All-insulation wire inlet structure of boost substation

Abstract

The utility model discloses an all-insulation wire inlet structure of a boost substation, and belongs to the technical field of high-voltage equipment. The utility model relates to a voltage boosting device, which is suitable for a transformer station for boosting 35kV or 66kV current to 110kV or 220kV and comprises a low-voltage section, and the current in the low-voltage section flows into a first switch power distribution cabinet, a GIL input line, a first gas insulated metal closed switch and a GIL input line through power generation equipment and finally enters a boosting transformer; and the current in the high-voltage section is boosted by a boosting transformer, then enters a second switch power distribution cabinet through a GIL output line, a second gas insulated metal-enclosed switch and a GIL output line in sequence, and finally flows into the power grid, and the insulating gas in the line is SF6. Compared with a conventional transformer substation wire inlet mode, the all-insulation wire inlet structure of the boost transformer substation provided by the utility model has the advantages that the requirement on the insulation distance of equipment is low, the boundary dimension and the occupied space of the equipment can be reduced, and the whole line of the wire inlet structure is free of exposed electrified bodies, is slightly influenced by external factors and is safer.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage equipment, and more specifically to a fully insulated incoming line structure of a boosting substation. Background Art

[0002] At present, most substations use overhead lines for incoming lines. Some step-down substations use a fully insulated structure with GIS (gas-insulated metal-enclosed switchgear) directly connected to the transformer for high-voltage incoming lines, while step-up substations still use an overhead line plus isolating switch structure.

[0003] For the current step-up substations that use overhead lines, the following problems still need to be solved in actual application:

[0004] 1) The overhead line incoming to the step-up substation is easily affected by external environmental factors such as humidity and altitude. During operation, since the incoming line is exposed, it is necessary to maintain a safe distance in accordance with the regulations of the corresponding voltage level. To ensure the safety of the insulation distance, a large area is generally required, wasting a lot of resources.

[0005] 2) It is difficult to connect the pressurized test tooling to conduct the pressurized test.

[0006] 3) At the same time, there are many live parts in the power station incoming lines, and the booster substation using overhead lines has low safety and is prone to safety accidents. Utility Model Content

[0007] In order to overcome the problems raised in the above background technology, the utility model provides a fully insulated incoming line structure for a step-up substation.

[0008] In order to solve the above technical problems, the technical solutions of the present utility model are as follows:

[0009] A fully insulated incoming line structure for a step-up substation, comprising:

[0010] A low-voltage section, in which the current flows through the power generation equipment into the first switch distribution cabinet, the GIL input line, the first gas-insulated metal-enclosed switch, the GIL input line, and finally into the step-up transformer;

[0011] The high-voltage section, after being boosted by the boost transformer, the current in the high-voltage section passes through the GIL output line, the second gas-insulated metal-enclosed switch, the GIL output line in sequence and enters the second switch distribution cabinet, and finally flows into the power grid.

[0012] Preferably, the voltage in the low-voltage section is 35 kV; the voltage in the high-voltage section is 110 kV or 220 kV.

[0013] Preferably, the insulating gas in the GIL input line and the GIL output line is SF6.

[0014] Preferably, the first gas-insulated metal-enclosed switch and the second gas-insulated metal-enclosed switch each include a circuit breaker, a grounding switch and a voltage transformer, wherein:

[0015] Circuit breakers are used to disconnect circuits;

[0016] The grounding switch is used for equipment maintenance;

[0017] Voltage transformers are used for equipment monitoring.

[0018] Preferably, the GIL input line and the GIL output line are both connected to the step-up transformer via a three-position isolating switch.

[0019] Preferably, the GIL input line and the GIL output line are both provided with pluggable cable heads.

[0020] Further preferably, there are three pluggable cable heads on the GIL input line and three pluggable cable heads on the GIL output line, corresponding to the three-phase interfaces of the first gas-insulated metal-enclosed switch and the second gas-insulated metal-enclosed switch respectively.

[0021] Compared with the prior art, the beneficial effects of the technical solution of the utility model are:

[0022] The utility model provides a fully insulated incoming line structure for a step-up substation, which has the following advantages:

[0023] 1) In this application, the insulating medium in the incoming line of the step-up substation adopts insulating gas such as sulfur hexafluoride, which has a small requirement for the insulation distance of the equipment and can reduce the equipment size and floor space.

[0024] 2) In this application, the entire incoming line structure of the step-up substation has no exposed live parts, is less affected by external factors, and is safer.

[0025] 3) Three-phase pluggable cable heads are set on the GIL input line and the GIL output line, corresponding to the circuit breakers, grounding switches and voltage transformers of the first gas-insulated metal-enclosed switch and the second gas-insulated metal-enclosed switch respectively. By opening the three-position disconnector, the first gas-insulated metal-enclosed switch and the second gas-insulated metal-enclosed switch, the experimental tooling can be connected to the pluggable cable heads at the corresponding positions to perform pressure tests on the first gas-insulated metal-enclosed switch and the second gas-insulated metal-enclosed switch to ensure line safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a front view structural diagram of the utility model;

[0028] Figure 2 It is a schematic diagram of the top structure of the utility model.

[0029] Explanation of the markings in the figure: 1. First switch distribution cabinet; 2. GIL input line; 3. Plug-in cable head; 4. First gas-insulated metal-enclosed switch; 5. Three-position disconnector; 6. Step-up transformer; 7. GIL output line; 8. Second gas-insulated metal-enclosed switch; 9. Second switch distribution cabinet. DETAILED DESCRIPTION

[0030] In order to better understand the purpose, structure and function of the present invention, the technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific preferred embodiments.

[0031] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper", "lower", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second", etc. do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in the embodiments are only for illustrating the technical solution and do not limit the scope of protection of the present invention. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0032] Unless otherwise expressly specified or limited, terms such as "installed," "installed," "connected," and "fixed" should be interpreted broadly. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0033] Example 1:

[0034] See also Figure 1-2 The present application provides a fully insulated incoming line structure for a step-up substation, including a low-voltage incoming line section consisting of a first switch distribution cabinet 1, a GIL input line 2, a first gas-insulated metal-enclosed switch 4, a GIL input line 2, and a step-up transformer 6. The 35kV low voltage is gathered through the first switch distribution cabinet 1 and connected to the step-up transformer 6 through the GIL input line 2 for step-up. The first gas-insulated metal-enclosed switch 4 is arranged in the middle of the GIL input line 2. The first gas-insulated metal-enclosed switch 4 includes a circuit breaker, a grounding switch and a voltage transformer. The circuit breaker is used for line disconnection; the grounding switch is used for equipment maintenance; and the voltage transformer is used for equipment monitoring.

[0035] After being boosted by the step-up transformer 6, the current flows from the other side of the step-up transformer 6 through the GIL output line 7, the second gas-insulated metal-enclosed switch 8, and the GIL output line 7 into the second switch distribution cabinet 9, and finally flows into the power grid and is transmitted to the power-consuming equipment. The second gas-insulated metal-enclosed switch 8 includes a circuit breaker, an earthing switch, and a voltage transformer. The circuit breaker is used for line disconnection; the earthing switch is used for equipment maintenance; and the voltage transformer is used for equipment monitoring. The boosted voltage is 110kV or 220kV, suitable for construction in underground substations or urban substations.

[0036] Compared with the traditional step-up substation, the above embodiment adopts GIL (gas insulated metal enclosed transmission line) for its incoming and outgoing line structures. The safety distance between the lines is smaller than that of the existing exposed incoming line substation, which can reduce the equipment size and floor space. At the same time, there are no exposed live parts, which is less affected by external factors and is safer.

[0037] Furthermore, the insulating gas in the GIL input line 2 and the GIL output line 7 is SF6.

[0038] Furthermore, the GIL input line 2 and the GIL output line 7 are both connected to the step-up transformer 6 through a three-position disconnector 5. The three-position disconnector 5 has a closing position, an opening position, and a grounding position, and the three-position disconnector 5 only has a single pole. The single pole represents different states in different positions, while the traditional disconnector is a double pole, including a main pole and a ground pole, which may cause misoperation. The three-position disconnector 5 uses a single pole in combination with a current electrical lock for control, which can avoid the possibility of misoperation.

[0039] Example 2:

[0040] Based on the above embodiment, Figure 1 As shown, both the GIL input line 2 and the GIL output line 7 are provided with pluggable cable heads 3 .

[0041] The difference from Example 1 is that a plug-in cable head 3 for experimental testing is designed in the fully insulated incoming line structure of the step-up substation, which is convenient for performing corresponding tests on the three-phase of the first gas-insulated metal-enclosed switch 4 or the three-phase of the second gas-insulated metal-enclosed switch 8, such as pressure testing, etc. At the same time, the plug-in cable head 3 is preferably a quick-plug connector, which is convenient for connection and saves replacement time.

[0042] Furthermore, Figure 1 As shown, there are three pluggable cable heads 3 on the GIL input line 2 and three pluggable cable heads 3 on the GIL output line 7, which correspond to the three-phase interfaces of the first gas-insulated metal-enclosed switch 4 and the second gas-insulated metal-enclosed switch 8 respectively.

[0043] The three pluggable cable heads 3 on the GIL input line 2 or the GIL output line 7 correspond to the circuit breaker, grounding switch and voltage transformer of the first gas-insulated metal-enclosed switch 4 or the second gas-insulated metal-enclosed switch 8, respectively. By disconnecting the three-position disconnector 5, the first gas-insulated metal-enclosed switch 4 and the second gas-insulated metal-enclosed switch 8, the GIS test tooling can be connected to the pluggable cable heads at the corresponding positions to perform pressure tests on the first gas-insulated metal-enclosed switch 4 and the second gas-insulated metal-enclosed switch 8 to ensure line safety.

[0044] The specific implementation methods of this application are as follows:

[0045] External power supplies or power generation equipment are collected through the 35kV low-voltage first switch distribution cabinet 1, and then the first switch distribution cabinet 1 is closed and connected to the first gas-insulated metal-enclosed switch 4 through the GIL input line 2. The first gas-insulated metal-enclosed switch 4 includes a circuit breaker, an earthing switch and a voltage transformer. The circuit breaker is used for line disconnection, the earthing switch is used for equipment maintenance, and the voltage transformer is used for equipment monitoring. The first gas-insulated metal-enclosed switch 4 is then connected to the step-up transformer 6 via the GIL transmission line 2. A three-position disconnector 5 is provided at the connection between the GIL transmission line 2 and the step-up transformer 6. After the step-up transformer 6 boosts the voltage, it passes through another three-position disconnector 5 and enters the GIL output line 7. The GIL output line 7 is then connected to the second gas-insulated metal-enclosed switch 8. The second gas-insulated metal-enclosed switch 8 also includes a circuit breaker, an earthing switch, and a voltage transformer. The circuit breaker is used for line disconnection, the earthing switch is used for equipment maintenance, and the voltage transformer is used for equipment monitoring. The second gas-insulated metal-enclosed switch 8 is then connected to the second switch distribution cabinet 9 via the GIL output line 7, ultimately transmitting the high voltage electricity to the power grid. A three-phase pluggable cable head 3 is provided on the GIL input line 2 and the GIL output line 7. During the on-site incoming line equipment test, pressure can be applied through the pluggable cable head 3, and the three-position disconnector 5 and the first gas-insulated metal-enclosed switch 4 circuit breaker in the low-voltage section are disconnected, or the three-position disconnector 5 and the second gas-insulated metal-enclosed switch 8 circuit breaker in the high-voltage section are disconnected to meet the relevant test requirements of the transformer and the first gas-insulated metal-enclosed switch 4 and the second gas-insulated metal-enclosed switch 8.

[0046] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. A person skilled in the art will be able to make other variations or modifications based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A fully insulated incoming line structure for a step-up substation, characterized by: include, A low-voltage section, wherein the current in the low-voltage section flows through the power generation equipment into the first switch distribution cabinet (1), the GIL input line (2), the first gas-insulated metal-enclosed switch (4), the GIL input line (2), and finally into the step-up transformer (6); A high-voltage section, wherein the current in the high-voltage section is boosted by a boost transformer (6), passes through a GIL output line (7), a second gas-insulated metal-enclosed switch (8), and the GIL output line (7) in sequence, enters a second switch distribution cabinet (9), and finally flows into the power grid.

2. The fully insulated incoming line structure of a step-up substation according to claim 1, characterized in that: The voltage in the low-voltage section is 35 kV; the voltage in the high-voltage section is 110 kV or 220 kV.

3. The fully insulated incoming line structure of a step-up substation according to claim 1, characterized in that: The insulating gas in the GIL input line (2) and the GIL output line (7) is SF6.

4. The fully insulated incoming line structure of a step-up substation according to claim 1, characterized in that: The first gas-insulated metal-enclosed switch (4) and the second gas-insulated metal-enclosed switch (8) both include a circuit breaker, a grounding switch and a voltage transformer, wherein: Circuit breakers are used to disconnect circuits; The grounding switch is used for equipment maintenance; Voltage transformers are used for equipment monitoring.

5. The fully insulated incoming line structure of a step-up substation according to claim 1, characterized in that: The GIL input line (2) and the GIL output line (7) are both connected to the step-up transformer (6) via a three-position isolating switch (5).

6. The fully insulated incoming line structure of a step-up substation according to any one of claims 1 to 5, characterized in that: The GIL input line (2) and the GIL output line (7) are both provided with plug-in cable heads (3).

7. The fully insulated incoming line structure of a step-up substation according to claim 6, characterized in that: There are three pluggable cable heads (3) on the GIL input line (2) and three pluggable cable heads (3) on the GIL output line (7), respectively corresponding to the three-phase interfaces of the first gas-insulated metal-enclosed switch (4) and the second gas-insulated metal-enclosed switch (8).

Images