A reactive compensation low-voltage protection box for mine flameproof mobile substation

Abstract

The present invention relates to a reactive compensation low-voltage protection box for a mine-used flameproof mobile substation, comprising an explosion-proof shell, in which a low-voltage protection device and a reactive compensation device are integrated. The low-voltage protection device consists of a low-voltage protection setting button, a low-voltage protection display screen, a test button, a left-side current transformer, a low-voltage protection body, a right-side current transformer, an upper chamber front door body and a low-voltage side integrated protector; the reactive compensation device consists of a zero-sequence current transformer, an AC vacuum contactor, a compensation loop current transformer, a three-phase reactor, a compensation capacitor group, a lower chamber front door body, a compensation loop protector, a reactive compensation controller, a reactive compensation voltage transformer and a control transformer, and can realize automatic reactive compensation of the secondary side power grid of the mine-used flameproof dry-type transformer; the present invention can improve the power grid quality of the mine-used mobile substation, reduce voltage fluctuations, and at the same time reduce the number of on-site equipment and save the usable space in the coal mine tunnel.

Description

[Technical field]

[0001] The invention relates to the technical field of mine mobile substations, in particular to a reactive compensation low-voltage protection box for mine flameproof mobile substations. [Background Technology]

[0002] At present, the mining flameproof mobile substation is used in coal mines with methane mixed gas and coal dust and explosion hazards. As the power distribution device of the comprehensive mechanized mining equipment in coal mines, the main equipment is the mining flameproof dry-type transformer and the high-voltage switch and low-voltage protection box installed at both ends of the transformer.

[0003] In the mine power system, the electrical equipment configured on the secondary side of the mobile substation has the characteristics of high power, long transmission distance and high energy consumption, which often causes the power supply quality of the mobile substation distribution network to decline, that is, the power factor is low and the voltage fluctuation is large.

[0004] The application of reactive power compensation can significantly improve the transmission and distribution performance of power systems. To ensure a balanced voltage under varying grid conditions, installing reactive power compensation devices on the secondary side of dry-type transformers can achieve the following: stabilizing system voltage, reducing transmission losses, and increasing transmission capacity; improving grid efficiency and increasing transient steady-state limits; and reducing damping under interference, enhancing voltage control and stability, damping power fluctuations. [Summary of the invention]

[0005] The purpose of the present invention is to solve the above-mentioned deficiencies and provide a reactive compensation low-voltage protection box for a mine flameproof mobile substation, which improves the quality of the mine mobile substation power grid, reduces voltage fluctuations, and at the same time reduces the number of on-site equipment, saving the use space in the coal mine tunnel.

[0006] In order to achieve the above purpose, a mine flameproof mobile substation reactive compensation low-voltage protection box is designed, including an explosion-proof shell 2, in which a low-voltage protection device and a reactive compensation device are integrated. The low-voltage protection device consists of a low-voltage protection setting button 3, a low-voltage protection display 4, a test button 8, a left current transformer 16, a low-voltage protection body 19, a right current transformer 20, an upper cavity front door body 23 and a low-voltage side integrated protector 24. The low-voltage protection setting button 3, the low-voltage protection display 4 are designed The test button 8 is arranged on the upper front end of the explosion-proof shell 2, the left current transformer 16 and the right current transformer 20 are arranged on the upper rear side of the explosion-proof shell 2 and are arranged symmetrically on the left and right. The low-voltage protection body 19 is arranged on the front side of the upper part of the explosion-proof shell 2. The front of the upper cavity front door body 23 and the low-voltage side integrated protector 24 are provided in front of the low-voltage protection body 19 in the explosion-proof shell 2. The upper cavity front door body 23 is located below the low-voltage side integrated protector 24; the reactive compensation device The device is composed of a zero-sequence current transformer 17, an AC vacuum contactor 25, a compensation circuit current transformer 26, a three-phase reactor 27, a compensation capacitor group 28, a lower cavity front door body 29, a compensation circuit protector 30, a reactive power compensation controller 31, a reactive power compensation voltage transformer 33 and a control transformer 34. The zero-sequence current transformer 17 is located between the left current transformer 16 and the right current transformer 20. The AC vacuum contactor 25, the compensation circuit current transformer 26, the three-phase reactor 27, The compensation capacitor group 28 is arranged in the lower part of the explosion-proof shell 2. The front side of the lower part of the explosion-proof shell 2 is provided with a lower cavity front door body 29, a compensation circuit protector 30, and a reactive compensation controller 31. The reactive compensation controller 31 is connected to the control transformer 34. The compensation circuit current transformer 26 and the reactive compensation voltage transformer 33 are both connected to the compensation circuit protector 30, and the collected signals are transmitted to the compensation circuit protector 30. The compensation circuit protector 30 is connected to the AC vacuum contactor 25 through the protection contact.

[0007] Furthermore, a low-pressure protection chamber 10 is provided in the upper part of the explosion-proof shell 2, and a reactive compensation chamber 11 is provided in the lower part of the explosion-proof shell 2. The low-pressure protection device is installed in the low-pressure protection chamber 10 located in the upper layer, and the reactive compensation device is installed in the reactive compensation chamber 11 located in the lower layer. A left-side wiring chamber 14 and a right-side wiring chamber 22 are respectively provided on the left and right sides of the upper part of the explosion-proof shell 2.

[0008] Furthermore, a left-side cable introduction device 1 is provided on the left side of the front end of the explosion-proof shell 2, and a right-side cable introduction device 5 is provided on the right side of the front end of the explosion-proof shell 2. The front end of the explosion-proof shell 2 adopts a quick-opening door structure, and the quick-opening door is provided with an upper cavity door opening electromechanical lock 9 and a lower layer door opening electromechanical lock 12. The upper cavity door opening electromechanical lock 9 and the lower layer door opening electromechanical lock 12 are arranged on the side of the explosion-proof shell 2, and a transformer docking flange 13 is provided on the rear side of the explosion-proof shell 2.

[0009] Furthermore, the compensation capacitor group 28 of the reactive compensation device is connected in parallel to the secondary side of the mine flameproof dry-type transformer 37 through the wall-penetrating terminal 18, and the primary side of the mine flameproof dry-type transformer 37 is installed with a mine flameproof high-voltage switch 36.

[0010] Furthermore, the reactive power compensation device is connected to the secondary side power grid of the mine flameproof dry-type transformer 37 through the isolating switch 35 and can be completely disconnected from the power grid through the isolating switch 35 .

[0011] Furthermore, the zero-sequence current transformer 17 transmits the signal from the low-voltage protection chamber 10 to the reactive compensation controller 31 in the reactive compensation chamber 11 through the wall-penetrating terminal 18. The reactive compensation controller 31 is connected to the compensation capacitor group 28 through the AC vacuum contactor 25, and selects the switching on and off of the compensation capacitor group 28 by controlling the disconnection of the AC vacuum contactor 25.

[0012] Furthermore, each compensation circuit of the reactive compensation device is equipped with a compensation circuit current transformer 26 and a three-phase reactor 27, and each three-phase reactor 27 is connected to a compensation capacitor group 28. The sampling signal of the reactive compensation device is transmitted to the compensation circuit protector 30 through a wire, and the protection signal is then input into the reactive compensation controller 31 through the compensation circuit protector 30.

[0013] Furthermore, a reactive compensation setting button 6 and a reactive compensation display screen 7 are provided at the lower front end of the explosion-proof shell 2. The left current transformer 16 and the right current transformer 20 are respectively connected to the left terminal 15 and the right terminal 21. The low-voltage side integrated protector 24 is connected to a low-voltage protection voltage transformer 32.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] (1) The present invention integrates a mine-used low-voltage protection box and a reactive power compensation device into an explosion-proof housing, thereby reducing the number of on-site devices and saving space in the coal mine tunnel;

[0016] (2) The application of the reactive power compensation device of the present invention improves the power grid quality on the secondary side of the mining mobile substation and reduces voltage fluctuations;

[0017] (3) Each compensation capacitor bank of the present invention is equipped with an independent voltage and current detection circuit, and is combined with a dedicated protector, thereby achieving faster response and more accurate fault diagnosis;

[0018] (4) The reactive power compensation device of the present invention is equipped with an isolating switch at the line inlet, which can adapt to more complex working conditions and facilitate equipment maintenance;

[0019] In summary, the present invention combines the functions of the low-voltage protection box and the reactive compensation device for the explosion-proof mobile substation for mining, thereby improving the quality of the secondary side power grid of the mobile substation for mining, and solving the problems of low power factor and large voltage fluctuation caused by high power equipment, long transmission distance and high energy consumption under the power grid. It is worthy of promotion and application. [Brief Description of the Drawings]

[0020] Figure 1 It is a front view of the present invention;

[0021] Figure 2 It is a left side view of the present invention;

[0022] Figure 3 yes Figure 1 Middle AA section view;

[0023] Figure 4 yes Figure 3 Middle BB cross-section;

[0024] Figure 5 yes Figure 2 Middle CC section view;

[0025] Figure 6 It is a schematic diagram of the present invention;

[0026] In the figure: 1, left cable entry device 2, explosion-proof housing 3, low voltage protection setting button 4, low voltage protection display 5, right cable entry device 6, reactive compensation setting button 7, reactive compensation display 8, test button 9, upper chamber door electromechanical lock 10, low voltage protection chamber 11, reactive compensation chamber 12, lower door electromechanical lock 13, transformer docking flange 14, left wiring chamber 15, left terminal 16, left current transformer 17, zero sequence current transformer 18, through-wall terminal 19, low voltage protection body 20, Right side current transformer 21, right side terminal 22, right side wiring chamber 23, upper chamber front door body 24, low voltage side integrated protector 25, AC vacuum contactor 26, compensation circuit current transformer 27, three-phase reactor 28, compensation capacitor group 29, lower chamber front door body 30, compensation circuit protector 31, reactive power compensation controller 32, voltage transformer for low voltage protection 33, voltage transformer for reactive power compensation 34, control transformer 35, disconnector 36, mine flameproof high voltage switch 37, mine flameproof dry-type transformer. [Specific implementation method]

[0027] The present invention provides a reactive compensation low-voltage protection box for a mine flameproof mobile substation, comprising an explosion-proof housing 2, wherein a low-voltage protection device and a reactive compensation device are integrated in the explosion-proof housing 2. The low-voltage protection device is composed of a low-voltage protection setting button 3, a low-voltage protection display screen 4, a test button 8, a left-side current transformer 16, a low-voltage protection body 19, a right-side current transformer 20, an upper cavity front door body 23, and a low-voltage side integrated protector 24. The low-voltage protection device can realize secondary side leakage, leakage lockout, short circuit, overload, overvoltage, undervoltage, and phase failure protection of a mine flameproof dry-type transformer 37; the low-voltage protection setting button 3, the low-voltage protection display screen 4, the test button 8, the left-side current transformer 16, the low-voltage protection body 19, the right-side current transformer 20, the upper cavity front door body 23, and the low-voltage side integrated protector 24. The display screen 4 is arranged at the upper front end of the explosion-proof shell 2, the test button 8 is arranged at the upper side of the explosion-proof shell 2, the left current transformer 16 and the right current transformer 20 are arranged at the upper rear side of the explosion-proof shell 2 and are arranged symmetrically on the left and right, the low-voltage protection body 19 is arranged at the upper front side of the explosion-proof shell 2, and the upper cavity front door body 23 and the low-voltage side integrated protector 24 are provided in front of the low-voltage protection body 19 in the explosion-proof shell 2. The upper cavity front door body 23 is located below the low-voltage side integrated protector 24; the reactive compensation device consists of a zero-sequence current transformer 17, an AC vacuum contactor 25, a compensation circuit current transformer 26, and a three-phase reactance The explosion-proof housing 2 is composed of a compensation capacitor group 28, a lower cavity front door body 29, a compensation circuit protector 30, a reactive compensation controller 31, a voltage transformer 33 for reactive compensation and a control transformer 34, which can realize automatic reactive compensation of the secondary side power grid of the mine flameproof dry-type transformer 37; the zero-sequence current transformer 17 is arranged between the left current transformer 16 and the right current transformer 20, the AC vacuum contactor 25, the compensation circuit current transformer 26, the three-phase reactor 27, and the compensation capacitor group 28 are arranged in the lower part of the explosion-proof housing 2, and the lower cavity front door body 29, the compensation circuit 28 and the lower front side of the explosion-proof housing 2 are provided. Protector 30, reactive power compensation controller 31, reactive power compensation controller 31 is connected to control transformer 34, compensation loop current transformer 26 and reactive power compensation voltage transformer 33 are both connected to compensation loop protector 30, and the collected signal is transmitted to compensation loop protector 30, compensation loop protector 30 is connected to AC vacuum contactor 25 through protection contact; by combining mining low-voltage protection box with reactive power compensation device, the quality of secondary side power grid of mining mobile substation is improved, and the problems of low power factor and large voltage fluctuation caused by high power of equipment under the grid, long transmission distance and high energy consumption are solved.

[0028] Among them, a low-voltage protection chamber 10 is provided in the upper part of the explosion-proof shell 2, and a reactive power compensation chamber 11 is provided in the lower part of the explosion-proof shell 2. The low-voltage protection device and related components are installed in the low-voltage protection chamber 10 located in the upper layer, and the reactive power compensation device and related components are installed in the reactive power compensation chamber 11 located in the lower layer. The left and right sides of the upper part of the explosion-proof shell 2 are respectively provided with a left wiring chamber 14 and a right wiring chamber 22. A left cable entry device 1 is provided on the left side of the front end of the explosion-proof shell 2, and a right cable entry device 5 is provided on the right side of the front end of the explosion-proof shell 2. The front end of the explosion-proof shell 2 adopts a quick-opening door structure, and the quick-opening door is provided with an upper chamber door opening electromechanical lock 9 and a lower layer door opening electromechanical lock 12. The upper chamber door opening electromechanical lock 9 and the lower layer door opening electromechanical lock 12 are arranged on the side of the explosion-proof shell 2, and a transformer docking flange 13 is provided on the rear side of the explosion-proof shell 2.

[0029] In the present invention, the reactive power compensation device's compensation capacitor bank 28 is connected in parallel to the secondary side of a flameproof dry-type mining transformer 37 via through-wall terminals 18. Specifically, the main cable connects the compensation capacitor bank 28 in parallel to the secondary side of the flameproof dry-type mining transformer 37 via through-wall terminals 18. A flameproof high-voltage switch 36 is installed on the primary side of the flameproof dry-type mining transformer 37. An isolating switch 35 is installed between the reactive power compensation device and the main circuit, allowing the reactive power compensation device to be completely disconnected from the power grid. Specifically, the reactive power compensation device is connected to the secondary side of the flameproof dry-type mining transformer 37 via isolating switch 35 and can be completely disconnected from the power grid via isolating switch 35. A zero-sequence current transformer 17 transmits signals from the low-voltage protection chamber 10 to the reactive power compensation controller 31 in the reactive power compensation chamber 11 via through-wall terminals 18. The reactive power compensation controller 31 is connected to the compensation capacitor bank 28 via an AC vacuum contactor 25 and selects whether the compensation capacitor bank 28 is connected or disconnected by controlling the AC vacuum contactor 25. Each compensation circuit of the reactive power compensation device is equipped with a compensation circuit current transformer 26 and a three-phase reactor 27. Each three-phase reactor 27 is connected to a compensation capacitor bank 28. The sampling signal is transmitted via wires to the compensation circuit protector 30, and the protection signal is then input into the reactive power compensation controller 31, thereby implementing short circuit, overload, overvoltage, undervoltage, and phase failure protection for each compensation capacitor bank 28. The reactive power compensation setting button 6 and reactive power compensation display screen 7 are located at the lower front end of the explosion-proof housing 2. The left current transformer 16 and the right current transformer 20 are connected to the left terminal 15 and the right terminal 21, respectively. The low-voltage side integrated protector 24 is connected to a low-voltage protection voltage transformer 32.

[0030] The present invention will be further described below in conjunction with the accompanying drawings:

[0031] As attached Figure 1 and attached Figure 2As shown, the explosion-proof shell 2 of the reactive compensation low-voltage protection box for the mine flameproof mobile substation of the present invention includes four parts: an upper low-voltage protection chamber 10, a lower reactive compensation chamber 11, a left wiring chamber 14, and a right wiring chamber 22. The rear side of the explosion-proof shell 2 is a transformer docking flange 13, and the front end adopts a quick-opening door structure. The quick-opening door is composed of an upper chamber door opening electromechanical lock 9 and a lower door opening electromechanical lock 12, thereby ensuring that the front door can only be opened when the main circuit is in the disconnected position; and after the front door is opened, the low-voltage protection box cannot be closed in a normal manner.

[0032] As attached Figure 3 To the attached Figure 5 As shown, the low-voltage protection device-related components are installed in the upper low-voltage protection cavity 10, the reactive compensation device-related components are installed in the lower reactive compensation cavity 11, and the compensation capacitor group 28 is connected in parallel to the secondary side power grid of the mining flameproof dry-type transformer 37 through the through-wall terminal 18.

[0033] As attached Figure 6 As shown, the zero-sequence current transformer 17 transmits the signal from the upper low-voltage protection chamber 10 to the reactive compensation controller 31 in the lower reactive compensation chamber 11 via the through-wall terminal 18, thereby determining the power factor of the power grid. The compensation capacitor bank 28 is then selected for switching on and off based on the setting value of the reactive compensation controller 31 and by controlling the disconnection of the AC vacuum contactor 25. The compensation circuit current transformer 26 and the reactive compensation voltage transformer 33 transmit the collected signal to the compensation circuit protector 30, which is connected to the AC vacuum contactor 25 via a protective contact. In the event of a fault in any compensation circuit, the current compensation capacitor circuit can be quickly disconnected. The reactive compensation device is connected to the secondary power grid of the mining explosion-proof dry-type transformer 37 via an isolating switch 35, allowing the compensation circuit to be completely disconnected from the power grid through operation. This adapts to more complex working environments and facilitates equipment maintenance. The mine flameproof high-voltage switch 36 is installed on the primary side of the mine flameproof dry-type transformer 37, and the mine flameproof mobile substation reactive compensation low-voltage protection box is installed on the secondary side of the mine flameproof dry-type transformer 37. It is compact and occupies little equipment space.

[0034] The present invention is not limited to the above-mentioned embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A reactive power compensation low-voltage protection box for a mine flameproof mobile substation, comprising an explosion-proof housing (2), characterized in that: The explosion-proof housing (2) is integrated with a low-voltage protection device and a reactive power compensation device. The low-voltage protection device is composed of a low-voltage protection setting button (3), a low-voltage protection display screen (4), a test button (8), a left-side current transformer (16), a low-voltage protection body (19), a right-side current transformer (20), an upper cavity front door body (23) and a low-voltage side integrated protector (24). The low-voltage protection setting button (3) and the low-voltage protection display screen (4) are arranged on the front upper part of the explosion-proof housing (2), and the test button (8) is arranged on the side of the explosion-proof housing (2). The left current transformer (16) and the right current transformer (20) are arranged on the rear side of the upper part of the explosion-proof shell (2) and are arranged symmetrically on both sides. The low-voltage protection body (19) is arranged on the front side of the upper part of the explosion-proof shell (2). The front of the low-voltage protection body (19) in the explosion-proof shell (2) is provided with an upper chamber front door body (23) and a low-voltage side integrated protector (24). The upper chamber front door body (23) is located below the low-voltage side integrated protector (24). The reactive power compensation device is composed of a zero-sequence current transformer (17), an AC vacuum contactor (25) and a low-voltage side integrated protector (24). , a compensation circuit current transformer (26), a three-phase reactor (27), a compensation capacitor group (28), a lower cavity front door body (29), a compensation circuit protector (30), a reactive power compensation controller (31), a reactive power compensation voltage transformer (33) and a control transformer (34), wherein the zero-sequence current transformer (17) is arranged between the left current transformer (16) and the right current transformer (20), and the AC vacuum contactor (25), the compensation circuit current transformer (26), the three-phase reactor (27), the compensation capacitor group (28) are arranged The invention is arranged in the lower part of the explosion-proof housing (2); the front side of the lower part of the explosion-proof housing (2) is provided with a lower cavity front door body (29), a compensation circuit protector (30), and a reactive power compensation controller (31); the reactive power compensation controller (31) is connected to a control transformer (34); the compensation circuit current transformer (26) and the reactive power compensation voltage transformer (33) are both connected to the compensation circuit protector (30), and the collected signals are transmitted to the compensation circuit protector (30); the compensation circuit protector (30) is connected to an AC vacuum contactor (25) via a protection contact.

2. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 1, characterized in that: A low-voltage protection chamber (10) is provided in the upper portion of the explosion-proof housing (2), and a reactive power compensation chamber (11) is provided in the lower portion of the explosion-proof housing (2). The low-voltage protection device is installed in the low-voltage protection chamber (10) located in the upper layer, and the reactive power compensation device is installed in the reactive power compensation chamber (11) located in the lower layer. A left wiring chamber (14) and a right wiring chamber (22) are provided on the left and right sides of the upper portion of the explosion-proof housing (2), respectively.

3. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 1, characterized in that: The left side of the front end of the explosion-proof shell (2) is provided with a left cable introduction device (1), and the right side of the front end of the explosion-proof shell (2) is provided with a right cable introduction device (5). The front end of the explosion-proof shell (2) adopts a quick-opening door structure, and the quick-opening door is provided with an upper cavity door opening electromechanical lock (9) and a lower layer door opening electromechanical lock (12). The upper cavity door opening electromechanical lock (9) and the lower layer door opening electromechanical lock (12) are arranged on the side of the explosion-proof shell (2), and the rear side of the explosion-proof shell (2) is provided with a transformer docking flange (13).

4. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 1, characterized in that: The compensation capacitor group (28) of the reactive power compensation device is connected in parallel to the secondary side of a mine flameproof dry-type transformer (37) through a through-wall terminal (18), and a mine flameproof high-voltage switch (36) is installed on the primary side of the mine flameproof dry-type transformer (37).

5. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 4, characterized in that: The reactive power compensation device is connected to the secondary side power grid of the mine flameproof dry-type transformer (37) through the isolating switch (35), and can be completely disconnected from the power grid through the isolating switch (35).

6. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 1, characterized in that: The zero-sequence current transformer (17) transmits a signal from the low-voltage protection chamber (10) to the reactive compensation controller (31) in the reactive compensation chamber (11) through a through-wall terminal (18); the reactive compensation controller (31) is connected to the compensation capacitor group (28) through an AC vacuum contactor (25), and selects the switching on and off of the compensation capacitor group (28) by controlling the disconnection of the AC vacuum contactor (25).

7. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 6, characterized in that: Each compensation circuit of the reactive compensation device is equipped with a compensation circuit current transformer (26) and a three-phase reactor (27), and each three-phase reactor (27) is connected to a compensation capacitor group (28). The sampling signal of the reactive compensation device is transmitted to a compensation circuit protector (30) through a wire, and the protection signal is then input into a reactive compensation controller (31) through the compensation circuit protector (30).

8. The reactive power compensation low-voltage protection box for a mine flameproof mobile substation according to claim 1, characterized in that: The front lower portion of the explosion-proof housing (2) is provided with a reactive compensation setting button (6) and a reactive compensation display screen (7); the left current transformer (16) and the right current transformer (20) are respectively connected to the left terminal (15) and the right terminal (21); and the low-voltage side integrated protector (24) is connected to a low-voltage protection voltage transformer (32).

Images