subsequent control actions. The magnitude of the grounding current can determine the gear to which the arc-extinguishing coil needs to be adjusted.

[0038] The first signal input end of the control module 104 is used to receive the grounding current signal transmitted by the zero sequence current detection module 103. The optimal gear to which the arc-extinguishing coil should be adjusted can be determined according to the signal. The first signal output end of the control module 104 can determine whether the gear adjustment process and the gear position of the current arc-extinguishing coil are reasonable according to the motor 10 position information fed back by the motor position detection module 102. The control module 104 can send a control instruction to the motor driving module 105 to control the gear switching of the arc-extinguishing coil.

[0039] The motor driving module 105 is configured to generate a driving signal suitable for the motor 10 according to the control instruction sent by the control module 104, and drive the motor 10 to operate. The motor 10 directly drives the on-load switch 20 in the arc-extinguishing coil to rotate, so that the arc-extinguishing coil is connected to different number of turns of windings, and the inductance is changed.

[0040] The motor position detection module 102 is configured to detect the rotor position of the motor 10, and convert the physical position information of the motor 10 into a plurality of digital signals. The plurality of digital signals are fed back to the control module 104, so that the control module 104 can master the actual situation of the motor 10 driving the on-load switch 20 to rotate, and ensure that the on-load switch 20 accurately stays at the predetermined gear, thereby avoiding the arc-extinguishing coil gear error caused by the action deviation of the motor 10, and affecting the arc-extinguishing effect.

[0041] The multiplexing of the plurality of cables can refer to Figure 2 :

[0042] The arc suppression coil control device designs 9 gears and below corresponding controller 101 number gears 1-9, 10 corresponding to gear 10, and gears 11-19 are combined from gear 10 and gears 1-9, which can be realized by only 11 cables, improves the conventional one-to-one correspondence mode, and solves the problem of too many gear cables that are prone to failure. For example, 19 gears, combined from gear 10+gear 9. Among them, the first cable to the tenth cable corresponds to gear 1 to gear 10 one by one, the eleventh cable corresponds to the signal public end (i.e. ground), at the same time, the tenth cable is one-to-one combined with the first cable to the ninth cable, which can correspond to gears 11 to 19 respectively.

[0043] From the above, the controller 101 can output a control signal to the control end of the motor drive module 105 according to the real-time detected ground current signal, to control the motor 10 to drive the on-load switch 20 in the arc suppression coil to rotate to the corresponding gear, and the motor position detection module 102 can feed back the motor 10 position to the second signal input end of the controller 101 in real time, to further ensure that the on-load switch 20 accurately stays at the predetermined gear, improve the adjustment accuracy, effectively avoid the problem of poor arc suppression effect caused by gear error, and improve the safety and stability of the power grid operation.

[0044] The present disclosure greatly reduces the number of cables required by cable multiplexing technology, reduces the failure risk of the control device, and can improve the reliability of the control device.

[0045] In an embodiment of the present disclosure, referring to Figure 3 , the zero sequence current detection module 103 includes an amplification circuit 106 and an A / D conversion circuit 107 connected in sequence, the input end of the amplification circuit 106 is used to connect with the output end of the current sensor 30, and the output end of the A / D conversion circuit 107 is connected with the first signal input end of the control module 104.

[0046] In the present embodiment, the current sensor 30 is configured to detect the zero sequence current signal in the power system. Considering that the output signal of the current sensor 30 is prone to weak signal, which cannot be directly used for subsequent digital processing or accurate control. The amplification circuit 106 is configured to amplify the output signal of the current sensor 30. Considering that the control module 104 of the current arc suppression coil control device can only process digital signals, the A / D conversion circuit 107 is configured to convert the amplified analog signal into a digital signal.

[0047] From the above, it can be concluded that the embodiment realizes accurate processing and conversion of the output signal of the current sensor 30. The amplification circuit 106 effectively enhances the signal strength, improves the anti-interference ability of the signal, and ensures the stability and accuracy of the signal in the transmission process. The A / D conversion circuit 107 converts the amplified analog signal into a digital signal, which is convenient for the control module 104 to process and analyze.

[0048] In an embodiment of the present disclosure, referring to Figure 4 , a first optoelectronic isolation module 108 is arranged between the first signal output end of the control module 104 and the motor drive module 105.

[0049] In the embodiment, the first optoelectronic isolation module 108 is configured to realize electrical isolation between the first signal output end of the control module 104 and the motor drive module 105. The first optoelectronic isolation module 108 mainly works with an optoelectronic coupler, which has a light-emitting diode (LED) and a photoelectric detector (such as a phototransistor) inside. When the control module 104 outputs a signal, the signal drives the light-emitting diode to emit light, and the photoelectric detector converts the optical signal back to an electrical signal after receiving it, and then transmits it to the motor drive module 105. The above isolation method can effectively prevent electrical interference from propagating between the control module 104 and the motor drive module 105. For example, during the operation of the motor 10, especially during the starting and stopping moments, strong electromagnetic interference will be generated. If there is no optoelectronic isolation, these interferences may be transmitted in reverse along the signal line, affecting the normal work of the control module 104, and causing the control module 104 to make a mistake, such as incorrectly adjusting the gear of the arc-extinguishing coil.

[0050] From the above, it can be concluded that the embodiment effectively isolates the electrical connection between the control module 104 and the motor drive module 105, enhances the safety and stability of the control device. Moreover, the embodiment can prevent high voltage and large current in the motor drive module 105 from interfering with the control signal, ensuring accurate transmission of control instructions, thereby improving the reliability and operating efficiency of the entire control device.

[0051] In an embodiment of the present disclosure, referring to Figure 4 , a second optoelectronic isolation module 109 is arranged between the plurality of cables and the second signal input end of the control module 104.

[0052] In this embodiment, the second opto-isolation module 109 is configured to provide electrical isolation between the multiple cables and the second signal input terminal of the control module 104. The motor position detection module 102 feeds back multiple digital signals of the motor 10's position to the control module 104 via multiple cables. However, the operating environment of the motor 10 is complex and often accompanied by strong electromagnetic interference. Without the second opto-isolation module 109, interference signals could easily affect the control module 104, causing it to misread the motor 10's position signal. The second opto-isolation module 109 also operates on the principle of an optocoupler.

[0053] As can be seen from the above, this embodiment effectively blocks electrical noise and interference signals that may exist in the cable through opto-isolation, protecting the control module 104 from external influences.

[0054] In one embodiment of this disclosure, reference is made to Figure 5 The zero-sequence current detection module 103 also includes a multiplexer 110;

[0055] The multiple signal input terminals of the multiplexer 110 are respectively connected to the output terminals of the current sensor 30, the first voltage sensor 40, and the second voltage sensor 50. The signal output terminal of the multiplexer 110 is connected to the input terminal of the amplifier circuit 106, and the control terminal of the multiplexer 110 is connected to the second signal output terminal of the control module 104.

[0056] In this embodiment, the first voltage sensor 40 is configured to detect the A-phase and B-phase voltages of the small busbar PT. The second voltage sensor 50 is configured to measure the zero-sequence voltage. The multiplexer 110 is configured to flexibly select different output signal channels according to the instructions of the control module 104 and transmit the required signal to the input terminal of the amplifier circuit 106.

[0057] Figure 6 This is a circuit diagram of the zero-sequence current detection module 103. The multiplexer 110 specifically uses a CD4051 (i.e., Figure 6 (U2 in the diagram). Pin 1 of multiplexer U2 is connected to UAB, which is the A-phase and B-phase voltage of the small bus PT. Pin 2 of multiplexer U2 is connected to the zero-sequence voltage U0. Both UAB and U0 are used to detect the operating status of the control device. If either voltage exceeds its corresponding preset threshold, an alarm signal is sent to control module 104. Pin 12 of multiplexer U2 is connected to the zero-sequence current I0. Pin 16 of multiplexer U2 is connected to the power supply voltage VCC. Pins 6 and 7 of multiplexer U2 are grounded. Pins 1, 2, 6, 7, 12, and 16 of multiplexer U2 are all signal input terminals of multiplexer 110.

[0058] Pin 8 of the multiplexer U2 is grounded, and pin 11, pin 10 and pin 9 of the multiplexer U2 are address control terminals. Different signal levels output by the second signal output terminal of the control module 104 can select any one of the UAB, zero sequence voltage U0 and zero sequence current I0 to be communicated with the signal output terminal IO of the multiplexer U2.

[0059] The signal output terminal IO of the multiplexer U2 is connected to the non-inverting input terminal of the operational amplifier U1A. The inverting input terminal of the operational amplifier U1A is grounded through the resistor R1. The output terminal of the operational amplifier U1A is connected to the inverting input terminal of the operational amplifier U1A through a multipath feedback resistor. The first switch K1, the second switch K2 and the third switch K3 are arranged in the multipath feedback resistor branch. The operational amplifier U1A, the resistor R1 and the multipath feedback resistor branch constitute a non-inverting proportional amplification circuit (a specific implementation of the amplification circuit 106), which can amplify the output signal of the multiplexer U2 to a set voltage level, facilitating accurate reading of the control module 104.

[0060] Considering that different signals UAB, zero sequence voltage U0 and zero sequence current I0 require different amplification multiples when the multiplexer U2 selects different signals, the first switch K1, the second switch K2 or the third switch K3 is turned on to select different feedback resistors, so that the amplification multiple of the amplification circuit 106 can be adjusted according to actual needs.

[0061] The first switch K1, the second switch K2 and the third switch K3 can be implemented by the multipath analog switch CD4066, and the first switch K1, the second switch K2 and the third switch K3 can be controlled by the control module 104 to be turned on or turned off.

[0062] As can be seen from the above, the multiplexer 110 can realize that multiple voltage and current detection signals share one amplification circuit 106 and A / D conversion circuit 107, so as to reduce the circuit cost. Meanwhile, the first switch K1, the second switch K2 and the third switch K3 can switch the corresponding feedback resistors according to different voltage and current detection signals, so as to adjust the amplification multiple of the amplification circuit 106 and realize accurate reading of different voltage and current detection signals by the control module 104.

[0063] In an embodiment of the present disclosure, referring to Figure 7 The controller 101 further comprises a keyboard 111.

[0064] The keyboard 111 is connected to the control module 104.

[0065] In an embodiment of the present disclosure, referring to Figure 7 The controller 101 further comprises a first serial port 112, a second serial port 113 and a printer 114.

[0066] The first serial port 112, the second serial port 113 and the printer 114 are all connected with the control module 104.

[0067] In an embodiment of the present disclosure, with reference to Figure 7 The controller 101 further comprises an alarm module 115.

[0068] The alarm module 115 is connected with the control module 104.

[0069] In the present embodiment, the keyboard 111 is configured to realize human-computer interaction, input various instructions and data to the control module 104. The operator can manually intervene the operation of the arc-extinguishing coil control device through the keyboard 111.

[0070] When the power grid operation appears abnormal and needs to urgently adjust the arc-extinguishing coil gear, the operator can quickly issue an instruction through the keyboard 111 to skip the automatic control logic and directly switch the arc-extinguishing coil to the specified gear, ensuring that the arc-extinguishing work is timely and effective. In addition, in daily maintenance, the device state information can be queried through the keyboard 111, and the device self-checking operation can be performed.

[0071] The first serial port 112 is configured to realize data communication and interaction between the controller 101 and external devices or systems. The first serial port 112 can be used to connect with the upper computer and transmit the operation data, state information, etc. of the arc-extinguishing coil control device to the upper computer.

[0072] The second serial port 113 is configured to provide a backup or extended data communication interface. It can connect other intelligent devices or sensors to extend the functions and data acquisition range of the controller 101.

[0073] The printer 114 is configured to print out important data and information of the arc-extinguishing coil control device to form paper records.

[0074] After regular inspection or troubleshooting, the printer 114 can print out the operation parameters, fault occurrence time and related data of the arc-extinguishing coil for the operation and maintenance personnel to archive and analyze.

[0075] The alarm module 115 is configured to monitor the operation state of the arc-extinguishing coil control device and timely issue an alarm signal when an abnormal situation occurs.

[0076] During normal operation, the alarm module 115 monitors the working state of the zero sequence current detection module 103, the motor drive module 105, the motor position detection module 102 and other parts in real time. Once the zero sequence current is detected to be abnormally increased beyond the set threshold, or the motor 10 position detection does not match the expected, or other fault conditions, the alarm module 115 is immediately started. The alarm module 115 can cause the attention of the on-site operator by issuing an audible and visual alarm signal, such as lighting an alarm indicator and emitting a buzzing sound. At the same time, the alarm module 115 can also send alarm information to the remote monitoring center through the first serial port 112 or other communication methods, so that the operation and maintenance personnel can know the equipment failure in time and take appropriate measures to handle it, prevent the fault from further expanding, and ensure the safe and stable operation of the power grid.

[0077] From the above, the addition of the keyboard 111 enables users to intuitively input instructions and parameters, improving the convenience and interactivity of operation. The first serial port 112 and the second serial port 113 provide rich communication interfaces for data exchange and collaborative work with other devices. The configuration of the printer 114 enables important data and reports to be printed immediately, facilitating recording and archiving. The introduction of the alarm module 115 can issue an alarm in time when an abnormality or fault is detected, enhancing the safety and reliability of the system.

[0078] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. An arc suppression coil control device, characterized in that, Includes a controller and a motor position detection module; The controller includes a zero-sequence current detection module, a control module, and a motor drive module. The zero-sequence current detection module is configured to detect grounding current. The output terminal of the zero-sequence current detection module is connected to the first signal input terminal of the control module. The first signal output terminal of the control module is connected to the control terminal of the motor drive module. The motor drive module is used to control the motor to drive the on-load switch in the arc suppression coil to rotate to the corresponding position. The motor position detection module is configured to detect the motor position, output multiple digital signals based on the motor position signal, and feed back the multiple digital signals to the second signal input terminal of the control module through multiple cables.

2. The arc suppression coil control device as described in claim 1, characterized in that, The zero-sequence current detection module includes an amplifier circuit and an A / D conversion circuit connected in sequence. The input terminal of the amplifier circuit is connected to the output terminal of the current sensor, and the output terminal of the A / D conversion circuit is connected to the first signal input terminal of the control module.

3. The arc suppression coil control device as described in claim 1, characterized in that, A first opto-isolation module is provided between the first signal output terminal of the control module and the motor drive module.

4. The arc suppression coil control device as described in claim 1, characterized in that, A second opto-isolation module is provided between the multiple cables and the second signal input terminal of the control module.

5. The arc suppression coil control device as described in claim 2, characterized in that, The zero-sequence current detection module also includes a multiplexer; The multiple signal input terminals of the multiplexer are respectively connected to the output terminals of the current sensor, the first voltage sensor, and the second voltage sensor. The signal output terminal of the multiplexer is connected to the input terminal of the amplifier circuit. The control terminal of the multiplexer is connected to the second signal output terminal of the control module.

6. The arc suppression coil control device as described in claim 1, characterized in that, The controller also includes a keyboard; The keyboard is connected to the control module.

7. The arc suppression coil control device as described in claim 1, characterized in that, The controller also includes a first serial port, a second serial port, and a printer; The first serial port, the second serial port, and the printer are all connected to the control module.

8. The arc suppression coil control device as described in claim 1, characterized in that, The controller also includes an alarm module; The alarm module is connected to the control module.

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