Totally-enclosed busbar type low-voltage intelligent reactive power compensation device and use method thereof

Abstract

The invention provides a totally-enclosed busbar type low-voltage intelligent reactive power compensation device and a use method, and the device comprises a reactive power compensation cabinet, a wire inlet terminal is installed on one side of the upper end part of the reactive power compensation cabinet, a wire outlet terminal is installed on the other side, a cabinet door is installed on the front side surface of the reactive power compensation cabinet, a display panel is installed on the cabinet door, and walking wheels are installed at the bottom of the reactive power compensation cabinet. A placement plate is installed in an inner cavity of the reactive power compensation cabinet, a low-voltage compensation module is placed on the placement plate, an electric signal collection sensor set and a noise reduction unit are further installed on the inner side of the wire inlet terminal, and a controller is further installed on the inner bottom wall of the reactive power compensation cabinet. The reactive power compensation circuit can compensate reactive power in real time, improve power factors, filter harmonic waves and improve power grid efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of reactive power compensation, and in particular to a fully enclosed busbar type low-voltage intelligent reactive power compensation device and a use method thereof. Background Art

[0002] Low-voltage reactive power compensation device is a kind of free power compensation for low-voltage power grid to improve the power factor of the power grid, reduce line loss and improve the quality of power. The role it plays in the electronic power supply system is to improve the power factor of the power grid, reduce the loss of power supply transformers and transmission lines, improve power supply efficiency and improve the power supply environment. Therefore, reactive power compensation device occupies an indispensable and very important position in the power supply system. Reasonable selection of compensation device can minimize the loss of the network and improve the quality of the power grid.

[0003] At present, the continuous emergence and widespread use of low-voltage reactive power compensation equipment on the market will greatly reduce the quality of power supply: the increase of reactive power loss, the decrease of power factor, the generation of harmonics, these unqualified power transmission will affect the normal operation of users' electrical equipment. In serious cases, it will cause damage to electrical equipment and bring losses to users. Therefore, it is necessary to design a fully enclosed busbar type low-voltage intelligent reactive power compensation device. Summary of the invention

[0004] The present invention provides a fully enclosed busbar type low-voltage intelligent reactive power compensation device and a use method to solve the problem of low reactive power compensation efficiency in the prior art, realizes compensation for the voltage and current of the power grid, can compensate reactive power in real time, improve power factor, filter harmonics, and improve power grid efficiency.

[0005] The present invention provides a fully enclosed busbar type low-voltage intelligent reactive power compensation device, comprising a reactive power compensation cabinet;

[0006] An incoming terminal is installed on one side of the upper end of the reactive compensation cabinet, and an outgoing terminal is installed on the other side. A cabinet door is installed on the front side of the reactive compensation cabinet, a display panel is installed on the cabinet door, and walking wheels are installed on the bottom of the reactive compensation cabinet;

[0007] A placement plate is installed in the inner cavity of the reactive power compensation cabinet, and a low-voltage compensation module is placed on the placement plate;

[0008] An electrical signal acquisition sensor group and a noise reduction unit are also installed on the inner side of the incoming terminal;

[0009] A controller is also installed on the bottom wall of the reactive power compensation cabinet.

[0010] Preferably, the electrical signal acquisition sensor group includes a current transformer and a voltage transformer.

[0011] Preferably, a main control unit, an electrical signal acquisition unit, a reactive power compensation module and an electrical signal transmission unit are installed in the controller, the input end of the electrical signal acquisition unit is respectively connected to a current transformer and a voltage transformer, the output end of the electrical signal acquisition unit is connected to the main control unit through a noise reduction unit, the reactive power compensation module is connected to the main control unit, and the main control unit is connected to a background monitoring terminal through an electrical signal transmission unit; wherein the electrical signal acquisition unit is used for current and voltage signals input from the incoming terminal; and the reactive power compensation module is used for real-time compensation of reactive power and improvement of power factor.

[0012] Preferably, the reactive power compensation module includes three groups of IGBT groups, inductor A, inductor B, and inductor C connected in parallel. The three IGBT groups include a first IGBT group, a second IGBT group, and a third IGBT group. The first IGBT group includes IGBT A, IGBT B, IGBT C, and IGBT D connected in series, and diodes A and B are connected in series between the node between IGBT A and IGBT B and the node between IGBT C and IGBT D; the second IGBT group includes IGBT E, IGBT F, IGBT G, and IGBT H connected in series; diodes C and diodes D are connected in series between the node between IGBT E and IGBT F and the node between IGBT G and IGBT H; the third IGBT group includes IGBTI, IGBT J, IGBT K, and IGBT L connected in series; diodes E and diodes F are connected in series between the node between IGBTI and IGBT J and the node between IGBT K and IGBT L.

[0013] Preferably, the two ends of the IGBT group are also connected in parallel to capacitor A and capacitor B connected in series; one end of the inductor A is connected to the node between IGBT B and IGBT C, and the other end is connected to the A-phase power supply of the power grid; one end of the inductor B is connected to the node between IGBT F and IGBT G, and the other end is connected to the B-phase power supply of the power grid; one end of the inductor C is connected to the node between IGBT J and IGBT K, and the other end is connected to the C-phase power supply of the power grid, and the power grid is also connected to an unbalanced load.

[0014] Preferably, the noise reduction unit includes a transistor, the base of the transistor is respectively connected to one end of a first resistor and one end of a second resistor, the other end of the first resistor is connected to the emitter of the transistor and grounded, the other end of the second resistor is connected to the main control unit, the collector of the transistor is respectively connected to the signal output end and one end of a third resistor, the other end of the third resistor is respectively connected to the VCC end and one end of a capacitor, and the other end of the capacitor is grounded.

[0015] Preferably, the electrical signal transmission unit includes a ZigBee gateway body, the ZigBee gateway body includes a ZigBee module, a gateway main control module, an Ethernet unit and a radio frequency antenna, the gateway main control module is respectively connected to the ZigBee module and the Ethernet unit, and the ZigBee module is connected to the radio frequency antenna.

[0016] Preferably, a method for using a fully enclosed busbar type low-voltage intelligent reactive power compensation device comprises the following steps:

[0017] A. Connect the reactive power compensation cabinet to the power grid, and use the current transformer and voltage transformer to collect the current and voltage signals at the input end of the power grid respectively;

[0018] B. The collected current and voltage signals are de-noised by a noise reduction unit to filter out the interference caused by abnormal fluctuations in the electrical signals;

[0019] C. The current and voltage signals after noise reduction are input into the main control unit;

[0020] D. The main control unit detects the subharmonic voltage and calculates the subharmonic current based on the subharmonic voltage;

[0021] E. The reactive power compensation module performs reactive power compensation based on subharmonic voltage and current;

[0022] F. Finally, the main control unit outputs the power signal after reactive power compensation to the background monitoring terminal.

[0023] Beneficial effects:

[0024] (1) The present invention has a simple working principle and can compensate for the voltage and current of the power grid. It can compensate for reactive power in real time, improve power factor, filter out harmonics, and improve power grid efficiency.

[0025] (2) The reactive power compensation module used in the present invention has excellent reactive power compensation performance, can improve the power factor, overcome three-phase imbalance, and eliminate voltage flicker and voltage fluctuation.

[0026] (3) The noise reduction unit used in the present invention has strong anti-interference capability and can filter out interference caused by abnormal fluctuations in electrical signals.

[0027] (4) The electrical signal transmission unit used in the present invention has strong anti-interference capability, fast signal transmission rate and high efficiency, thereby improving the background monitoring efficiency.

[0028] The above description is only an overview of the technical solution of the embodiment of the present invention. In order to more clearly understand the technical means of the embodiment of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the interior of the reactive power compensation cabinet of the present invention;

[0032] Figure 3 This is a control principle block diagram of the present invention;

[0033] Figure 4 This is a schematic diagram of the reactive power compensation module of the present invention;

[0034] Figure 5 This is a schematic diagram of the noise reduction unit structure of the present invention;

[0035] Figure 6 This is a principle block diagram of the electrical signal transmission unit of the present invention;

[0036] Explanation of the accompanying drawings: reactive power compensation cabinet 1, incoming terminal 2, outgoing terminal 3, cabinet door 4, display panel 5, walking wheel 6, placement board 7, low voltage compensation module 8, noise reduction unit 9, controller 10, current transformer 11, voltage transformer 12, main control unit 13, electrical signal acquisition unit 14, power grid 15, unbalanced load 16, reactive power compensation module 18, electrical signal transmission unit 19, background monitoring terminal 20, transistor 21, first resistor 22, second resistor 23, third resistor 24, capacitor 25, ZigBee module 26, gateway main control module 27, Ethernet unit 28, radio frequency antenna 29. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification, claims and accompanying drawings of the present invention are intended to cover non-exclusive inclusions.

[0039] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase "embodiments" in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive of other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0040] The directional words appearing in the following description are all directions shown in the drawings, and do not limit the specific structure of the present invention. For example, in the description of the present invention, the directions or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention.

[0041] In addition, the expressions of indicated directions such as the X direction, the Y direction, and the Z direction used to illustrate the operation and construction of the components of the present embodiment are not absolute but relative, and although these indications are appropriate when the components are in the positions shown in the figures, when these positions change, these directions should be interpreted differently to correspond to the changes.

[0042] In addition, the terms "first", "second", etc. in the description and claims of the present invention or the above-mentioned 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.

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, the "connection" or "connection" of a mechanical structure may refer to a physical connection. For example, the physical connection may be a fixed connection, such as a fixed connection through a fixing member, such as a fixed connection through a screw, bolt or other fixing member; the physical connection may also be a detachable connection, such as a mutual snap-on or snap-fit ​​connection; the physical connection may also be an integral connection, such as a connection formed by welding, bonding or integral molding. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0045] Embodiment 1:

[0046] See also Figure 1-Figure 5 A fully enclosed busbar type low-voltage intelligent reactive power compensation device, comprising a reactive power compensation cabinet 1;

[0047] An incoming terminal 2 is installed on one side of the upper end of the reactive compensation cabinet 1, and an outgoing terminal 3 is installed on the other side. A cabinet door 4 is installed on the front side of the reactive compensation cabinet 1, and a display panel 5 is installed on the cabinet door 4. A walking wheel 6 is installed at the bottom of the reactive compensation cabinet 1;

[0048] A placement plate 7 is installed in the inner cavity of the reactive power compensation cabinet 1, and a low-voltage compensation module 8 is placed on the placement plate 7;

[0049] The inner side of the incoming terminal 2 is also equipped with an electric signal acquisition sensor group and a noise reduction unit 9;

[0050] A controller 10 is also installed on the inner bottom wall of the reactive power compensation cabinet 1 .

[0051] In the present invention, the electrical signal acquisition sensor group includes a current transformer 11 and a voltage transformer 12 .

[0052] In the present invention, a main control unit 13, an electrical signal acquisition unit 14, a reactive power compensation module 18 and an electrical signal transmission unit 19 are installed in the controller 10, the input end of the electrical signal acquisition unit 14 is respectively connected to the current transformer 11 and the voltage transformer 12, the output end of the electrical signal acquisition unit 14 is connected to the main control unit 13 through the noise reduction unit 9, the reactive power compensation module 18 is connected to the main control unit 13, and the main control unit 13 is connected to the background monitoring terminal 20 through the electrical signal transmission unit 19; wherein the electrical signal acquisition unit is used for the current and voltage signals input by the incoming terminal; the reactive power compensation module is used for real-time compensation of reactive power and improvement of power factor.

[0053] The reactive power compensation module includes three groups of IGBT groups connected in parallel, an inductor A1a, an inductor B2a, and an inductor C3a. The three IGBT groups include a first IGBT group, a second IGBT group, and a third IGBT group. The first IGBT group includes IGBT A1b, IGBT B2b, IGBT C3b, and IGBT D4b connected in series. A diode A1c and a diode B2c are connected in series between the node between IGBT A1b and IGBT B2b and the node between IGBT C3b and IGBT D4b. The second IGBT group includes IGBT E5b, IGBT F6b, IGBT G7b, and IGBT H8b connected in series. A diode C3c and a diode D4c are connected in series between the node between IGBT E5b and IGBT F6b and the node between IGBT G7b and IGBT H8b. The third IGBT group includes IGBT I9b, IGBT J10b, IGBT K11b, and IGBT L12b connected in series. The IGBT I9b and IGBT A diode E5c and a diode F6c connected in series are connected between the node between J10b and the node between IGBT K11b and IGBT L12b; the two ends of the IGBT group are also connected in parallel with the capacitor A1d and the capacitor B2d connected in series; one end of the inductor A1a is connected to the node between IGBT B2b and IGBT C3b, and the other end is connected to the power supply of the power grid 15A phase; one end of the inductor B2a is connected to the node between IGBT F6b and IGBT G7b, and the other end is connected to the power supply of the power grid 15B phase; one end of the inductor C3a is connected to the node between IGBT J10b and IGBT K11b, and the other end is connected to the power supply of the power grid 15C phase, and the power grid 15 is also connected to the unbalanced load 16. The system current is detected in real time through an external current transformer, and the system current information is sent to the internal processor for analysis and processing, the system unbalanced current is calculated, and the current value required to be converted for each phase when the balanced state is reached is calculated, and then the command signal is sent to the internal converter to drive its action, and the output is evenly distributed to the three-phase line, and finally the three-phase load balance state is reached. The reactive power compensation module adopted in the present invention has excellent reactive power compensation performance, can improve the power factor, overcome the three-phase imbalance, and eliminate voltage flicker and voltage fluctuation.

[0054] In the present invention, the noise reduction unit 9 includes a transistor 21, the base of the transistor 21 is respectively connected to one end of the first resistor 22 and one end of the second resistor 23, the other end of the first resistor 22 is connected to the emitter of the transistor 21 and grounded, the other end of the second resistor 23 is connected to the main control unit 13, the collector of the transistor 21 is respectively connected to the signal output end and one end of the third resistor 24, the other end of the third resistor 24 is respectively connected to the VCC end and one end of the capacitor 25, and the other end of the capacitor 25 is grounded. The noise reduction unit used in the present invention has strong anti-interference ability and can filter out interference caused by abnormal fluctuations in electrical signals.

[0055] Embodiment 2:

[0056] See also Figure 1-Figure 6 , a fully enclosed busbar type low-voltage intelligent reactive power compensation device, comprising a reactive power compensation cabinet 1;

[0057] An incoming terminal 2 is installed on one side of the upper end of the reactive compensation cabinet 1, and an outgoing terminal 3 is installed on the other side. A cabinet door 4 is installed on the front side of the reactive compensation cabinet 1, and a display panel 5 is installed on the cabinet door 4. A walking wheel 6 is installed at the bottom of the reactive compensation cabinet 1;

[0058] A placement plate 7 is installed in the inner cavity of the reactive power compensation cabinet 1, and a low-voltage compensation module 8 is placed on the placement plate 7;

[0059] The electric signal acquisition sensor group 10 and the noise reduction unit 9 are also installed inside the incoming terminal 2;

[0060] A controller 10 is also installed on the inner bottom wall of the reactive power compensation cabinet 1 .

[0061] In the present invention, the electrical signal acquisition sensor group includes a current transformer 11 and a voltage transformer 12 .

[0062] In the present invention, a main control unit 13, an electrical signal acquisition unit 14, a reactive power compensation module 18 and an electrical signal transmission unit 19 are installed in the controller 10, the input end of the electrical signal acquisition unit 14 is respectively connected to the current transformer 11 and the voltage transformer 12, the output end of the electrical signal acquisition unit 14 is connected to the main control unit 13 through the noise reduction unit 9, the reactive power compensation module 18 is connected to the main control unit 13, and the main control unit 13 is connected to the background monitoring terminal 20 through the electrical signal transmission unit 19; wherein the electrical signal acquisition unit is used for the current and voltage signals input by the incoming terminal; the reactive power compensation module is used for real-time compensation of reactive power and improvement of power factor.

[0063] The reactive power compensation module includes three groups of IGBT groups connected in parallel, an inductor A1a, an inductor B2a, and an inductor C3a. The three IGBT groups include a first IGBT group, a second IGBT group, and a third IGBT group. The first IGBT group includes IGBT A1b, IGBT B2b, IGBT C3b, and IGBT D4b connected in series. A diode A1c and a diode B2c are connected in series between the node between IGBT A1b and IGBT B2b and the node between IGBT C3b and IGBT D4b. The second IGBT group includes IGBT E5b, IGBT F6b, IGBT G7b, and IGBT H8b connected in series. A diode C3c and a diode D4c are connected in series between the node between IGBT E5b and IGBT F6b and the node between IGBT G7b and IGBT H8b. The third IGBT group includes IGBT I9b, IGBT J10b, IGBT K11b, and IGBT L12b connected in series. The IGBT I9b and IGBT A diode E5c and a diode F6c connected in series are connected between the node between J10b and the node between IGBT K11b and IGBT L12b; the two ends of the IGBT group are also connected in parallel with the capacitor A1d and the capacitor B2d connected in series; one end of the inductor A1a is connected to the node between IGBT B2b and IGBT C3b, and the other end is connected to the power supply of the power grid 15A phase; one end of the inductor B2a is connected to the node between IGBT F6b and IGBT G7b, and the other end is connected to the power supply of the power grid 15B phase; one end of the inductor C3a is connected to the node between IGBT J10b and IGBT K11b, and the other end is connected to the power supply of the power grid 15C phase, and the power grid 15 is also connected to the unbalanced load 16. The system current is detected in real time through an external current transformer, and the system current information is sent to the internal processor for analysis and processing, the system unbalanced current is calculated, and the current value required to be converted for each phase when the balanced state is reached is calculated, and then the command signal is sent to the internal converter to drive it to operate, and the output is evenly distributed to the three-phase line, and finally the three-phase load balance state is reached. The reactive power compensation module adopted in the present invention has excellent reactive power compensation performance, can improve the power factor, overcome the three-phase imbalance, and eliminate voltage flicker and voltage fluctuation.

[0064] In the present invention, the noise reduction unit 9 includes a transistor 21, the base of the transistor 21 is respectively connected to one end of the first resistor 22 and one end of the second resistor 23, the other end of the first resistor 22 is connected to the emitter of the transistor 21 and grounded, the other end of the second resistor 23 is connected to the main control unit 13, the collector of the transistor 21 is respectively connected to the signal output end and one end of the third resistor 24, the other end of the third resistor 24 is respectively connected to the VCC end and one end of the capacitor 25, and the other end of the capacitor 25 is grounded. The noise reduction unit used in the present invention has strong anti-interference ability and can filter out interference caused by abnormal fluctuations in electrical signals.

[0065] In this embodiment, the electric signal transmission unit includes a ZigBee gateway body, and the ZigBee gateway body includes a ZigBee module 26, a gateway main control module 27, an Ethernet unit 28 and a radio frequency antenna 29. The gateway main control module 27 is respectively connected to the ZigBee module 26 and the Ethernet unit 28, and the ZigBee module 26 is connected to the radio frequency antenna 29. The electric signal transmission unit used in the present invention has strong anti-interference ability, fast signal transmission rate and high efficiency, thereby improving the background monitoring efficiency.

[0066] Working principle: A method for using a fully enclosed busbar type low-voltage intelligent reactive power compensation device includes the following steps:

[0067] A. Connect the reactive power compensation cabinet to the power grid, and use the current transformer and voltage transformer to collect the current and voltage signals at the input end of the power grid respectively;

[0068] B. The collected current and voltage signals are de-noised by a noise reduction unit to filter out the interference caused by abnormal fluctuations in the electrical signals;

[0069] C. The current and voltage signals after noise reduction are input into the main control unit;

[0070] D. The main control unit detects the subharmonic voltage and calculates the subharmonic current based on the subharmonic voltage;

[0071] E. The reactive power compensation module performs reactive power compensation based on subharmonic voltage and current;

[0072] F. Finally, the main control unit outputs the power signal after reactive power compensation to the background monitoring terminal.

[0073] In summary, the present invention has a simple working principle and can compensate for the voltage and current of the power grid. It can compensate for reactive power in real time, improve the power factor, filter out harmonics, and improve the efficiency of the power grid.

[0074] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fully enclosed busbar type low-voltage intelligent reactive power compensation device, characterized in that: It comprises a reactive power compensation cabinet (1); An incoming terminal (2) is installed on one side of the upper end of the reactive compensation cabinet (1), and an outgoing terminal (3) is installed on the other side; a cabinet door (4) is installed on the front side of the reactive compensation cabinet (1); a display panel (5) is installed on the cabinet door (4); and walking wheels (6) are installed on the bottom of the reactive compensation cabinet (1); A placement plate (7) is installed in the inner cavity of the reactive power compensation cabinet (1), and a low-voltage compensation module (8) is placed on the placement plate (7); An electrical signal acquisition sensor group and a noise reduction unit (9) are also installed on the inner side of the incoming terminal (2); A controller (10) is also installed on the inner bottom wall of the reactive power compensation cabinet (1).

2. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 1, characterized in that: The electrical signal acquisition sensor group comprises a current transformer (11) and a voltage transformer (12).

3. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 2, characterized in that: The controller (10) is installed with a main control unit (13), an electric signal acquisition unit (14), a reactive power compensation module (18) and an electric signal transmission unit (19); the input end of the electric signal acquisition unit (14) is respectively connected to a current transformer (11) and a voltage transformer (12); the output end of the electric signal acquisition unit (14) is connected to the main control unit (13) via a noise reduction unit (9); the reactive power compensation module (18) is connected to the main control unit (13); and the main control unit (13) is connected to a background monitoring terminal (20) via the electric signal transmission unit (19); wherein the electric signal acquisition unit is used for current and voltage signals inputted from the incoming terminal; and the reactive power compensation module is used for real-time compensation of reactive power to improve the power factor.

4. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 1, characterized in that: The reactive power compensation module comprises three groups of IGBT groups connected in parallel, an inductor A (1a), an inductor B (2a), and an inductor C (3a). The three IGBT groups comprise a first IGBT group, a second IGBT group, and a third IGBT group. The first IGBT group comprises IGBT A (1b), IGBT B (2b), IGBT C (3b), and IGBT D (4b) connected in series. A diode A (1c) and a diode B (2c) connected in series are connected between a node between the IGBT A (1b) and IGBT B (2b) and a node between the IGBT C (3b) and IGBT D (4b). The second IGBT group comprises IGBT E (5b), IGBT F (6b), IGBT G (7b), and IGBT H (8b) connected in series. The node between the IGBT E (5b) and IGBT F (6b) and the node between the IGBT G (7b) and IGBT D (4b) are connected in series. A diode C (3c) and a diode D (4c) connected in series are connected between the node between IGBT (9b), IGBT J (10b), IGBT K (11b), and IGBT L (12b) connected in series; a diode E (5c) and a diode F (6c) connected in series are connected between the node between IGBT (9b) and IGBT J (10b) and the node between IGBT K (11b) and IGBT L (12b).

5. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 4, characterized in that: The two ends of the IGBT group are also connected in parallel to capacitors A (1d) and B (2d) connected in series; one end of the inductor A (1a) is connected to a node between IGBT B (2b) and IGBT C (3b), and the other end is connected to an A-phase power supply of a power grid (15); one end of the inductor B (2a) is connected to a node between IGBT F (6b) and IGBT G (7b), and the other end is connected to a B-phase power supply of a power grid (15); one end of the inductor C (3a) is connected to a node between IGBT J (10b) and IGBT K (11b), and the other end is connected to a C-phase power supply of a power grid (15); the power grid (15) is also connected to an unbalanced load (16).

6. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 1, characterized in that: The noise reduction unit (9) comprises a triode (21), the base of the triode (21) being respectively connected to one end of a first resistor (22) and one end of a second resistor (23), the other end of the first resistor (22) being connected to the emitter of the triode (21) and being grounded, the other end of the second resistor (23) being connected to the main control unit (13), the collector of the triode (21) being respectively connected to a signal output end and one end of a third resistor (24), the other end of the third resistor (24) being respectively connected to a VCC end and one end of a capacitor (25), and the other end of the capacitor (25) being grounded.

7. A fully enclosed busbar type low-voltage intelligent reactive power compensation device according to claim 3, characterized in that: The electrical signal transmission unit comprises a ZigBee gateway body, the ZigBee gateway body comprises a ZigBee module (26), a gateway main control module (27), an Ethernet unit (28) and a radio frequency antenna (29), the gateway main control module (27) is respectively connected to the ZigBee module (26) and the Ethernet unit (28), and the ZigBee module (26) is connected to the radio frequency antenna (29).

8. A method for using a fully enclosed busbar type low-voltage intelligent reactive power compensation device as claimed in claim 1, characterized in that: The method of use includes the following steps: A. Connect the reactive power compensation cabinet to the power grid, and use the current transformer and voltage transformer to collect the current and voltage signals at the input end of the power grid respectively; B. The collected current and voltage signals are de-noised by a noise reduction unit to filter out the interference caused by abnormal fluctuations in the electrical signals; C. The current and voltage signals after noise reduction are input into the main control unit; D. The main control unit detects the subharmonic voltage and calculates the subharmonic current based on the subharmonic voltage; E. The reactive power compensation module performs reactive power compensation based on subharmonic voltage and current; F. Finally, the main control unit outputs the power signal after reactive power compensation to the background monitoring terminal.

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