Intelligent capacitor device

Abstract

The utility model provides an intelligent capacitor device, and relates to the technical field of electrical equipment. The intelligent capacitor device comprises a capacitor, a fling-cut switch and a controller. The fling-cut switch comprises a driving module and a plurality of switch modules. Each switch module comprises a plurality of switch units connected in series, the first switch unit connected in series is connected with the output end of the three-phase alternating current, the last switch unit connected in series is connected with the capacitor, the control ends of the switch units are connected with the output end of the driving module, and the input end of the driving module is connected with the controller. In the application, the controller can dynamically select the target switch unit and the non-target switch unit of the switch module according to the actual switching frequency of each switch unit in the switch module; the non-target switch unit is always in a closed state, and only the target switch unit is controlled by the controller through the driving module to be switched on and switched off, so that the switch module is controlled to be switched on and switched off, and the capacitor is switched on and switched off.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and more particularly to a smart capacitor device. Background Technology

[0002] With the rapid development of power systems and the continuous improvement of power quality requirements, reactive power compensation equipment plays an increasingly important role in power systems. Reactive power compensation not only improves the power factor of the power grid and reduces line losses, but also enhances the stability and security of the power system. As an important component of reactive power compensation equipment, intelligent capacitor banks are widely used in various power systems to regulate the reactive power of the power grid in real time.

[0003] In existing technologies, magnetic latching relays are typically used as switching switches when switching capacitors in intelligent capacitor banks. While magnetic latching relays offer high mechanical strength and fast response characteristics, they are prone to contact wear during frequent switching operations, leading to a shortened electrical life. This makes it difficult to meet the stability and durability requirements for frequent capacitor switching, thus affecting the overall reliability of the intelligent capacitor bank. Utility Model Content

[0004] This application provides an intelligent capacitor device that can effectively extend the electrical life of the switching switch, meet the stability and durability requirements of frequent capacitor switching, and improve the reliability of the intelligent capacitor device.

[0005] This application provides an intelligent capacitor device, including: a capacitor, a switching switch, and a controller.

[0006] The switching switch includes a drive module and multiple switch modules.

[0007] Each of the switching modules includes multiple switching units connected in series. The first switching unit connected in series is connected to the output terminal of the three-phase AC power supply, and the last switching unit connected in series is connected to the capacitor. The control terminals of the multiple switching units are all connected to the output terminal of the drive module, and the input terminal of the drive module is connected to the controller.

[0008] When the capacitor is disconnected, the controller controls the target switching unit in each of the switching modules to open and the non-target switching unit in each of the switching modules to close via the drive module.

[0009] When the capacitor is connected, the controller controls the target switch unit in each switch module to close via the drive module, and controls the non-target switch units in each switch module to remain closed.

[0010] The target switch unit is a switch unit in the switch module whose actual switching count is less than the preset switching count, and the non-target switch unit is any other switch unit in the switch module besides the target switch unit.

[0011] The above scheme involves a switching switch comprising multiple switching modules, each module containing multiple series-connected switching units. The controller dynamically selects the target switching unit of the switching module based on the actual number of switching operations for each switching unit. The controller identifies the switching units in the module whose actual switching operations are less than a preset number as the target switching units, and designates all other switching units as non-target units. The non-target switching units remain closed; only the target switching unit is controlled by the controller via a drive module to open and close, thereby controlling the opening and closing of the switching module and enabling the connection and disconnection of the capacitor. Compared to existing technologies, this application effectively disperses the switching operations of a single switching unit by dynamically selecting the target and non-target switching units, avoiding contact wear caused by frequent switching operations, effectively extending the service life of the switching switch, and meeting the stability and durability requirements for frequent capacitor switching, thus significantly improving the reliability of the intelligent capacitor device.

[0012] In some embodiments, when the three-phase AC power is a three-phase four-wire AC power and the capacitor is a sub-compensating capacitor, the number of the switching modules is three, and the three switching modules correspond one-to-one with phases A, B and C of the three-phase four-wire AC power.

[0013] In some embodiments, when the three-phase AC power is a three-phase three-wire AC power and the capacitor is a common compensation capacitor, the number of the switching modules is two, and the two switching modules correspond one-to-one with phase A and phase C of the three-phase three-wire AC power.

[0014] In some embodiments, the device further includes a first voltage detection module and a current detection module.

[0015] The input terminal of the first voltage detection module is connected to the output terminal of the three-phase AC power, and the output terminal of the first voltage detection module is connected to the controller. The first voltage detection module is used to detect the first voltage parameter of the three-phase AC power.

[0016] The input terminal of the current detection module is connected to the output terminal of the three-phase AC power, and the output terminal of the current detection module is connected to the controller. The current detection module is used to detect the current parameters of the three-phase AC power.

[0017] In some embodiments, when the three-phase AC power is a three-phase four-wire AC power and the capacitor is a shunt capacitor, the first voltage detection module includes three first voltage detection units, and the current detection module includes three first current detection units.

[0018] The three first voltage detection units and the three first current detection units correspond one-to-one with phases A, B, and C of the three-phase four-wire AC power supply.

[0019] In some embodiments, when the three-phase AC power is three-phase three-wire AC power and the capacitor is a common compensation capacitor, the first voltage detection module includes two second voltage detection units, and the current detection module includes two second current detection units.

[0020] The two second voltage detection units and the two second current detection units correspond one-to-one with the A phase and C phase of the three-phase three-wire AC power.

[0021] In some embodiments, the device further includes a second voltage detection module.

[0022] The first input terminal of the second voltage detection module is connected to the output terminal of the three-phase AC power supply, the second input terminal of the second voltage detection module is connected to the capacitor, and the first and second output terminals of the second voltage detection module are both connected to the controller. The second voltage detection module is used to detect the second voltage parameter and the third voltage parameter at both ends of the switching module.

[0023] In some embodiments, the device further includes a display controlled by the controller.

[0024] In some embodiments, the device further includes a communication module, one end of which is connected to the controller and the other end of which is connected to a monitoring computer.

[0025] In some embodiments, the communication module is an RS485 communication module.

[0026] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0027] Figure 1 This is a circuit block diagram of a smart capacitor device provided in an embodiment of this application.

[0028] Figure 2A circuit block diagram of another intelligent capacitor device provided in an embodiment of this application.

[0029] Figure 3 This is a circuit block diagram of another intelligent capacitor device provided in an embodiment of this application.

[0030] Figure 4 A circuit block diagram of another intelligent capacitor device provided in an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures:

[0032] 10. Capacitors;

[0033] 20. Switch;

[0034] 21. Driver module; 22. Switch module;

[0035] 221. Switching unit;

[0036] 30. Controller;

[0037] 40. Three-phase alternating current;

[0038] 50. First voltage detection module;

[0039] 60. Current detection module;

[0040] 70. Second voltage detection module;

[0041] 80. Monitor;

[0042] 90. Communication module;

[0043] 100. Monitor computers. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims and drawings of this application are intended to cover non-exclusive inclusion.

[0046] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of the phrase "embodiment" in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0047] Furthermore, the terms "first," "second," etc., in the specification and claims of this application or in the aforementioned drawings are used to distinguish different objects rather than to describe a specific order, and may explicitly or implicitly include one or more of the features.

[0048] In the description of this application, unless otherwise stated, "multiple" means two or more (including two), and similarly, "multiple groups" means two or more (including two groups).

[0049] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, "connection" or "joining" in mechanical structures can refer to a physical connection, such as a fixed connection, for example, a connection fixed by a partition, such as a connection fixed by screws, bolts, or other partitions; a physical connection can also be a detachable connection, such as a snap-fit ​​or interlocking connection; a physical connection can also be an integral connection, such as a connection formed by welding, bonding, or integral molding. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0050] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0051] Figure 1 This is a circuit block diagram of a smart capacitor device provided in an embodiment of this application. Figure 1 As shown, the intelligent capacitor device includes a capacitor 10, a switching switch 20, and a controller 30.

[0052] The switching switch 20 includes a drive module 21 and multiple switch modules 22.

[0053] Each switching module 22 includes multiple switching units 221 connected in series. The first switching unit 221 connected in series is connected to the output terminal of the three-phase AC power 40, and the last switching unit 221 connected in series is connected to the capacitor 10. The control terminals of the multiple switching units 221 are all connected to the output terminal of the drive module 21, and the input terminal of the drive module 21 is connected to the controller 30.

[0054] When capacitor 10 is disconnected, controller 30 controls the target switching unit in each switching module 22 to open via drive module 21, and controls the non-target switching unit in each switching module 22 to close.

[0055] When capacitor 10 is connected, controller 30 controls the target switch unit in each switch module 22 to close via drive module 21, and controls the non-target switch unit in each switch module 22 to remain closed.

[0056] The target switch unit is a switch unit in switch module 22 whose actual switching count is less than the preset switching count, and the non-target switch unit is any other switch unit in switch module 22 other than the target switch unit.

[0057] It should be noted that capacitor 10 is a device used for reactive power compensation in power systems. By providing capacitive reactive power, capacitor 10 improves the power factor of the three-phase AC power 40 in the power grid, reduces power loss, stabilizes voltage, and thus improves the efficiency of the power grid.

[0058] In some embodiments, capacitor 10 is a split-compensation capacitor. The split-compensation capacitor can be independently controlled by switching switch 20 to independently compensate for a single phase of the three-phase AC power 40, so that phases A, B and C of the three-phase AC power 40 can work independently and better cope with unbalanced three-phase loads.

[0059] In some other embodiments, capacitor 10 is a common compensation capacitor. The common compensation capacitor is used to uniformly compensate the three phases of the three-phase AC power 40, so that phases A, B and C of the three-phase AC power 40 work simultaneously. It is suitable for three-phase AC power 40 where the load is relatively balanced and the overall power factor needs to be improved.

[0060] It should be noted that the switching switch 20 is a switching device used to switch capacitor 10 in the intelligent capacitor device. Capacitor 10 includes three compensation capacitors. When capacitor 10 is a separate compensation capacitor, the three compensation capacitors of capacitor 10 are connected in a Y-shape; when capacitor 10 is a common compensation capacitor, the three compensation capacitors of capacitor 10 are connected in a delta shape.

[0061] The drive module 21 is used to receive drive commands sent by the controller 30 and drive the switch unit 221 in the switch module 22 to operate according to the drive commands. The structure of the drive module 21 is the same as that of the drive module used to drive the switch unit 221 in the prior art, and will not be described again in this embodiment.

[0062] The multiple switching modules 22 included in the switching switch 20 have the same structure. Each switching module 22 is connected in series between the three-phase AC power 40 and the capacitor 10. One end of the switching module 22 is connected to the output terminal of the three-phase AC power 40, and the other end of the switching module 22 is connected to the input terminal of the capacitor 10.

[0063] For any one of the multiple switch modules 22, the switch module 22 includes multiple switch units 221 connected in series.

[0064] Specifically, when multiple switching units 221 of the switching module 22 are connected in series, the normally open contacts of the multiple switching units 221 are connected in series sequentially. When all normally open contacts of the multiple switching units 221 of the switching module 22 are closed, the switching module 22 is closed; when the normally open contact of any one of the multiple switching units 221 of the switching module 22 is open, the switching module 22 is open.

[0065] For example, the switch module 22 includes three switch units 221 connected in series, which are a first switch unit, a second switch unit, and a third switch unit, respectively. The moving contact of the normally open contact of the first switch unit is connected to the output terminal of the three-phase AC power supply 40, the stationary contact of the normally open contact of the first switch unit is connected to the moving contact of the normally open contact of the second switch unit, the stationary contact of the normally open contact of the second switch unit is connected to the moving contact of the normally open contact of the third switch unit, and the stationary contact of the normally open contact of the third switch unit is connected to the input terminal of the capacitor 10.

[0066] Magnetic latching relays are a new type of relay that has appeared on the market in recent years. They are also a type of automatic switch, functioning similarly to other electromagnetic relays, automatically connecting and disconnecting circuits. The normally closed or normally open state of a magnetic latching relay relies entirely on the action of a permanent magnet. Its switching state transition is triggered by a pulse electrical signal of a certain width. Compared to ordinary relays, it has advantages such as energy saving, high stability, small size, and high load capacity.

[0067] The switching unit 221 can be a magnetic latching relay or other devices that can switch capacitors; this embodiment does not specifically limit this.

[0068] It should be noted that the controller 30 can determine whether the capacitor 10 needs to be switched on or off based on the power factor of the three-phase AC power 40. The method by which the controller 30 determines whether the capacitor 10 needs to be switched on or off based on the power factor of the three-phase AC power 40 is a conventional method, and will not be described in detail in this embodiment.

[0069] It should be noted that whether capacitor 10 is being put into operation or removed, the non-target switching unit in each switching module 22 remains closed. The controller 30 only needs to drive the target switching unit in each switching module 22 to close or open through the drive module 21 to control the closing or opening of each switching module 22, thereby realizing the putting into or removing of capacitor 10.

[0070] For each of the multiple switching modules 22, among the multiple series-connected switching units 221 included in the switching module 22, there is one target switching unit and multiple non-target switching units. The target switching unit is a switching unit 221 in the switching module 22 whose actual switching count is less than a preset switching count, and the non-target switching units are the other switching units in the switching module 22 besides the target switching unit.

[0071] The preset number of switching operations is the maximum number of switching operations allowed by the switching unit 221. The preset number of switching operations can be set by the operation and maintenance personnel themselves, and this embodiment does not make specific limitations on this.

[0072] For example, the preset number of throws is 1000.

[0073] It should be noted that the target switching unit of the switching module 22 is the switching unit 221 in the switching module 22 whose actual switching count is less than the preset number. The target switching unit is dynamically determined by the controller 30 based on the actual switching count of the switching unit 221 and the preset switching count.

[0074] During the use of the intelligent capacitor device, the selection of the target switching unit in each switching module 22 is dynamic and controlled by the controller 30. When the actual switching count of the target switching unit in the switching module 22 exceeds the preset switching count, the controller 30 can replace the target switching unit with a non-target switching unit and select other switching units 221 with an actual switching count less than the preset switching count as the new target switching unit. This avoids frequent switching concentrated on a single switching unit 221 in the switching module 22, thereby improving the overall reliability of the intelligent capacitor device.

[0075] For each switch module 22, if there are at least two switch units 221 in the switch module 22 whose actual switching count is less than the preset switching count, the controller 30 can randomly select any one of the at least two switch units 221 as the target switch unit of the switch module 22.

[0076] In this embodiment, the switching switch 20 includes multiple switching modules 22, each of which includes multiple switching units 221 connected in series. The controller 30 can dynamically select the target switching unit of the switching module 22 based on the actual number of switching operations of each switching unit 221 in the switching module 22. The controller 30 determines the switching units 221 in the switching module 22 whose actual number of switching operations is less than a preset number of switching operations as the target switching units of the switching module 22, and determines all other switching units 221 in the switching module 22 as non-target switching units of the switching module 22. The non-target switching units of the switching module 22 are always in a closed state. Only the target switching units of the switching module 22 are controlled by the controller 30 through the drive module 21 to close and open, thereby controlling the closing and opening of the switching module 22 and realizing the connection and disconnection of the capacitor 10. Compared with the prior art, this application effectively disperses the switching frequency of a single switching unit 221 by dynamically selecting the target switching unit and non-target switching unit of the switching module 22, avoiding contact wear caused by frequent switching operations of the single switching unit 221, effectively extending the service life of the switching switch 20, and also meeting the stability and durability requirements of the capacitor 10 for frequent switching, thereby significantly improving the reliability of the intelligent capacitor device.

[0077] In some embodiments, when the three-phase AC power 40 is a three-phase four-wire AC power and the capacitor 10 is a sub-compensation capacitor, the number of switch modules 22 is three, and the three switch modules 22 correspond one-to-one with the A phase, B phase and C phase of the three-phase four-wire AC power.

[0078] It should be noted that a three-phase four-wire alternating current system includes three phase wires (phase A, phase B, and phase C) and one neutral wire (phase N).

[0079] Individual compensation capacitors are used to compensate for reactive power in loads of a single phase. That is, each phase line in phases A, B, and C has an independent compensation capacitor to compensate for the reactive power of that phase.

[0080] The three switch modules 22 correspond one-to-one with the three phase lines of the three-phase four-wire AC power supply, and each switch module 22 controls the reactive power compensation of one phase line.

[0081] Figure 2 A circuit block diagram of another intelligent capacitor device provided in an embodiment of this application. (See diagram below.) Figure 2As shown, specifically, the three switch modules 22 are the first switch module, the second switch module, and the third switch module. The input terminal of the first switch module is connected to the output terminal of phase A of the three-phase four-wire AC power supply, and the output terminal of the first switch module is connected to the first input terminal of the compensation capacitor. The input terminal of the second switch module is connected to the output terminal of phase B of the three-phase four-wire AC power supply, and the output terminal of the second switch module is connected to the second input terminal of the compensation capacitor. The input terminal of the third switch module is connected to the output terminal of phase C of the three-phase four-wire AC power supply, and the output terminal of the third switch module is connected to the third input terminal of the compensation capacitor. The output terminal of phase N of the three-phase four-wire AC power supply is directly connected to the fourth input terminal of the compensation capacitor.

[0082] The controller 30 can control the switching state of the target switching unit of the first switching module through the drive module 21 to achieve independent reactive power compensation control of phase A of the three-phase four-wire AC power. The controller 30 can also control the switching state of the target switching unit of the second switching module through the drive module 21 to achieve independent reactive power compensation control of phase B of the three-phase four-wire AC power. The controller 30 can also control the switching state of the target switching unit of the third switching module through the drive module 21 to achieve independent reactive power compensation control of phase C of the three-phase four-wire AC power.

[0083] For example, when the controller 30 determines that reactive power compensation is required for phase A of the three-phase four-wire AC power, but not for phases B and C of the three-phase four-wire AC power, the controller 30 controls the target switch unit of the first switch module to close through the drive module 21, and controls the target switch units of the second and third switch modules to open, thereby realizing independent reactive power compensation control for phase A of the three-phase four-wire AC power.

[0084] For example, when the controller 30 determines that reactive power compensation is required for phases A and B of the three-phase four-wire AC power, but not for phase C, the controller 30 controls the target switching units of the first and second switching modules to close via the drive module 21, and controls the target switching unit of the third switching module to open, thereby achieving independent reactive power compensation control for phases A and B of the three-phase four-wire AC power.

[0085] In this embodiment, by setting three switching modules, each corresponding to one of the A, B, and C phases of a three-phase four-wire AC power supply, independent reactive power compensation control of the A, B, and C phases can be achieved. This allows each phase of the three-phase four-wire AC power supply to individually connect or disconnect the capacitor 10 according to the load conditions, effectively reducing the risks of overcompensation and undercompensation. Simultaneously, the controller 30 independently controls the three switching modules, reducing the wear and maintenance costs of the intelligent capacitor device and improving its operational stability.

[0086] In some embodiments, when the three-phase AC power 40 is a three-phase three-wire AC power and the capacitor 10 is a common compensation capacitor, the number of switch modules 22 is two, and the two switch modules 22 correspond one-to-one with the A phase and C phase of the three-phase three-wire AC power.

[0087] It should be noted that three-phase three-wire alternating current includes three phase wires (phase A, phase B, and phase C).

[0088] Common compensation capacitors are used to simultaneously compensate for reactive power in three-phase three-wire AC power supply A, B, and C phases.

[0089] The two switch modules 22 correspond one-to-one with the A and C phases of the three-phase three-wire AC power. The B phase of the three-phase three-wire AC power is not connected to the switch module 22, but is directly connected to the common compensation capacitor.

[0090] Figure 3 This is a circuit block diagram of another intelligent capacitor device provided in an embodiment of this application. Figure 3 As shown, the two switch modules 22 are the fourth switch module and the fifth switch module, respectively. The input terminal of the fourth switch module is connected to the output terminal of phase A of the three-phase three-wire AC power supply, and the output terminal of the fourth switch module is connected to the first input terminal of the common compensation capacitor. The input terminal of the fifth switch module is connected to the output terminal of phase C of the three-phase three-wire AC power supply, and the output terminal of the fifth switch module is connected to the second input terminal of the common compensation capacitor. The output terminal of phase B of the three-phase three-wire AC power supply is directly connected to the third input terminal of the common compensation capacitor. The controller 30 can simultaneously control the switching states of the target switch units of the fourth switch module and the fifth switch module through the drive module 21 to achieve reactive power compensation control of the three-phase three-wire AC power supply.

[0091] The target switch units of the fourth switch module and the target switch units of the fifth switch module have the same switching state. The controller 30 controls the target switch units of the fourth switch module and the target switch units of the fifth switch module to close simultaneously through the drive module 21. Alternatively, the controller 30 controls the target switch units of the fourth switch module and the target switch units of the fifth switch module to open simultaneously through the drive module 21.

[0092] In this embodiment, by setting two switching modules, each corresponding one-to-one with phase A and phase C of the three-phase three-wire AC power, synchronous control of the common compensation capacitor is achieved. Utilizing the balance characteristics of the three-phase three-wire AC power, reactive power compensation for the entire three-phase three-wire AC power can be achieved simply by controlling the reactive power compensation of phases A and C. This reduces the number of switching modules 22 in the switching switch 20, lowers the structural complexity of the intelligent capacitor device, reduces wear and maintenance costs, and improves the operational stability of the intelligent capacitor device.

[0093] Figure 4 A circuit block diagram of another intelligent capacitor device provided in an embodiment of this application. Figure 4 As shown, in some embodiments, the smart capacitor device further includes a first voltage detection module 50 and a current detection module 60.

[0094] The input terminal of the first voltage detection module 50 is connected to the output terminal of the three-phase AC power 40, and the output terminal of the first voltage detection module 50 is connected to the controller 30. The first voltage detection module 50 is used to detect the first voltage parameter of the three-phase AC power 40.

[0095] The input terminal of the current detection module 60 is connected to the output terminal of the three-phase AC power 40, and the output terminal of the current detection module 60 is connected to the controller 30. The current detection module 60 is used to detect the current parameters of the three-phase AC power 40.

[0096] It should be noted that the first voltage detection module 50 is used to detect the first voltage parameter of the three-phase AC power 40 and send the detected first voltage parameter to the controller 30; the current detection module 60 is used to detect the current parameter of the three-phase AC power 40 and send the detected current parameter to the controller 30; so that the controller 30 can determine the power factor of the three-phase AC power 40 based on the received first voltage parameter and current parameter, and then determine whether reactive power compensation is needed for the three-phase AC power 40.

[0097] The method by which the controller 30 determines the power factor of the three-phase AC power 40 based on the first voltage and current parameters of the three-phase AC power 40, and the method by which the controller 30 determines whether reactive power compensation is required for the three-phase AC power 40 based on the power factor of the three-phase AC power 40, are existing methods and will not be described in detail in this implementation.

[0098] In this embodiment, the first voltage parameter of the three-phase AC power 40 is collected by the first voltage detection module 50, and the current parameter of the three-phase AC power 40 is collected by the current detection module 60. This allows the controller 30 to determine the power factor of the three-phase AC power 40 based on the first voltage and current parameters, and then dynamically decide whether to perform reactive power compensation on the three-phase AC power 40 based on the power factor. This can effectively avoid overcompensation of the three-phase AC power 40, thereby avoiding unnecessary wear of the intelligent capacitor device.

[0099] In some embodiments, when the three-phase AC power 40 is a three-phase four-wire AC power and the capacitor 10 is a sub-compensating capacitor, the first voltage detection module 50 includes three first voltage detection units, and the current detection module 60 includes three first current detection units.

[0100] The three first voltage detection units and the three first current detection units correspond one-to-one with the A, B and C phases of the three-phase four-wire AC power supply.

[0101] It should be noted that for each first voltage detection unit, the first input terminal of the first voltage detection unit is connected to the output terminal of the phase line of the corresponding three-phase four-wire AC power, the second input terminal of the first voltage detection unit is connected to the output terminal of the N phase of the three-phase four-wire AC power, and the output terminal of the first voltage detection unit is connected to the controller 30.

[0102] The first voltage detection unit is used to detect the phase voltage of the corresponding phase line of the three-phase four-wire AC power supply. The first voltage detection unit corresponding to phase A of the three-phase four-wire AC power supply is used to detect the phase voltage U between phase A and phase N of the three-phase four-wire AC power supply. AN The first voltage detection unit corresponding to phase B of the three-phase four-wire AC power supply is used to detect the phase voltage U between phase B and phase N of the three-phase four-wire AC power supply. BN The first voltage detection unit corresponding to phase C of the three-phase four-wire AC power supply is used to detect the phase voltage U between phase C and phase N of the three-phase four-wire AC power supply. CN .

[0103] The structure of the first voltage detection unit is the same as that of the voltage detection unit used for detecting phase voltage in the prior art, and will not be described again in this embodiment.

[0104] It should be noted that for each first current detection unit, the input terminal of the first current detection unit is connected to the output terminal of the phase line of the corresponding three-phase four-wire AC power supply, and the output terminal of the first current detection unit is connected to the controller 30.

[0105] The first current detection unit is used to detect the phase current of the corresponding phase line of the three-phase four-wire AC power supply. The first current detection unit corresponding to phase A of the three-phase four-wire AC power supply is used to detect the phase current of phase A of the three-phase four-wire AC power supply; the first current detection unit corresponding to phase B of the three-phase four-wire AC power supply is used to detect the phase current of phase B of the three-phase four-wire AC power supply; and the first current detection unit corresponding to phase C of the three-phase four-wire AC power supply is used to detect the phase current of phase C of the three-phase four-wire AC power supply.

[0106] The first current detection unit can be a current transformer, or it can be any other detection unit used to detect the phase current of the phase line in a three-phase four-wire AC power supply. This embodiment does not specifically limit it in this regard.

[0107] In this embodiment, when the three-phase AC power 40 is a three-phase four-wire AC power and the capacitor 10 is a compensation capacitor, the phase voltage of each phase in the three-phase four-wire AC power is collected by the first voltage detection unit, and the phase current of each phase in the three-phase four-wire AC power is collected by the first current detection unit, thus realizing independent monitoring of the phase voltage and phase current of each phase in the three-phase four-wire AC power. By setting up a separate first voltage detection unit and a first current detection unit for each phase of the three-phase AC power 40, the reactive power compensation effect under load imbalance scenarios can be ensured, the risk of overcompensation or undercompensation can be reduced, and the service life of the intelligent capacitor device can be extended.

[0108] In some embodiments, when the three-phase AC power 40 is a three-phase three-wire AC power and the capacitor 10 is a common compensation capacitor, the first voltage detection module 50 includes two second voltage detection units, and the current detection module 60 includes two second current detection units.

[0109] The two second voltage detection units and the two second current detection units correspond one-to-one with the A phase and C phase of the three-phase three-wire AC power.

[0110] It should be noted that the first input terminal of one of the two second voltage detection units is connected to the output terminal of phase A of the three-phase three-wire AC power supply, the second input terminal of the other second voltage detection unit is connected to the output terminal of phase B of the three-phase three-wire AC power supply, and the output terminal of the third second voltage detection unit is connected to the controller 30. Specifically, one second voltage detection unit is used to detect the line voltage U of phase A of the three-phase three-wire AC power supply. AB .

[0111] One of the two second voltage detection units has its first input terminal connected to the output terminal of phase C of the three-phase three-wire AC power supply, its second input terminal connected to the output terminal of phase B of the three-phase three-wire AC power supply, and its output terminal connected to the controller 30. The other second voltage detection unit is used to detect the line voltage U of phase C of the three-phase three-wire AC power supply. BC .

[0112] The structure of the second voltage detection unit is the same as that of the voltage detection unit used for detecting line voltage in the prior art, and will not be described again in this embodiment.

[0113] It should be noted that the input terminal of one of the two second current detection units is connected to the output terminal of phase A of the three-phase three-wire AC power supply, and the output terminal of the other second current detection unit is connected to the controller 30. Specifically, one second current detection unit is used to detect the phase current of phase A of the three-phase three-wire AC power supply.

[0114] The input terminal of one of the two second current detection units is connected to the output terminal of phase C of the three-phase three-wire AC power supply, and the output terminal of the other second current detection unit is connected to the controller 30. The other second current detection unit is used to detect the phase current of phase C of the three-phase three-wire AC power supply.

[0115] The second current detection unit can be a current transformer or other detection unit used to detect the phase current of the phase line of a three-phase three-wire AC power supply. This embodiment does not specifically limit this.

[0116] In this embodiment, utilizing the balance of three-phase three-wire AC power, two second voltage detection units and two second current detection units are set up, with each unit corresponding one-to-one with phase A and phase C of the three-phase three-wire AC power. This achieves accurate detection of the line voltage and phase current of phases A and C of the three-phase three-wire AC power, avoiding redundant detection of phase B and reducing the cost of the intelligent capacitor device. Simultaneously, the controller 30 can determine whether to switch the common compensation capacitor based on the line voltage and phase current data of phases A and C of the three-phase three-wire AC power, ensuring the timeliness and stability of reactive power compensation for the three-phase three-wire AC power.

[0117] like Figure 4 As shown, in some embodiments, the smart capacitor device further includes a second voltage detection module 70.

[0118] The first input terminal of the second voltage detection module 70 is connected to the output terminal of the three-phase AC power 40, the second input terminal of the second voltage detection module 70 is connected to the capacitor 10, and the first and second output terminals of the second voltage detection module 70 are both connected to the controller 30. The second voltage detection module 70 is used to detect the second voltage parameter and the third voltage parameter at both ends of the switch module 22.

[0119] In some embodiments, when the three-phase AC power 40 is a three-phase four-wire AC power and the capacitor 10 is a sub-compensation capacitor, the second voltage detection module 70 includes three third voltage detection units, which correspond one-to-one with phases A, B, and C of the three-phase four-wire AC power; and the three third voltage detection units correspond one-to-one with the three compensation capacitors in the sub-compensation capacitor, and the three third voltage detection units also correspond one-to-one with the three switch modules 22.

[0120] It should be noted that for each third voltage detection unit, the first input terminal of the third voltage detection unit is connected to the output terminal of the phase line of the corresponding three-phase four-wire AC power supply, the second input terminal of the third voltage detection unit is connected to the input terminal of the corresponding compensation capacitor, and the first and second output terminals of the third voltage detection unit are both connected to the controller 30.

[0121] The third voltage detection unit is used to detect the second and third voltage parameters at both ends of its corresponding switch module 22. Since the three-phase four-wire AC power, the switch module 22, and the compensation capacitor are connected in series, when the first input terminal of the third voltage detection unit is connected to the output terminal of the phase line of its corresponding three-phase four-wire AC power, the third voltage detection unit can detect the second voltage parameter at one end of its corresponding switch module 22; when the second output terminal of the third voltage detection unit is connected to the input terminal of its corresponding compensation capacitor, the third voltage detection unit can detect the third voltage parameter at the other end of its corresponding switch module 22, and send the detected second and third voltage parameters to the controller 30, so that the controller 30 can determine the switching state of the compensation capacitor corresponding to each switch module 22 according to the second and third voltage parameters of each switch module 22, and thus determine whether the capacitor 10 is accurately switched when switching the capacitor 10.

[0122] The structure of the third voltage detection unit is the existing structure, and will not be described in detail in this implementation.

[0123] In some other embodiments, when the three-phase AC power 40 is a three-phase three-wire AC power and the capacitor 10 is a common compensation capacitor, the second voltage detection module 70 includes two fourth voltage detection units, which correspond one-to-one with the A phase and C phase of the three-phase three-wire AC power; and the two fourth voltage detection units also correspond one-to-one with the two switch modules 22.

[0124] It should be noted that for each fourth voltage detection unit, the first input terminal of the fourth voltage detection unit is connected to the output terminal of the phase line of the corresponding three-phase three-wire AC power supply, the second input terminal of the fourth voltage detection unit is connected to the input terminal of the corresponding compensation capacitor, and the first and second output terminals of the fourth voltage detection unit are both connected to the controller 30.

[0125] The fourth voltage detection unit is used to detect the second and third voltage parameters at both ends of its corresponding switch module 22. Since the three-phase three-wire AC power, the switch module 22, and the common compensation capacitor are connected in series, when the first input terminal of the fourth voltage detection unit is connected to the output terminal of the phase line of its corresponding three-phase three-wire AC power, the fourth voltage detection unit can detect the second voltage parameter at one end of its corresponding switch module 22; when the second output terminal of the fourth voltage detection unit is connected to the input terminal of its corresponding compensation capacitor, the fourth voltage detection unit can detect the third voltage parameter at the other end of its corresponding switch module 22, and send the detected second and third voltage parameters to the controller 30, so that the controller 30 can determine the switching state of the compensation capacitor corresponding to each switch module 22 according to the second and third voltage parameters of each switch module 22, and thus determine whether the capacitor 10 is accurately switched when switching the capacitor 10.

[0126] The structure of the fourth voltage detection unit is the existing structure, and will not be described in detail in this implementation.

[0127] It should be noted that for any one of the multiple switching modules 22, when the second voltage parameter and the third voltage parameter corresponding to the switching module 22 are equal, the switching module 22 is in a closed state, and the compensation capacitor corresponding to the switching module 22 is in an engaged state; when the second voltage parameter and the third voltage parameter corresponding to the switching module 22 are not equal, the switching module 22 is in a disconnected state, and the compensation capacitor corresponding to the switching module 22 is in a disconnected state.

[0128] In this embodiment, the second voltage detection module 70 detects the second voltage parameters and the third voltage parameters at both ends of the switch module 22, so that the controller 30 can determine the actual switching state of the compensation capacitor corresponding to the switch module 22 in the capacitor 10 based on the second voltage parameters and the third voltage parameters at both ends of the switch module 22, thereby ensuring the effectiveness of reactive power compensation.

[0129] like Figure 4 As shown, in some embodiments, the smart capacitive device further includes a display 80, which is controlled by a controller 30.

[0130] It should be noted that the display 80 is used to display the operating status, parameters and alarm information of the intelligent capacitor device in real time.

[0131] The display 80 is controlled by the controller 30, which sends the received information (first voltage parameter, second voltage parameter, third voltage parameter, current parameter, etc.) to the display 80 for display.

[0132] When the controller 30 detects an abnormal state or requires operation prompts, it can also issue alarm information or display maintenance suggestions through the display 80.

[0133] In other embodiments, the smart capacitive device also includes a button circuit connected to the controller 30, through which various parameters displayed on the display 80 can be switched.

[0134] In this embodiment, by setting a display 80 in the smart capacitor device and having the controller 30 control the information displayed on the display 80 in real time, the operating status of the smart capacitor device is visualized, which can help maintenance personnel understand the operating status of the smart capacitor device more quickly and reduce the risk of misoperation by maintenance personnel.

[0135] like Figure 4 As shown, in some embodiments, the smart capacitor device further includes a communication module 90, one end of which is connected to the controller 30, and the other end of which is connected to the monitoring computer 100.

[0136] It should be noted that the communication module 90 is used to receive data sent by the controller 30 and send the data sent by the controller 30 to the monitoring computer for remote monitoring. In addition, the communication module 90 is also used to transmit the instructions issued by the monitoring computer 100 to the controller 30, so as to realize remote management.

[0137] In this embodiment, the communication module 90 enables data interaction and remote control between the controller 30 and the monitoring computer 100, allowing the operating parameters collected by the controller 30 to be uploaded to the monitoring computer 100 in real time, and supporting the monitoring computer 100 to issue remote commands, thereby improving the reliability and ease of maintenance of the intelligent capacitor device.

[0138] like Figure 4 As shown, in some embodiments, the communication module 90 is an RS485 communication module.

[0139] It should be noted that the RS485 communication module transmits data through two signal lines, A and B, which enhances its resistance to electromagnetic interference and ensures the stability of data transmission. In theory, the RS485 communication module supports a communication distance of up to 1200 meters, making it suitable for remote communication in large industrial sites or distributed systems.

[0140] In this embodiment, an RS485 communication module is used as the communication module of the smart capacitor device, which effectively improves the data transmission stability and communication capability of the smart capacitor device, enabling the smart capacitor device to achieve remote real-time monitoring and centralized management in complex industrial environments, reducing the frequency of manual inspections and improving the reliability of the smart capacitor device.

[0141] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A smart capacitor device, characterized in that, The device includes a capacitor, a switching switch, and a controller: The switching switch includes a drive module and multiple switching modules; Each of the switching modules includes multiple switching units connected in series. The first switching unit connected in series is connected to the output terminal of the three-phase AC power, and the last switching unit connected in series is connected to the capacitor. The control terminals of the multiple switching units are all connected to the output terminal of the drive module, and the input terminal of the drive module is connected to the controller. When the capacitor is disconnected, the controller controls the target switching unit in each switching module to open and the non-target switching unit in each switching module to close via the drive module. When the capacitor is connected, the controller controls the target switch unit in each switch module to close via the drive module, and controls the non-target switch units in each switch module to remain closed. The target switch unit is a switch unit in the switch module whose actual switching count is less than the preset switching count, and the non-target switch unit is any other switch unit in the switch module besides the target switch unit.

2. The intelligent capacitor device according to claim 1, characterized in that, When the three-phase AC power is a three-phase four-wire AC power and the capacitor is a sub-compensator capacitor, the number of the switching modules is three, and the three switching modules correspond one-to-one with phases A, B and C of the three-phase four-wire AC power.

3. The intelligent capacitor device according to claim 1, characterized in that, When the three-phase AC power is a three-phase three-wire AC power and the capacitor is a common compensation capacitor, the number of the switching modules is two, and the two switching modules correspond one-to-one with phase A and phase C of the three-phase three-wire AC power.

4. The intelligent capacitor device according to claim 1, characterized in that, The device further includes a first voltage detection module and a current detection module; The input terminal of the first voltage detection module is connected to the output terminal of the three-phase AC power, and the output terminal of the first voltage detection module is connected to the controller. The first voltage detection module is used to detect the first voltage parameter of the three-phase AC power. The input terminal of the current detection module is connected to the output terminal of the three-phase AC power, and the output terminal of the current detection module is connected to the controller. The current detection module is used to detect the current parameters of the three-phase AC power.

5. The intelligent capacitor device according to claim 4, characterized in that, When the three-phase AC power is a three-phase four-wire AC power and the capacitor is a split capacitor, the first voltage detection module includes three first voltage detection units, and the current detection module includes three first current detection units. The three first voltage detection units and the three first current detection units correspond one-to-one with phases A, B, and C of the three-phase four-wire AC power supply.

6. The intelligent capacitor device according to claim 4, characterized in that, When the three-phase AC power is three-phase three-wire AC power and the capacitor is a common compensation capacitor, the first voltage detection module includes two second voltage detection units, and the current detection module includes two second current detection units. The two second voltage detection units and the two second current detection units correspond one-to-one with the A phase and C phase of the three-phase three-wire AC power.

7. The intelligent capacitor device according to claim 1, characterized in that, The device also includes a second voltage detection module; The first input terminal of the second voltage detection module is connected to the output terminal of the three-phase AC power supply, the second input terminal of the second voltage detection module is connected to the capacitor, and the first and second output terminals of the second voltage detection module are both connected to the controller. The second voltage detection module is used to detect the second voltage parameter and the third voltage parameter at both ends of the switching module.

8. The intelligent capacitor device according to claim 1, characterized in that, The device also includes a display, which is controlled by the controller.

9. The intelligent capacitor device according to claim 1, characterized in that, The device also includes a communication module, one end of which is connected to the controller and the other end of which is connected to a monitoring computer.

10. A smart capacitor device according to claim 9, characterized in that, The communication module is an RS485 communication module.

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