750kV main transformer neutral point reactor
By designing the combination of the first double column and the second double column horizontal rotary isolating switch on the neutral point side of the 750kV main transformer, independent grounding of the reactor and the lightning arrester is solved, and the problem of the lightning arrester and the reactor in parallel in the operating circuit cannot be repaired in the existing design, ensuring the safe and stable operation of the power grid.
Patent Information
- Application Number
- CN202421324766.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-12
- Publication Date
- 2025-04-04
- Estimated Expiration
- 2034-06-12
AI Technical Summary
The neutral point side design of existing substation main transformers usually uses direct grounding or neutral point small reagent grounding, which causes the lightning arrester and reactor to be connected in parallel on the operating circuit and cannot be inspected.
A 750kV main transformer neutral point reactor is designed, and a combination of the first double-column horizontal rotary isolator and the second double-column horizontal rotary isolator is used. By setting a grounding end and a double-column rotary isolator without grounding, independent grounding of the reactor and the lightning arrester are achieved, so that maintenance is carried out without affecting the operation of the power grid.
It realizes a flexible operation mode on the neutral point side of the main transformer of the substation, which can be converted to a direct grounding method when a fault occurs, avoids the overall power outage of the main transformer, ensures the safe and stable operation of the power grid, and solves the problem of lightning arresters and reactors not being inspected.
Smart Images
Figure CN222720203U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of power transmission and transformation, and specifically discloses a neutral point reactor of a 750kV main transformer. Background Art
[0002] The neutral point side of the main transformer of a 750kV substation is usually designed with direct grounding or neutral point small reactance grounding. The existing design methods are as follows: Figure 1 As shown, in order to connect the lightning arrester to the N phase of the main bus, the operating mode is to open the double-column V-type rotary grounding switch, and the neutral point of the main transformer is grounded through the reactor. When the grounding switch is closed, the neutral point of the main transformer is directly grounded. When the reactor or lightning arrester fails, the grounding switch can choose direct grounding for protection, but the lightning arrester and the reactor are still connected in parallel in the operating circuit and cannot be repaired.
[0003] Therefore, in view of this, the inventor provides a 750kV main transformer neutral point reactor to solve the above problems. Utility Model Content
[0004] The utility model aims to solve the problem that the neutral point side of the existing substation main transformer is usually designed according to direct grounding or neutral point small reactance grounding, resulting in the lightning arrester and the reactor still being connected in parallel in the operating circuit and unable to be repaired.
[0005] In order to achieve the above-mentioned purpose, the basic scheme of the utility model provides a 750kV main transformer neutral point reactor, including a main bus and a 750kV line connected to the main bus, characterized in that it also includes a first double-column horizontal rotating disconnector whose input end is connected to the main bus, and a second double-column horizontal rotating disconnector connected to the output end of the first double-column horizontal rotating disconnector, the output end of the second double-column horizontal rotating disconnector is connected to a zinc oxide lightning arrester, the output end of the zinc oxide lightning arrester is connected to a neutral point reactor, the neutral point reactor is grounded, and the first double-column horizontal rotating disconnector is provided with a grounding terminal.
[0006] The principles and effects of this basic solution are:
[0007] 1. Compared with the prior art, the utility model analyzes the shortcomings of the traditional grounding method of the neutral point reactor of the transformer, and sets a group of first double-column horizontal rotating disconnectors, sets a grounding terminal for them, and cooperates with a group of non-grounded second double-column horizontal rotating disconnectors. When the first double-column horizontal rotating disconnector is grounded, the neutral point of the main transformer is directly grounded, and the overall circuit is completely disconnected from the neutral point of the main transformer. At the same time, the reactor and the lightning arrester are grounded through the second double-column horizontal rotating disconnector, thereby protecting the reactor. This solves the problem that the neutral point side of the main transformer of the existing substation is usually designed according to direct grounding or neutral point small reactor grounding, resulting in the lightning arrester and the reactor still being connected in parallel in the operating circuit and unable to be repaired.
[0008] Furthermore, the main bus has a voltage level of 750 kV or above.
[0009] Furthermore, the neutral point reactor is a controllable reactor.
[0010] Furthermore, the first double-column horizontal rotary isolating switch and the second double-column horizontal rotary isolating switch both include a base, a straight column insulator, a lead-out seat and a contact.
[0011] Furthermore, the zinc oxide lightning arrester is a high voltage zinc oxide lightning arrester.
[0012] Furthermore, a release seat is provided at the bottom of the zinc oxide arrester. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.
[0014] Figure 1 The present invention shows a schematic diagram of the existing connection of the neutral point reactor of the 750kV main transformer proposed in the embodiment of the present application;
[0015] Figure 2 A schematic diagram of a 750kV main transformer neutral point reactor proposed in an embodiment of the present application is shown;
[0016] Figure 3 The figure shows a connection diagram of a neutral point reactor of a 750kV main transformer proposed in an embodiment of the present application;
[0017] Figure 4 A schematic diagram of a grounding rod of a 750kV main transformer neutral point reactor proposed in an embodiment of the present application is shown;
[0018] Figure 5A connection diagram of a second double-column horizontal rotary switch of a 750 kV main transformer neutral point reactor proposed in an embodiment of the present application is shown. DETAILED DESCRIPTION
[0019] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the utility model, the specific implementation method, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.
[0020] The reference numerals in the drawings of the specification include: a first double-pole horizontal rotary disconnector 1 , a second double-pole horizontal rotary disconnector 2 , a zinc oxide lightning arrester 3 , a neutral point reactor 4 , a straight column insulator 5 , and a direct grounding rod 6 .
[0021] 750kV main transformer neutral point reactor, implementation example Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown: it includes a main bus and a 750kV line connected to the main bus. The main bus has a voltage level of 750kV and above. In this embodiment, the main bus has a voltage level of 750kV, thereby ensuring that various power equipment and the power system itself can still operate normally.
[0022] With traditional Figure 1 Compared with the wiring method, the utility model also includes a first double-pole horizontal rotating isolating switch 1 whose input end is connected to the main bus, the on-off end of the first double-pole horizontal rotating isolating switch 1 is DS1, and the first double-pole horizontal rotating isolating switch 1 is provided with a grounding end, the grounding end is ES1, and the grounding end is a direct grounding rod 6 connected to the first double-pole horizontal rotating isolating switch 1.
[0023] The output end of the first double-pole horizontal rotary isolating switch 1 is connected to the second double-pole horizontal rotary isolating switch 2, the on-off end of the second double-pole horizontal rotary isolating switch 2 is DS2, the output end of the second double-pole horizontal rotary isolating switch 2 is connected to the zinc oxide lightning arrester 3, the output end of the zinc oxide lightning arrester 3 is connected to the neutral point reactor 4, the neutral point reactor 4 is grounded, the first double-pole horizontal rotary isolating switch 1 is provided with a grounding terminal, the zinc oxide lightning arrester is also connected to a straight column insulator 5, the straight column insulator 5 can play an important role in the overhead transmission line, can support the conductor and prevent the current from returning to the ground, and is widely used in the main bus.
[0024] The main busbar has a voltage level of 750kV and above, and the neutral point reactor 4 is a controllable reactor. The controllable reactor has the advantages of voltage regulation, power factor correction, on-demand adjustment of reactive power, and suspension regulation. The first double-pole horizontal rotary disconnector 1 and the second double-pole horizontal rotary disconnector 2 both include a base, a straight column insulator 5, an outlet seat and a contact. The zinc oxide lightning arrester 3 is a high-voltage zinc oxide lightning arrester 3, which is suitable for high-voltage use of 750kV. A disconnect seat is provided at the bottom of the zinc oxide lightning arrester 3, and the zinc oxide lightning arrester 3 is protected by the set disconnect seat. When the zinc oxide lightning arrester 3 deteriorates or fails due to damage, the disconnect seat will act quickly to withdraw the single faulty lightning arrester from the transmission system to ensure the continuous operation of the power system.
[0025] The use process of the utility model is as follows:
[0026] When DS1 is opened and ES1 is closed, the neutral point of the main transformer is directly grounded, the overall reactor circuit is completely disconnected from the neutral point of the main transformer, and the reactor and lightning arrester can be directly grounded through DS2.
[0027] Compared with the traditional main transformer neutral point grounding scheme, this scheme is convenient for dispatching and flexible adjustment of the operation mode, and when the neutral point reactor 4 or the arrester outgoing line fails, it can be converted to ES1 direct grounding mode, which is convenient for maintenance at any time and avoids the risk of overall power outage of the main transformer. It is conducive to the safe and stable operation of the power grid.
[0028] When DS1 is closed, ES1 is open, and DS2 is open, the reactor and lightning arrester are connected to the neutral point of the main transformer. The operation mode is flexible and changeable.
[0029] The utility model solves the problem that the neutral point side of the existing substation main transformer is usually designed according to direct grounding or neutral point small reactance grounding, resulting in the arrester and the reactor still being connected in parallel in the operating circuit and unable to be repaired.
[0030] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.
Claims
1. 750kV main transformer neutral point reactor, including main bus and 750kV line connected to the main bus, characterized in that: It also includes a first double-column horizontal rotary isolating switch with an input end connected to the main bus, and a second double-column horizontal rotary isolating switch connected to the output end of the first double-column horizontal rotary isolating switch, the output end of the second double-column horizontal rotary isolating switch is connected to a zinc oxide lightning arrester, the output end of the zinc oxide lightning arrester is connected to a neutral point reactor, the neutral point reactor is grounded, and the first double-column horizontal rotary isolating switch is provided with a grounding terminal.
2. The 750kV main transformer neutral point reactor according to claim 1, characterized in that: The main busbar has a voltage level of 750kV and above.
3. The 750kV main transformer neutral point reactor according to claim 1, characterized in that: The neutral point reactor is a controllable reactor.
4. The 750kV main transformer neutral point reactor according to claim 1, characterized in that: The first double-column horizontal rotary isolating switch and the second double-column horizontal rotary isolating switch both include a base, a straight column insulator, a lead-out seat and a contact.
5. The 750kV main transformer neutral point reactor according to claim 1, characterized in that: The zinc oxide lightning arrester is a high voltage zinc oxide lightning arrester.
6. The 750kV main transformer neutral point reactor according to claim 5, characterized in that: A separation seat is provided at the bottom of the zinc oxide arrester.