Grounding system, frequency conversion system and fracturing system

Abstract

The utility model provides a grounding system, a frequency conversion system and a fracturing system.The grounding system is used for being connected with frequency conversion equipment, a first grounding bar of the grounding system is used for being electrically connected with a first device of the frequency conversion equipment, a second grounding bar is used for being electrically connected with a second device, and a third grounding bar is used for being electrically connected with a third device. The third grounding bar, the second grounding bar and the first grounding bar are arranged at intervals and are electrically connected with the grounding electrode; and the grounding system is used for realizing grounding of the first device, the second device and the third device. On the basis, the grounding system can improve the safety performance of the frequency conversion equipment, meanwhile, the grounding system can reduce mutual interference among the three devices in the frequency conversion equipment, and the grounding system can improve the working performance of the frequency conversion equipment.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas field fracturing, and in particular to a grounding system, a frequency conversion system and a fracturing system. Background Art

[0002] Fracturing is a technique used during the oil and gas extraction process to create fractures in oil and gas reservoirs using high-pressure fracturing fluid. This process improves the underground flow of oil or gas and increases well production. Fracturing, as a core technology in shale gas development, is widely used in shale reservoir reconstruction and shale gas extraction.

[0003] Frequency conversion equipment is a key component in fracturing operations. It converts AC power from generators, the power grid, or energy storage batteries at the well site into a voltage- and frequency-controlled AC power source, thereby driving the fracturing equipment's motor and regulating its speed. However, frequency conversion equipment in related technologies can easily generate potentially dangerous voltages and harmonic signal interference during use. Utility Model Content

[0004] The purpose of this application is to provide a grounding system, a frequency conversion system and a fracturing system. The grounding system can reduce the potential dangerous voltage and harmonic signal interference generated by the frequency conversion equipment, and can improve the safety and working performance of the frequency conversion equipment.

[0005] In order to solve the above problems, in a first aspect, the present application provides a grounding system for connecting to a frequency conversion device, wherein the frequency conversion device includes a first device, a second device, and a third device; the grounding system includes:

[0006] a first grounding bar, configured to be electrically connected to the first device;

[0007] a second grounding bar, configured to be electrically connected to the second device; and

[0008] The third grounding bar is used to be electrically connected to the third device; wherein,

[0009] The first grounding bar, the second grounding bar and the third grounding bar are spaced apart from each other and are used to be electrically connected to a grounding electrode to achieve grounding of the first device, the second device and the third device.

[0010] Optionally, the frequency conversion device includes the first device, the second device, and the third device having different functions;

[0011] The first grounding bar is used to implement protective grounding of the first device, the second grounding bar is used to implement protective grounding of the second device, and the third grounding bar is used to implement shielding grounding of the third device.

[0012] Optionally, the first device includes a PE terminal and an N terminal;

[0013] The first grounding bar is used to be electrically connected to the PE terminal and to achieve protective grounding of the first device. The grounding system is not electrically connected to the N terminal.

[0014] Optionally, the first device includes a main transformer and an auxiliary transformer, the main transformer includes a first PE terminal and a first N terminal, and the auxiliary transformer includes a second PE terminal and a second N terminal;

[0015] The grounding system is not electrically connected to the first N terminal and the second N terminal. The first grounding bar is used to be electrically connected to the first PE terminal and the second PE terminal and to achieve protective grounding of the main transformer and the auxiliary transformer.

[0016] Optionally, the grounding system further includes:

[0017] A fourth grounding bar is configured to be electrically connected to the first device and the grounding electrode, and the fourth grounding bar is configured to achieve functional grounding of the first device.

[0018] Optionally, the first device includes a PE terminal and an N terminal;

[0019] The first grounding bar is used to be electrically connected to the PE terminal and used to achieve protective grounding of the first device. The fourth grounding bar is used to be electrically connected to the N terminal and used to achieve functional grounding of the first device.

[0020] Optionally, the first device includes a main transformer and an auxiliary transformer, the main transformer includes a first PE terminal and a first N terminal, and the auxiliary transformer includes a second PE terminal and a second N terminal;

[0021] The first grounding bar is used to be electrically connected to the first PE terminal and the second PE terminal, and is used to achieve protective grounding of the main transformer and the auxiliary transformer; the fourth grounding bar is electrically connected to the first N terminal and the second N terminal, and is used to achieve functional grounding of the main transformer and the auxiliary transformer.

[0022] Optionally, the first grounding bar, the second grounding bar and the third grounding bar are electrically connected to the grounding electrode via grounding wires respectively; or,

[0023] The third grounding bar is electrically connected to the grounding electrode via a grounding wire. The first grounding bar and the second grounding bar are electrically connected to form a whole, and the whole is electrically connected to the grounding electrode via another grounding wire.

[0024] Optionally, the first device includes a transformer unit, and the third device includes a control unit;

[0025] The first grounding bar is used to be electrically connected to the transformer unit and to achieve grounding of the transformer unit; the third grounding bar is used to be electrically connected to the control unit and to achieve grounding of the control unit.

[0026] Optionally, the third device further includes a signal cable;

[0027] The third grounding bar is further used to be electrically connected to the shielding layer of the signal cable. The third grounding bar is used to achieve shielding grounding of the control unit and the signal cable.

[0028] Optionally, the second device includes at least one of a vacuum contactor, a line inlet unit, a water pump, and a heat dissipation unit;

[0029] The second grounding bar is electrically connected to at least one of the vacuum contactor, the incoming line unit, the water pump, and the heat dissipation unit to achieve grounding.

[0030] In a second aspect, the present application further provides a frequency conversion system, comprising:

[0031] A frequency conversion device, comprising a first device, a second device, and a third device; and

[0032] A grounding system includes the grounding system as described above, wherein the grounding system is electrically connected to the first device, the second device, and the third device, and realizes grounding of the first device, the second device, and the third device.

[0033] Optionally, the frequency conversion device is a skid structure.

[0034] Optionally, when the first device includes a main transformer and an auxiliary transformer, and the grounding system does not include a fourth grounding bar, the first grounding bar of the grounding system is electrically connected to the first PE terminal of the main transformer and the second PE terminal of the auxiliary transformer, and the grounding system is not electrically connected to the first N terminal of the main transformer and the second N terminal of the auxiliary transformer; or,

[0035] When the first device includes a main transformer and an auxiliary transformer, and the grounding system includes a fourth grounding bar, the first grounding bar is electrically connected to the first PE terminal of the main transformer and the second PE terminal of the auxiliary transformer, and the fourth grounding bar is electrically connected to the first N terminal of the main transformer and the second N terminal of the auxiliary transformer.

[0036] Optionally, when the third device includes a control unit and a signal cable, the third grounding bar is electrically connected to the control unit and the shielding layer of the signal cable, and realizes grounding of the control unit and the signal cable; and / or,

[0037] When the second device includes at least one of a vacuum contactor, an incoming line unit, a water pump, and a heat dissipation unit, the second grounding bar is electrically connected to at least one of the vacuum contactor, the incoming line unit, the water pump, and the heat dissipation unit to achieve grounding.

[0038] In a third aspect, the present application further provides a fracturing system, comprising:

[0039] Fracturing equipment, including drive motors;

[0040] A frequency conversion device for adjusting the operating voltage and operating frequency of the drive motor; the frequency conversion device includes a first device, a second device and a third device; and

[0041] A grounding system includes the grounding system as described above, wherein the grounding system is electrically connected to the first device, the second device, and the third device, and realizes grounding of the first device, the second device, and the third device.

[0042] Based on the above technical solution, the first grounding bar of the grounding system of the present application is used to electrically connect to the first device of the frequency conversion equipment, the second grounding bar is used to electrically connect to the second device, and the third grounding bar is used to electrically connect to the third device. Therefore, the grounding system of the present application connects the first device to the third device of the frequency conversion equipment to the same grounding electrode through three grounding bars and realizes grounding. On the one hand, the grounding system of the present application can realize the grounding of multiple devices of the frequency conversion equipment, reduce the potential dangerous voltage generated when the frequency conversion equipment is working, and improve the safety of the frequency conversion equipment; on the other hand, the three grounding bars are grounded through the same grounding electrode, which can reduce the number of grounding electrodes, simplify the structure of the grounding system and reduce the layout difficulty of the grounding system; on the other hand, the three grounding bars of the present application are connected one-to-one with the three devices of the frequency conversion equipment. The three devices can be grounded through different grounding bars, and the three devices are not easy to interfere with each other. Therefore, under the action of the grounding system of the present application, the working performance of the frequency conversion equipment is better, and the grounding system of the present application can take into account the safety performance and working performance of the frequency conversion equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] To more clearly illustrate the technical solutions of this application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of this application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0044] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0045] Figure 1 A schematic diagram of the first structure of the grounding system provided in an embodiment of the present application;

[0046] Figure 2 A second structural diagram of the grounding system provided in an embodiment of the present application;

[0047] Figure 3 A first connection diagram of the grounding system provided in an embodiment of the present application;

[0048] Figure 4 A second connection diagram of the grounding system provided in an embodiment of the present application;

[0049] Figure 5 for Figure 4 A schematic diagram of the flow of fault current when a fault occurs in the grounding system shown;

[0050] Figure 6 A third structural diagram of the grounding system provided in an embodiment of the present application;

[0051] Figure 7 A third connection diagram of the grounding system provided in an embodiment of the present application;

[0052] Figure 8 for Figure 7 A schematic diagram of the flow of fault current when a fault occurs in the grounding system shown;

[0053] Figure 9 A fourth connection diagram of the grounding system provided in an embodiment of the present application;

[0054] Figure 10 A fifth connection diagram of the grounding system provided in an embodiment of the present application;

[0055] Figure 11 A schematic structural diagram of a frequency conversion system provided in an embodiment of the present application;

[0056] Figure 12 A schematic diagram of the structure of the frequency conversion device provided in an embodiment of the present application;

[0057] Figure 13 for Figure 12 The schematic diagram of the structure of the frequency conversion device shown is with one side downward;

[0058] Figure 14 for Figure 12 The schematic diagram of the structure of the frequency conversion device shown in another direction;

[0059] Figure 15 A schematic structural diagram of a fracturing system provided in an embodiment of the present application;

[0060] Figure 16 A connection diagram of the fracturing equipment provided in an embodiment of the present application.

[0061] The reference numerals indicate:

[0062] 10. Frequency conversion system; 20. Fracturing system; 100. Grounding system; 200. Frequency conversion equipment; 300. Fracturing equipment; 110. First grounding bar; 120. Second grounding bar; 130. Third grounding bar; 140. Grounding electrode; 150. Fourth grounding bar; 210. First device; 220. Second device; 230. Third device; 310. Drive motor; 320. Transmission structure; 330. Fracturing pump; 211. Main transformer; 212. Auxiliary transformer; 213. Transformer unit; 221. Vacuum contactor; 222. Incoming line unit; 223. Heat dissipation unit; 231. Shielding layer; 232. Control unit; 241. Power unit; 2111. First PE terminal; 2112. First N terminal; 2121. Second PE terminal; 2122. Second N terminal. DETAILED DESCRIPTION

[0063] The following will be combined with the appendix of this application Figure 1 To the attached Figure 16 The present invention clearly and completely describes the technical solutions in this application through the following examples. Obviously, the examples described are only some of the examples in this application, not all of them. All other examples obtained by those skilled in the art based on the examples in this application without creative effort are within the scope of protection of this application.

[0064] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0065] In the field of fracturing technology, grounding systems ensure the reliable and stable operation of variable-frequency equipment. They also limit the contact voltage generated by a malfunction to below a safe level, ensuring operator safety. In related art, multiple units of variable-frequency equipment in fracturing systems are often connected to a common grounding bus via grounding wires, which are then connected to a common grounding electrode. However, this approach easily generates harmonic signals that interfere with each other, affecting the performance of the units.

[0066] Based on the above technical problems, the present application provides a grounding system 100 applied to a frequency conversion device 200. The three grounding buses of the grounding system 100 are respectively electrically connected to the three devices of the frequency conversion device 200 and realize the grounding of the three devices, so that different devices are not easily interfered with each other, and the working performance of the frequency conversion device 200 is better.

[0067] The following is a detailed description with reference to specific embodiments. It should be noted that the embodiments of the present application can be presented in various forms, some of which will be described below.

[0068] Please refer to Figures 1 to 3 , Figure 1 This is a schematic diagram of the first structure of the grounding system 100 provided in an embodiment of the present application. Figure 2 This is a second structural diagram of the grounding system 100 provided in an embodiment of the present application. Figure 3 This is a schematic diagram of a first connection method for a grounding system 100 provided in an embodiment of the present application. The grounding system 100 of the present application is used to connect to a frequency conversion device 200, which includes a first device 210, a second device 220, and a third device 230. The grounding system 100 includes a first grounding bar 110, a second grounding bar 120, and a third grounding bar 130.

[0069] The first grounding bar 110, the second grounding bar 120, and the third grounding bar 130 are spaced apart from each other, with any two of the three grounding bars spaced apart. One end of the first grounding bar 110 is electrically connected to the first device 210, and the other end of the first grounding bar 110 is electrically connected to the grounding electrode 140. The first grounding bar 110 can achieve grounding for the first device 210. One end of the second grounding bar 120 is electrically connected to the second device 220, and the other end of the second grounding bar 120 is electrically connected to the grounding electrode 140. The second grounding bar 120 can achieve grounding for the second device 220. One end of the third grounding bar 130 is electrically connected to the third device 230, and the other end of the third grounding bar 130 is electrically connected to the grounding electrode 140. The third grounding bar 130 can achieve grounding for the third device 230.

[0070] It is understood that the grounding electrode 140 is a structure that is in full contact with the earth and connected to the earth and can introduce current into the earth. The grounding electrode 140 is also called a grounding body. In some examples, such as Figure 1 As shown, the grounding electrode 140 is a structure independent of the grounding system 100. In other examples, such as Figure 2 As shown, the grounding system 100 includes a grounding electrode 140 , wherein the first grounding bar 110 , the second grounding bar 120 , and the third grounding bar 130 of the embodiment of the present application are connected to the same grounding electrode 140 .

[0071] It is understood that a grounding bar is a structure capable of connecting multiple grounding wires, which can connect electrical equipment to a grounding electrode 140 via the grounding wires, providing a low-impedance grounding path. This grounding path can direct fault currents from electrical equipment to the ground, thereby reducing the risk of electric shock to personnel and equipment. In the embodiments of the present application, at least one of the first grounding bar 110, the second grounding bar 120, and the third grounding bar 130 can be, but is not limited to, a copper grounding bar, a magnesium grounding bar, an aluminum grounding bar, a copper-aluminum composite grounding bar, a magnesium-aluminum composite grounding bar, etc. This application does not limit the material of the grounding bar.

[0072] It is understood that in some examples, the first device 210, the second device 220, and the third device 230 of the frequency conversion device 200 are functionally identical devices, or two of the three devices are functionally identical devices. Of course, in other examples, the first device 210, the second device 220, and the third device 230 of the frequency conversion device 200 are functionally distinct devices, each having different functions or uses within the frequency conversion device 200. For example, the first device 210 can adjust the voltage or frequency of an electrical signal, the second device 220 can switch the frequency of an operating current on and off, and the third device 230 can output a control signal. It should be noted that if two devices are of the same type, such as transformers, even if their voltage regulation ranges are different, the two transformers are functionally identical devices and are not functionally distinct devices within the present application. It should be noted that the first device 210 to the third device 230 of the present application can also have other functions, which are not limited in the present embodiments.

[0073] The grounding system 100 of the embodiment of the present application connects the three devices of the frequency converter 200 to the same grounding electrode 140 through three grounding bars to achieve grounding. On the one hand, the grounding system 100 of the present application can achieve grounding of the three devices, reducing the potentially dangerous voltages generated by the three devices of the frequency converter 200 during operation and improving the safety of the frequency converter 200. On the other hand, the three grounding bars are grounded through the same grounding electrode 140, which can reduce the number of grounding electrodes 140, thereby simplifying the structure of the grounding system 100 and reducing the difficulty of its layout. Furthermore, the three grounding bars of the present application are connected one-to-one with the three devices of the frequency converter 200. The three devices can be grounded through different grounding bars, and interference between the three devices is less likely to occur. In particular, when the three grounding bars of the present application are connected one-to-one with the three different types of devices of the frequency converter 200, the three different types of devices can be grounded through different grounding bars. This makes interference between the different types of devices even less likely, and the grounding system 100 of the present application can effectively reduce interference between the three types of devices of the frequency converter 200. Based on this, under the action of the grounding system 100 of the present application, the working performance of the frequency conversion device 200 is better, and the grounding system 100 of the present application can take into account both the safety performance and the working performance of the frequency conversion device 200.

[0074] In some embodiments, the first device 210 of the frequency conversion device 200 includes at least one, for example, two or more, structures; the second device 220 includes at least one, for example, two or more, structures; and the third device 230 includes at least one, for example, two or more, structures. The two or more structures of the first device 210, the two or more structures of the second device 220, or the two or more structures of the third device 230 are connected to the ground electrode 140 via the same grounding bar and grounded. In this case, each grounding bar can connect multiple structures, reducing the use of grounding wires and the difficulty of grounding layout. It also reduces mutual interference between the multiple structures of the first device 210, the multiple structures of the second device 220, or the multiple structures of the third device 230.

[0075] In some embodiments, the first grounding bar 110 can provide protective grounding for the first device 210. In other embodiments, the second grounding bar 120 can provide protective grounding for the second device 220. In still other embodiments, the third grounding bar 130 can provide shielding grounding for the third device 230.

[0076] Protective grounding refers to grounding that is provided to prevent electrical equipment from endangering personal and equipment safety. For example, the first device 210 includes a PE terminal, and the first grounding bar 110 is used to electrically connect to the PE terminal to ground the PE terminal, thereby achieving protective grounding for the first device 210. For another example, the second device 220 includes a housing structure, and the second grounding bar 120 is used to electrically connect to the housing structure to ground the housing structure, thereby achieving protective grounding for the second device 220. Shielded grounding, also known as electromagnetic compatibility grounding, is a grounding method that enables electrical equipment to operate normally in an electromagnetic environment without causing unacceptable electromagnetic interference to other equipment in the environment. For example, the third device 230 includes a shielding structure, and the third grounding bar 130 is used to electrically connect to the shielding structure. The third grounding bar 130 can achieve shielded grounding for at least one third device 230.

[0077] The grounding system 100 of the embodiment of the present application can implement various types of grounding for three devices through three grounding bars. The protective grounding scheme and the shielding grounding scheme can form different grounding paths through different grounding bars. The harmonic signals generated by different grounding paths are not likely to interfere with each other. The grounding system 100 of the present application can improve the operating performance of the frequency conversion device 200.

[0078] Please combine Figures 1 to 3 Please also refer to Figure 4 , Figure 4 A second connection diagram of the grounding system 100 provided in an embodiment of the present application. The first device 210 includes an L terminal (e.g., an L1 terminal, an L2 terminal, and an L3 terminal), a PE terminal, and an N terminal. One end of the first grounding bar 110 of the grounding system 100 is used to electrically connect to the PE terminal, and the other end is used to electrically connect to the grounding electrode 140. The first grounding bar 110 is used to achieve protective grounding of the first device 210; at the same time, the grounding system 100 is not electrically connected to the N terminal. The grounding system 100 of the embodiment of the present application can be an IT grounding system applied to the frequency conversion equipment 200.

[0079] It is understandable that the L terminal is the phase line terminal of the first device 210, the PE terminal is the protective conductor terminal of the first device 210, and the N terminal is the neutral point terminal of the first device 210. In the embodiment of the present application, the frequency conversion device 200 or the grounding system 100 may also include an L phase line and a PE grounding line, one end of the L phase line is electrically connected to the L terminal, and the other end of the L phase line outputs an electrical signal. One end of the PE grounding line is electrically connected to the PE terminal, and the other end of the PE grounding line is connected to the first grounding bar 110. In the embodiment of the present application, the N terminal is not grounded and is separated from the earth. In this case, the grounding system 100 of the present application can be an IT grounding system.

[0080] It is understood that in some embodiments, Figure 4As shown, the frequency conversion device 200 or the grounding system 100 can include an L1 phase line, an L2 phase line, and an L3 phase line. One end of the L1 phase line is electrically connected to the L1 terminal, and the other end outputs an electrical signal. One end of the L2 phase line is electrically connected to the L2 terminal, and the other end outputs an electrical signal. One end of the L3 phase line is electrically connected to the L3 terminal, and the other end outputs an electrical signal. The frequency conversion device 200 or the grounding system 100 can also include an N line and multiple loads. One end of the N line is electrically connected to the N terminal, and the other end of the N line outputs an electrical signal. One of the loads is electrically connected between the L1 phase line and the N line, another load is electrically connected between the L2 phase line and the N line, and yet another load is electrically connected between the L3 phase line and the N line. The grounding system 100 of the present application can be a three-phase IT grounding system.

[0081] Please combine Figure 4 Please also refer to Figure 5 , Figure 5 for Figure 4 A schematic diagram of the flow of fault current when a fault occurs in the grounding system 100 shown. In an IT grounding system, when a fault occurs in the first device 210 of the frequency conversion equipment 200, the current at the L terminal (e.g., L1 terminal) of the first device 210 flows through the equipment housing of the first device 210 and flows into the earth through the PE line of the grounding system 100. The current on the N line returns to the N terminal of the first device 210 through the capacitive load between the N line and the earth, forming a fault loop. Since the fault current flows into the N terminal of the first device 210 through the capacitance to the earth, the fault current is small and generally does not easily trigger the disconnection action of the protection device. The first device 210 can continue to operate with power, thereby improving the power supply reliability of the frequency conversion equipment 200.

[0082] The grounding system 100 of the present embodiment is an IT grounding system for a frequency converter 200. The N terminal of the first device 210 is not connected to the ground. The current flowing through the N terminal is less likely to interfere with the grounding bar and the grounding system 100. Consequently, the frequency converter 200 is less likely to generate interfering harmonic signals during operation, resulting in improved operating performance. Furthermore, the IT grounding system generates a relatively small fault current when a fault occurs, preventing the protective device of the frequency converter 200 from tripping, allowing the frequency converter 200 to continue operating. The IT grounding system of the present application ensures reliable power supply to the frequency converter 200.

[0083] In order to further improve the electrical reliability of the first grounding bar 110, please combine Figure 1 Please also refer to Figure 6 , Figure 6This is a third structural diagram of the grounding system 100 provided in an embodiment of the present application. The grounding system 100 also includes a fourth grounding bar 150, which is used to electrically connect to the first device 210 and the grounding electrode 140. The fourth grounding bar 150 is used to achieve functional grounding of the first device 210. The so-called functional grounding refers to grounding performed to ensure reliable operation of electrical equipment such as the first device 210. For example, the first device 210 includes a transformer, and the neutral point (e.g., N terminal) of the transformer is grounded through the first grounding bar 110 to achieve functional grounding of the transformer.

[0084] In the embodiment of the present application, the first device 210 achieves protective grounding through the first grounding bar 110 and achieves functional grounding through the fourth grounding bar 150. The first device 210 forms grounding schemes with different functions through different grounding paths. The two grounding paths are not easily interfered with. The grounding system 100 of the embodiment of the present application can improve the working performance of the first device 210.

[0085] Please combine Figure 6 Please also refer to Figure 7 , Figure 7 This is a third connection diagram of the grounding system 100 provided in an embodiment of the present application. The first device 210 includes a PE terminal and an N terminal. One end of the first grounding bar 110 of the grounding system 100 is electrically connected to the PE terminal of the first device 210, and the other end is electrically connected to the grounding electrode 140. The first grounding bar 110 is used to provide protective grounding for the first device 210. Simultaneously, one end of the fourth grounding bar 150 is electrically connected to the N terminal of the first device 210, and the other end of the fourth grounding bar 150 is electrically connected to the grounding electrode 140. The fourth grounding bar 150 is used to provide functional grounding for the first device 210. In this case, the grounding system 100 in the embodiment of the present application can be a TN grounding system applied to the frequency conversion device 200.

[0086] It is understandable that if Figure 8 As shown, Figure 8 for Figure 7 The diagram shows a fault current flow diagram when a fault occurs in the grounding system 100. When a fault occurs in the first device 210 and generates a fault current, the current at the L1 port of the first device 210 flows through the housing of the first device 210 and returns to the N terminal of the transformer of the first device 210 via the PE grounding wire, forming a fault loop. The fault current in this fault loop is very large, equivalent to a single-phase short circuit. The extremely large fault current causes the protection device of the frequency converter 200 to react quickly and cut off the power supply, thereby protecting personnel and the first device 210.

[0087] The grounding system 100 of the present embodiment can be a TN grounding system for the frequency conversion device 200. The N terminal of the first device 210 is grounded via the fourth grounding bar 150 and the grounding electrode 140. Grounding the N terminal clamps the voltage at the N point of the first device 210 to zero, thereby ensuring three-phase voltage balance in the grounding system 100 and reducing the risk of voltage imbalance. Furthermore, a TN grounding system generates a large fault current when a fault occurs in the first device 210. This system can prompt the protective device of the frequency conversion device 200 to quickly shut off power, ensuring the safety of the first device 210 and personnel. The TN grounding system of the present application can significantly improve the power supply reliability of the frequency conversion device 200. Furthermore, the first device 210 achieves protective grounding via the first grounding bar 110 and functional grounding via the fourth grounding bar 150. The current at the N terminal of the first device 210 is less likely to interfere with the grounding path of the PE terminal. Therefore, the grounding system 100 of the present embodiment can improve the operating performance of the first device 210.

[0088] It should be noted that, in the embodiment of the present application, a first grounding bar 110 may be provided to achieve functional grounding of the first device 210, and a fourth grounding bar 150 may be provided to achieve protective grounding of the first device 210. The specific solution can be referred to the above description and will not be elaborated here.

[0089] In some embodiments, the first device 210 of the frequency conversion device 200 includes a transformer unit 213 (as shown in the attached figure below). Figures 12 to 14 ), the first grounding bar 110 or the first grounding bar 110 and the fourth grounding bar 150 are electrically connected to the transformer unit 213 and used to ground the transformer unit 213. In some embodiments, the third device 230 includes a control unit 232, and the third grounding bar 130 is electrically connected to the control unit 232 and used to ground the control unit 232. For example, the third grounding bar 130 is used to provide shielding grounding for the control unit 232. In some embodiments, the second device 220 includes a structure having a function or purpose different from that of the transformer unit 213 and the control unit 232. The second grounding bar 120 is electrically connected to the structure and used to ground the structure.

[0090] The grounding system 100 of the embodiment of the present application can form different grounding paths with structures such as the transformer unit 213 and the control unit 232. The harmonic signal generated by the transformer unit 213 during operation is not likely to interfere with the control unit 232. The solution of the present application can ensure the control accuracy of the control unit 232.

[0091] In some embodiments, please refer to Figures 4 to 8The transformer unit 213 of the first device 210 can include a main transformer 211 and an auxiliary transformer 212. The main transformer 211 can convert a received voltage signal into a lower voltage signal. The auxiliary transformer 212 is connected to the main transformer 211 and can further convert the received voltage signal transmitted by the main transformer 211 into an even lower voltage signal. The main transformer 211 includes a first PE terminal 2111 and a first N terminal 2112, and the auxiliary transformer 212 includes a second PE terminal 2121 and a second N terminal 2122. The main transformer 211 and the auxiliary transformer 212 also each include an L terminal, for example, an L1 terminal, an L2 terminal, and an L3 terminal.

[0092] like Figure 4 As shown, in the IT grounding system, the first PE terminal 2111 of the main transformer 211 is connected to the first grounding bar 110 via a grounding wire, and the second PE terminal 2121 of the auxiliary transformer 212 is connected to the first grounding bar 110 via another grounding wire. The first grounding bar 110 can be a transformer grounding bar, and the first grounding bar 110 can achieve protective grounding for the main transformer 211 and the auxiliary transformer 212. Furthermore, the IT grounding system does not include the fourth grounding bar 150, and the first N terminal 2112 of the main transformer 211 and the second N terminal 2122 of the auxiliary transformer 212 are not electrically connected to the grounding system 100.

[0093] like Figure 7 As shown, in a TN grounding system, the first PE terminal 2111 of the main transformer 211 and the second PE terminal 2121 of the auxiliary transformer 212 are both electrically connected to the first grounding bar 110. The first grounding bar 110 serves as the transformer grounding bar and provides protective grounding for the main transformer 211 and the auxiliary transformer 212. Simultaneously, the first N terminal 2112 of the main transformer 211 is connected to the fourth grounding bar 150 via a grounding wire, and the second N terminal 2122 of the auxiliary transformer 212 is also connected to the fourth grounding bar 150 via another grounding wire. The fourth grounding bar 150 can serve as the transformer's N-line grounding bar and provide functional grounding for the main transformer 211 and the auxiliary transformer 212. Consequently, the main transformer 211 and the auxiliary transformer 212 achieve protective grounding through the first grounding bar 110 and functional grounding through the fourth grounding bar 150.

[0094] It is understandable that if Figure 4 and Figure 7As shown, in an IT grounding system or a TN system, the first grounding bar 110 includes at least three grounding posts, the first PE terminal 2111 is connected to one of the grounding posts, such as the grounding post a1, through a grounding wire, the second PE terminal 2121 is connected to another grounding post, such as the grounding post a2, through another grounding wire, and another grounding post, such as the grounding post a3, can be directly or indirectly connected to the grounding electrode 140 through another grounding wire. Figure 7 As shown, in the TN grounding system, the fourth grounding bar 150 also includes at least three grounding posts. The first N terminal 2112 is connected to one of the grounding posts via a grounding wire, and the second N terminal 2122 is connected to another of the grounding posts via another grounding wire. Another of the grounding posts can be directly or indirectly connected to the ground electrode 140 via another grounding wire.

[0095] It should be noted that the number of grounding posts of the first grounding bar 110 and the fourth grounding bar 150 is adaptively set according to the number of structures included in the first device 210; the number of grounding posts of the second grounding bar 120 is adaptively set according to the number of structures included in the second device 220; and the number of grounding posts of the third grounding bar 130 is adaptively set according to the number of structures included in the third device 230.

[0096] In the grounding system 100 of the embodiment of the present application, the first PE terminal 2111 of the main transformer 211 and the second PE terminal 2121 of the auxiliary transformer 212 are connected to the grounding electrode 140 through the same grounding bar. The first PE terminal 2111 and the second PE terminal 2121 are unlikely to interfere with the grounding paths of the second device 220 and the third device 230. Similarly, the first N terminal 2112 of the main transformer 211 and the second N terminal 2122 of the auxiliary transformer 212 are connected to the grounding electrode 140 through the same grounding bar. The first N terminal 2112 and the second N terminal 2122 are unlikely to interfere with the grounding paths of the second device 220 and the third device 230. Therefore, the harmonic signals generated by the operation of the main transformer 211 and the auxiliary transformer 212 are unlikely to affect the second device 220 and the third device 230, and the operating performance of the frequency conversion device 200 is improved.

[0097] It should be noted that the first device 210 of the present application can include the transformer unit 213, or the main transformer 211 and the auxiliary transformer 212, as described in the above embodiment. The first device 210 of the present application can also include other structures. For example, the first device 210 can also include, but is not limited to, a frequency converter. The specific structure of the first device 210 is not limited in the embodiments of the present application.

[0098] In some embodiments, please refer to Figures 4 to 8The second device 220 includes at least one of a vacuum contactor 221, an incoming line unit 222, a water pump (not shown in the drawings), and a heat dissipation unit (e.g., heat dissipation unit 223, described below). The second grounding bar 120 is electrically connected to the housing structure of at least one of the vacuum contactor 221, the incoming line unit 222, the water pump, and the heat dissipation unit 223, and is used to provide protective grounding for the aforementioned devices. For example, the second device 220 includes a vacuum contactor 221 and an incoming line unit 222. The vacuum contactor 221 is electrically connected to the second grounding bar 120 via a grounding wire, and the incoming line unit 222 is electrically connected to the second grounding bar 120 via another grounding wire. The second grounding bar 120 can provide protective grounding for the vacuum contactor 221 and the incoming line unit 222.

[0099] It is understood that the vacuum contactor 221 is a switching device used to control high-voltage circuits. It uses a vacuum environment to isolate the contacts, thereby reducing arcing and improving the reliability of the switch. The incoming line unit 222 is a component in the power system that is responsible for introducing power into the distribution system and ensuring a stable power supply and providing protection in the event of a fault. The incoming line unit 222 usually includes a circuit breaker, a protective device, and a measuring device for controlling and protecting the main power line of the power system. A water pump is a device for moving liquid (usually water) by mechanical force to transport the liquid from one place to another. The heat dissipation unit 223 is used to reduce the temperature of the equipment or space. The heat dissipation unit 223 dissipates heat by blowing air.

[0100] It is understood that the second grounding bar 120 can include multiple grounding posts, and one or more (two or more) of the vacuum contactor 221, the incoming line unit 222, the water pump, and the heat dissipation unit 223 can be connected to a corresponding grounding post via corresponding grounding wires. The second grounding bar 120 can also include at least one grounding post, such as grounding post b1, that is not electrically connected to the second device 220. The second grounding bar 120 can be electrically connected to the ground electrode 140 via this grounding post b1.

[0101] It is understandable that if Figure 4As shown, in an IT grounding system, the third grounding bar 130 can be electrically connected to the grounding electrode 140 via a grounding wire, while the first grounding bar 110 and the second grounding bar 120 are electrically connected as a whole, and this whole is electrically connected to the grounding electrode 140 via a grounding wire. For example, the grounding post a3 of the first grounding bar 110 can be electrically connected to the grounding post b1 of the second grounding bar 120 via a grounding wire, so that the first grounding bar 110 is indirectly connected to the grounding electrode 140 via the second grounding bar 120. In this case, since both the first grounding bar 110 and the second grounding bar 120 can achieve protective grounding, even if they are connected as a whole and then connected to the electrodes, the mutual interference between the grounding currents in the first and second grounding bars 110, 120 is minimal. This connection method of the first and second grounding bars 110, 120 has a minimal impact on the protective grounding paths of the first and second devices 210, 220. Furthermore, the first grounding bar 110 does not need to be electrically connected to the grounding electrode 140 via a long grounding wire, which can reduce the length of the grounding wire and further simplify the structure of the grounding system 100. Similarly, if Figure 6 As shown, in the TN grounding system, the third grounding bar 130 and the fourth grounding bar 150 can be electrically connected to the ground electrode 140 via grounding wires respectively, and the first grounding bar 110 and the second grounding bar 120 can also be electrically connected as a whole, and the whole is electrically connected to the ground electrode 140.

[0102] Of course, in other embodiments, please refer to Figure 9 and Figure 10 , Figure 9 This is a fourth connection diagram of the grounding system 100 provided in an embodiment of the present application. Figure 10 This is a fifth connection diagram of the grounding system 100 provided in the embodiment of the present application. Figure 9 and Figure 10 As shown, in the embodiment of the present application, the first ground bar 110, the second ground bar 120, the third ground bar 130, and the fourth ground bar 150 are electrically connected to the ground electrode 140 via ground wires. In this case, the first ground bar 110, the second ground bar 120, the third ground bar 130, and the fourth ground bar 150 are physically spaced apart from each other, minimizing mutual interference between them.

[0103] The grounding system 100 of the embodiment of the present application connects at least one of the vacuum contactor 221, the incoming line unit 222, the water pump, and the heat dissipation unit 223 to the grounding electrode 140 via the same second grounding bar 120. The vacuum contactor 221, the incoming line unit 222, the water pump, the heat dissipation unit 223, and the like are less likely to interfere with the grounding paths of the first device 210 and the third device 230 having other functions. As a result, the second device 220 is less likely to be affected by harmonic signals generated by the operation of the other devices, and the operating performance of the frequency conversion device 200 is improved.

[0104] Please refer again to Figures 4 to 10 The third device 230 includes a signal cable and a control unit 232. The third grounding bar 130 is used to electrically connect to the shielding layer 231 of the signal cable and achieve grounding of the shielding layer 231 of the signal cable. The third grounding bar 130 is also used to electrically connect to the control unit 232 (e.g., the housing structure of the control unit 232) and achieve shielding grounding of the control unit 232.

[0105] It is understood that the third grounding bar 130 can include at least three grounding posts. The shielding layer 231 of the signal cable can be connected to one of the grounding posts of the third grounding bar 130 via a grounding wire. The control unit 232 can be connected to another grounding post of the third grounding bar 130 via another grounding wire. Another grounding post of the third grounding bar 130 can be electrically connected to the ground electrode 140 via another grounding wire.

[0106] It is understood that the control unit 232 of the third device 230 can include a main control unit and an auxiliary control unit (not shown in the drawings). The main control unit can control the power modules of the frequency converter 200, such as the main transformer 211, the auxiliary transformer 212, and the power unit 241 described below. The auxiliary control unit can control the operation of auxiliary devices, such as the vacuum contactor 221, the incoming line unit 222, the water pump, and the heat dissipation unit 223. The main control unit and the auxiliary control unit can be integrated into the same device and electrically connected to the third grounding bar 130 through their housing structures. Of course, in other embodiments, the main control unit and the auxiliary control unit can also be two independent control devices, and the housing structure of the main control unit can be connected to one grounding post of the third grounding bar 130 via a grounding wire, while the housing structure of the auxiliary control unit can be connected to another grounding post of the third grounding bar 130 via another grounding wire.

[0107] The shielding layer 231 of the signal cable and the outer shell structure of the control unit 232 of the embodiment of the present application realize a shielding structure through the third grounding bar 130. The third grounding bar 130 can transmit the interference signal induced by the shielding layer 231 to the ground, which can not only shield the signal cable of the shielding layer 231, but also prevent the interference signal from interfering with the first device 210 and the second device 220. Therefore, the grounding system 100 of the present application can ensure the working performance of the frequency conversion device 200.

[0108] Based on the above structure, in a TN grounding system, the fourth grounding bar 150 connects to the N-terminals of the three-phase windings of the main transformer 211 and the auxiliary transformer 212 as a loop for the load current. The fourth grounding bar 150 can clamp the voltage at the N-terminal to zero, ensuring three-phase voltage balance and preventing phase voltage imbalance. The second grounding bar 120 connects to the housing structure of the vacuum contactor 221 and the incoming line unit 222. In the event of a fault in the vacuum contactor 221 or the incoming line unit 222, the fault current can be introduced into the grounding electrode 140, maintaining the contact voltage of the vacuum contactor 221 or the incoming line unit 222 below a safe voltage. The third grounding bar 130 connects to devices that require shielding, such as the shielding layer 231 of the signal cable and the housing structure of the control unit 232. The signal grounding bar transmits interference signals induced by the shielding layer 231 to the ground through the grounding bar, shielding the signal cables within the shielding layer 231. First grounding bar 110 is connected to the PE terminals of main transformer 211 and auxiliary transformer 212. When at least one of main transformer 211 and auxiliary transformer 212 fails, the fault current is directed to grounding electrode 140, maintaining the contact voltage of main transformer 211 and auxiliary transformer 212 below a safe voltage. The TN grounding system of this embodiment of the present application can generate a very large fault current in the event of a fault, allowing the protective device of frequency conversion equipment 200 to quickly respond and switch power, thereby protecting personnel and equipment.

[0109] In an IT grounding system, the first grounding bar 110 connects to the PE terminals of the main transformer 211 and the auxiliary transformer 212. When at least one of the main transformer 211 and the auxiliary transformer 212 fails, the fault current is introduced into the grounding electrode 140, maintaining the contact voltage of the main transformer 211 and the auxiliary transformer 212 below a safe voltage. The second grounding bar 120 connects to the housing structure of the vacuum contactor 221 and the incoming line unit 222. When a fault occurs in the vacuum contactor 221 or the incoming line unit 222, the fault current is introduced into the grounding electrode 140, maintaining the contact voltage of the vacuum contactor 221 and the incoming line unit 222 below a safe voltage. The third grounding bar 130 connects to devices that require shielding, such as the shielding layer 231 of the signal cable and the housing structure of the control unit 232. The signal grounding bar transmits interference signals induced by the shielding layer 231 to the ground through the grounding bar, shielding the signal cables within the shielding layer 231. Unlike a TN grounding system, the neutral line of the main transformer 211 and auxiliary transformer 212 in an IT grounding system is separated from the ground. Therefore, there is no interference current in the neutral line in an IT grounding system, resulting in minimal signal interference. Furthermore, the fault current generated by an IT grounding system is relatively small during a fault, preventing the protective device from disconnecting. The inverter 200 can continue to operate, providing improved power supply reliability.

[0110] Based on the structure of the above-mentioned grounding system 100, the embodiment of the present application further provides a frequency conversion system 10. Figure 11 , Figure 11 A schematic structural diagram of a frequency conversion system 10 provided in an embodiment of the present application. The frequency conversion system 10 includes a frequency conversion device 200 and a grounding system 100. The frequency conversion device 200 includes the frequency conversion device 200 of any of the above-mentioned embodiments, and the frequency conversion device 200 includes a first device 210, a second device 220, and a third device 230. The grounding system 100 includes the grounding system 100 of any of the above-mentioned embodiments, and the grounding system 100 includes a first grounding bar 110, a second grounding bar 120, and a third grounding bar 130. The first grounding bar 110 is electrically connected to the first device 210, the second grounding bar 120 is electrically connected to the second device 220, and the third grounding bar 130 is electrically connected to the third device 230. The first grounding bar 110, the second grounding bar 120, and the third grounding bar 130 are all used to electrically connect to a grounding electrode 140, so that the grounding system 100 can achieve grounding of the first device 210, the second device 220, and the third device 230.

[0111] It is understandable that the frequency conversion device 200 of the embodiment of the present application can adopt a container-type cabin to install all components on the cabin, and the frequency conversion device 200 can be set on the cabin. Figures 12 to 14 , Figure 12 A structural diagram of a frequency conversion device 200 provided in an embodiment of the present application is shown in FIG. Figure 13 for Figure 12 The frequency conversion device 200 is shown as a schematic diagram with one side facing downward. Figure 14 for Figure 12 The frequency conversion device 200 is shown as a schematic diagram of the structure in another direction. The frequency conversion device 200 can include the aforementioned transformer unit 213, the incoming line unit 222, the heat dissipation unit 223, the control unit 232, and the power unit 241. The power unit 241 can convert DC signals into AC signals for output to the transformer unit 213. The frequency conversion device 200 can include high-voltage devices, low-voltage devices, and a control system according to the operating voltage. The high-voltage devices include the incoming line unit 222, a phase-shifting transformer (such as the main transformer 211), a control transformer (such as the auxiliary transformer 212), a high-voltage vacuum contactor 221, and a high-power resistor. The low-voltage devices include the heat dissipation unit 223 and a water pump. The control system includes an auxiliary control system for controlling the operation of auxiliary devices (such as the heat dissipation unit 223, the water pump, and other low-voltage devices) and a main control system for controlling the power module (such as the phase-shifting transformer, the control transformer, and other high-voltage devices).

[0112] It is understood that the frequency conversion device 200 of the embodiment of the present application can also adopt a containerized skid structure, and the frequency conversion device 200 can be installed on a mobile transport vehicle. The frequency conversion device 200 has the advantages of compact structure, high protection, and easy transportation. Of course, in other embodiments, the frequency conversion device 200 can also adopt a vehicle-mounted structure, a trailer structure, a fixed structure, etc. The embodiment of the present application does not limit the specific structure of the frequency conversion device 200.

[0113] It is understood that to meet the different operating requirements of the frequency conversion device 200, the design of the grounding system 100 electrically connected to the frequency conversion device 200 may vary. Depending on the requirements of the frequency conversion device 200, this application can select either the IT grounding system or the TN grounding system of any of the aforementioned embodiments. The IT grounding system can operate with faults and ensure reliable power supply to the equipment; the TN grounding system is more sensitive to faults and can quickly cut off power when a line fault occurs to ensure the safety of equipment and personnel.

[0114] The grounding system 100 of the frequency conversion system 10 of the embodiment of the present application connects the three devices of the frequency conversion equipment 200 to the same grounding electrode 140 through three grounding bars and achieves grounding. The grounding system 100 can achieve grounding of the three devices, reduce the potential dangerous voltage generated by the three devices of the frequency conversion equipment 200 during operation, and improve the safety of the frequency conversion equipment 200; at the same time, the three devices can be grounded through different grounding bars, and the harmonic signals generated between different devices are not easy to interfere with each other. Therefore, under the action of the grounding system 100 of the present application, the operating performance of the frequency conversion equipment 200 is better. The grounding system 100 of the present application can take into account both the safety and operating performance of the frequency conversion equipment 200.

[0115] Based on the structure of the above-mentioned grounding system 100, the embodiment of the present application further provides a fracturing system 20. Figure 15 , Figure 15 Schematic diagram of a structure of a fracturing system 20 provided in an embodiment of the present application. The fracturing system 20 includes a fracturing device 300, a frequency conversion device 200 and a grounding system 100.

[0116] Fracturing is a method of creating cracks in oil and gas layers using hydraulic forces during oil or gas production. It is also known as hydraulic fracturing. Fracturing equipment 300 is generally used to pump high-pressure fluid into the well. Figure 16 , Figure 16A connection diagram of the fracturing equipment 300 provided in the embodiment of the present application, the fracturing equipment 300 includes a drive motor 310, a transmission structure 320, a fracturing pump 330 and other structures. The drive motor 310 can be connected to the fracturing pump 330 through the transmission structure 320 and pump high-pressure fluid into the fracturing pump 330. In some embodiments, the fracturing operation can also include a sand mixing device (not shown in the drawings) for mixing the proppant and the fracturing fluid and supplying the fluid to the fracturing equipment 300, and an instrument device (not shown in the drawings) for monitoring the entire equipment group. In the traditional mode, the fracturing equipment 300 is generally a diesel engine driven structure. At this time, the power density of the fracturing equipment 300 is low, the noise is high, and the emission pollution is serious. The fracturing equipment 300 in the embodiment of the present application uses electrical energy as a power source to enable the drive motor 310 to drive the fracturing pump 330. The drive motor 310 has a high power density, low noise, and no exhaust gas emissions, which is more suitable for fracturing operations.

[0117] The frequency conversion device 200 is electrically connected to the fracturing device 300 and is used to adjust the operating voltage and frequency of the drive motor 310 of the fracturing device 300. The frequency conversion device 200 can convert AC power provided by the generator set, power grid, or energy storage battery at the well site during the fracturing operation into AC power with controllable voltage and frequency, and output it to the drive motor 310, thereby rotating the drive motor 310 and adjusting its speed. The frequency conversion device 200 of this embodiment can be any of the frequency conversion devices 200 described above and can include a first device 210, a second device 220, and a third device 230.

[0118] The grounding system 100 is electrically connected to the frequency conversion device 200. The grounding system 100 can be any of the variable grounding systems 100 described above. The grounding system 100 includes a first grounding bar 110, a second grounding bar 120, a third grounding bar 130, and a grounding electrode 140. The first grounding bar 110 is electrically connected to the first device 210, the second grounding bar 120 is electrically connected to the second device 220, and the third grounding bar 130 is electrically connected to the third device 230. The first grounding bar 110, the second grounding bar 120, and the third grounding bar 130 are all electrically connected to the grounding electrode 140. Thus, the grounding system 100 can achieve grounding of the first device 210, the second device 220, and the third device 230.

[0119] In the fracturing system 20 of the embodiment of the present application, the frequency conversion device 200 can convert the AC power provided by the generator set, power grid or energy storage battery of the well site during the fracturing operation into an AC power supply with controllable voltage and frequency and control the speed of the drive motor 310 of the fracturing device 300. Under the action of the grounding system 100, the grounding system 100 can realize the grounding of the three devices of the frequency conversion device 200, which can reduce the potential dangerous voltage generated by the three devices of the frequency conversion device 200 when working and improve the safety of the frequency conversion device 200; at the same time, the three devices of the frequency conversion device 200 can be connected through Different grounding bars are used to achieve grounding, and the harmonic signals generated between different devices are not easy to interfere with each other. Therefore, under the action of the grounding system 100 of the present application, the working performance of the frequency conversion equipment 200 and the fracturing equipment 300 is better. The present application proposes a grounding system 100 for use in the frequency conversion equipment 200 in the oil field, which is designed to address the potential dangerous voltage generated by the mixed use of high and low voltage in the frequency conversion equipment 200 during fracturing operations and to avoid harmonic signal interference with the control system. The grounding system 100 of the present application can take into account the safety and working performance of the frequency conversion equipment 200.

[0120] It should be noted that the grounding system 100, the frequency conversion system 10, and the fracturing system 20 of the embodiments of the present application are different subjects under the same inventive concept. For features not described in detail in each embodiment, please refer to the description of other embodiments. This application will not repeat them again.

[0121] It should be noted that the "multiple" mentioned in this application generally refers to two or more. Moreover, the directional terms mentioned in the embodiments of the present application, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side", etc., are only with reference to the directions of the attached drawings. Therefore, the directional terms used are used to illustrate and understand the embodiments of the present application, rather than to limit the embodiments of the present application. In the various drawings, units with similar structures are represented by the same figure marks. For the sake of clarity, the various parts in the drawings are not drawn to scale. In addition, certain related parts may not be shown in the drawings.

[0122] It should be understood that, in the description of this application, terms such as "first" and "second" are only used to distinguish similar objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0123] It is understood that those skilled in the art can, under the guidance of the above embodiments, combine the various implementations in the above embodiments to obtain technical solutions of multiple implementations. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

[0124] The above describes in detail the grounding system, frequency conversion system, and fracturing system provided by this application. Specific examples are used herein to illustrate the principles and implementation methods of this application. The description of the above embodiments is intended only to facilitate understanding of this application. Furthermore, those skilled in the art will appreciate that variations in the specific implementation methods and scope of application may occur based on the concepts of this application. In summary, this specification should not be construed as limiting this application.

Claims

1. A grounding system, characterized in that: Used to connect with a frequency conversion device, the frequency conversion device includes a first device, a second device and a third device; the grounding system includes: a first grounding bar, configured to be electrically connected to the first device; a second grounding bar, configured to be electrically connected to the second device; and The third grounding bar is used to be electrically connected to the third device; wherein, The first grounding bar, the second grounding bar and the third grounding bar are spaced apart from each other, and are used to be electrically connected to a grounding electrode to achieve grounding of the first device, the second device and the third device.

2. The grounding system according to claim 1, characterized in that The frequency conversion device includes the first device, the second device and the third device having different functions; The first grounding bar is used to implement protective grounding of the first device, the second grounding bar is used to implement protective grounding of the second device, and the third grounding bar is used to implement shielding grounding of the third device.

3. The grounding system according to claim 2, characterized in that: The first device includes a PE terminal and an N terminal; The first grounding bar is used to be electrically connected to the PE terminal and to achieve protective grounding of the first device. The grounding system is not electrically connected to the N terminal.

4. The grounding system according to claim 2, characterized in that: The first device includes a main transformer and an auxiliary transformer, the main transformer includes a first PE terminal and a first N terminal, and the auxiliary transformer includes a second PE terminal and a second N terminal; The grounding system is not electrically connected to the first N terminal and the second N terminal. The first grounding bar is used to be electrically connected to the first PE terminal and the second PE terminal and to achieve protective grounding of the main transformer and the auxiliary transformer.

5. The grounding system according to claim 2, characterized in that: The grounding system further comprises: A fourth grounding bar is configured to be electrically connected to the first device and the grounding electrode, and the fourth grounding bar is configured to achieve functional grounding of the first device.

6. The grounding system according to claim 5, characterized in that: The first device includes a PE terminal and an N terminal; The first grounding bar is used to be electrically connected to the PE terminal and used to achieve protective grounding of the first device. The fourth grounding bar is used to be electrically connected to the N terminal and used to achieve functional grounding of the first device.

7. The grounding system according to claim 5, characterized in that: The first device includes a main transformer and an auxiliary transformer, the main transformer includes a first PE terminal and a first N terminal, and the auxiliary transformer includes a second PE terminal and a second N terminal; The first grounding bar is used to be electrically connected to the first PE terminal and the second PE terminal, and is used to achieve protective grounding of the main transformer and the auxiliary transformer; the fourth grounding bar is electrically connected to the first N terminal and the second N terminal, and is used to achieve functional grounding of the main transformer and the auxiliary transformer.

8. The grounding system according to any one of claims 2 to 7, characterized in that: The first grounding bar, the second grounding bar and the third grounding bar are electrically connected to the grounding electrode through grounding wires respectively; or, The third grounding bar is electrically connected to the grounding electrode via a grounding wire. The first grounding bar and the second grounding bar are electrically connected to form a whole, and the whole is electrically connected to the grounding electrode via another grounding wire.

9. The grounding system according to claim 1, wherein: The first device includes a transformer unit, and the third device includes a control unit; The first grounding bar is used to be electrically connected to the transformer unit and to achieve grounding of the transformer unit; the third grounding bar is used to be electrically connected to the control unit and to achieve grounding of the control unit.

10. The grounding system according to claim 9, characterized in that: The third device further includes a signal cable; The third grounding bar is further used to be electrically connected to the shielding layer of the signal cable. The third grounding bar is used to achieve shielding grounding of the control unit and the signal cable.

11. The grounding system according to any one of claims 1 to 7, 9 to 10, characterized in that: The second device includes at least one of a vacuum contactor, a line inlet unit, a water pump, and a heat dissipation unit; The second grounding bar is electrically connected to at least one of the vacuum contactor, the incoming line unit, the water pump, and the heat dissipation unit to achieve grounding.

12. A frequency conversion system, characterized in that: include: A frequency conversion device, comprising a first device, a second device and a third device; as well as A grounding system, comprising the grounding system according to any one of claims 1 to 11, wherein the grounding system is electrically connected to the first device, the second device, and the third device, and realizes grounding of the first device, the second device, and the third device.

13. The frequency conversion system according to claim 12, characterized in that: The frequency conversion device is a skid structure.

14. The frequency conversion system according to claim 12, characterized in that: When the first device includes a main transformer and an auxiliary transformer, and the grounding system does not include a fourth grounding bar, the first grounding bar of the grounding system is electrically connected to the first PE terminal of the main transformer and the second PE terminal of the auxiliary transformer, and the grounding system is not electrically connected to the first N terminal of the main transformer and the second N terminal of the auxiliary transformer; or When the first device includes a main transformer and an auxiliary transformer, and the grounding system includes a fourth grounding bar, the first grounding bar is electrically connected to the first PE terminal of the main transformer and the second PE terminal of the auxiliary transformer, and the fourth grounding bar is electrically connected to the first N terminal of the main transformer and the second N terminal of the auxiliary transformer.

15. The frequency conversion system according to any one of claims 12 to 14, characterized in that: When the third device includes a control unit and a signal cable, the third grounding bar is electrically connected to the control unit and a shielding layer of the signal cable to achieve grounding of the control unit and the signal cable; and / or, When the second device includes at least one of a vacuum contactor, an incoming line unit, a water pump, and a heat dissipation unit, the second grounding bar is electrically connected to at least one of the vacuum contactor, the incoming line unit, the water pump, and the heat dissipation unit to achieve grounding.

16. A fracturing system, characterized in that: include: Fracturing equipment, including drive motors; A frequency conversion device for adjusting the operating voltage and operating frequency of the drive motor; the frequency conversion device includes a first device, a second device and a third device; as well as A grounding system, comprising the grounding system according to any one of claims 1 to 11, wherein the grounding system is electrically connected to the first device, the second device, and the third device, and realizes grounding of the first device, the second device, and the third device.

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