阅读说明：本技术 一种分体式有载分接开关及其控制方法 (Split type on-load tap-changer and control method thereof ) 是由 吕玮 曹冬明 方太勋 陈羽 孙超 杨兵 许元震 刘少飞 王文杰 于 2021-06-24 设计创作，主要内容包括：本申请提供一种分体式有载分接开关及其控制方法。所述分体式有载分接开关包括分接选择器同步单元和分接开关控制单元,所述分接选择器同步单元设置于变压器外部,通过第一传动单元与变压器的分接选择器同步动作,所述分接选择器在调节所述变压器电压时动作,所述分接选择器同步单元检测到所述分接选择器动作到位后,发出分接选择器动作到位信号；所述分接开关控制单元设置于变压器外部,接收到来自于所述分接选择器同步单元的所述分接选择器动作到位信号,控制变压器的切换开关进行电流切换。(The application provides a split type on-load tap-changer and a control method thereof. The split type on-load tap-changer comprises a tap selector synchronizing unit and a tap-changer control unit, wherein the tap selector synchronizing unit is arranged outside the transformer and synchronously acts with a tap selector of the transformer through a first transmission unit, the tap selector acts when the voltage of the transformer is adjusted, and the tap selector synchronizing unit sends a tap selector action in-place signal after detecting that the tap selector acts in place; the tapping switch control unit is arranged outside the transformer, receives the tapping selector action in-place signal from the tapping selector synchronization unit and controls a selector switch of the transformer to switch current.)

1. A split on-load tap changer comprising:

the tapping selector synchronizing unit is arranged outside the transformer and synchronously acts with a tapping selector of the transformer through the first transmission unit, the tapping selector acts when the voltage of the transformer is adjusted, and the tapping selector synchronizing unit sends a tapping selector action in-place signal after detecting that the tapping selector acts in place;

and the tapping switch control unit is arranged outside the transformer, receives the tapping selector action in-place signal from the tapping selector synchronization unit and controls a selector switch of the transformer to switch current.

2. The split on-load tap changer of claim 1, further comprising:

the tapping selector is arranged in the transformer and is connected with a voltage regulating winding of the transformer;

the tapping selector driving motor is arranged outside the transformer, is connected with the tapping selector through the first transmission unit and the second transmission unit and drives the tapping selector to act;

the change-over switch is arranged outside the transformer and is respectively connected with the tapping selector and the tapping switch control unit;

and the isolation module comprises a conductor and an insulating shell, the conductor is connected with the tapping selector and the change-over switch, and the insulating shell isolates the conductor from the transformer shell.

3. The split on-load tap changer of claim 1 or 2, wherein the first transmission unit comprises:

and the first gear box is connected with the synchronous unit of the tapping selector through a first transmission shaft and connected with the tapping selector through a second transmission shaft.

4. The split on-load tap changer of claim 2, wherein the second transmission unit comprises:

and the second gear box is connected with the tapping selector driving motor through a third transmission shaft and is connected with the first gear box through a fourth transmission shaft.

5. The split on-load tap changer of claim 2, wherein the tap changer control unit is further connected to the tap selector drive motor, and upon receiving a command to adjust the transformer voltage, controls the tap selector drive motor to actuate the tap selector.

6. The split on-load tap changer of claim 1, wherein the voltage regulation winding of the transformer comprises N taps, each tap corresponding to 1 step, and N is a natural number.

7. The split on-load tap changer of claim 2, wherein the isolation module comprises a first isolation unit and a second isolation unit connected to the tap selector and the diverter switch, one side of the first isolation unit and the second isolation unit being disposed inside the transformer and the other side being disposed outside the transformer, the first isolation unit comprising the first conductor and the first housing, the second isolation unit comprising the second conductor and the second housing.

8. The split on-load tap changer of claim 7, wherein the tap selector comprises:

the movable first contact is connected with the selector switch through the first isolation unit;

the movable second contact is connected with the selector switch through the second isolation unit;

and the N fixed contacts are respectively connected with N taps of the voltage regulating winding of the transformer in a one-to-one correspondence mode, and N is a natural number.

9. The split on-load tap changer of claim 7, wherein the diverter switch comprises:

the first input end is connected with the tapping selector through the first isolation unit;

and the second input end is connected with the tapping selector through the second isolation unit.

10. The split on-load tap changer of claim 1, wherein the diverter switch comprises an oil switch, a vacuum switch, or a power electronic type switch, and the external insulation is gas or liquid insulation.

11. The split on-load tap changer of claim 1, wherein the tap selector action bit signal comprises a node signal or an optical signal.

12. A method of controlling a split on-load tap changer, comprising:

after receiving a command for adjusting the voltage of the transformer, the tapping switch control unit controls a tapping selector to drive a motor to drive the tapping selector to act;

and receiving a tapping selector action in-place signal from the tapping selector synchronization unit, and controlling a change-over switch of the transformer to switch the current.

Technical Field

The application relates to the technical field of transformers, in particular to a split type on-load tap-changer and a control method thereof.

Background

The on-load tap-changer mainly has the main function of realizing transformer voltage regulation, and compared with the operation condition of a common power transformer, the converter transformer on-load tap-changer (hereinafter referred to as OLTC) in an extra-high voltage direct current transmission project is worse: 1. the load running at the end of the longer commutation period is large, and the current flowing through the OLTC is large; 2. the load current flowing through the on-load tap-changer is not a sine wave but a current waveform with a phase change process, the di/dt of a zero crossing point is large, and arc quenching is difficult. 3. The converter transformer OLTC has very frequent actions, the action frequency in operation can reach 4000 times/year, and the requirement on the mechanical life is high; 4. the internal action is not monitored by any electrical quantity, is in a 'black box' state, and cannot judge the transient working state in the switching process. Due to the particularity of the extra-high voltage converter transformer OLTC, the OLTC in all extra-high voltage direct current transmission projects in China is provided by foreign manufacturers at present, and accident analysis and improvement cannot be controlled independently.

The OLTC used at present, no matter in a non-vacuum type or a vacuum type, needs to adopt insulating oil as a medium for breaking or heat dissipation, and because the OLTC is installed inside a transformer, when the OLTC breaks down, the OLTC is easy to cause fire and explosion, so that the whole transformer is burnt completely, and the consequences are serious.

To the above problem, prior art has proposed a novel OLTC, has increased 2 isolating device, keeps apart shunting selector and change over switch, has solved the influence problem of change over switch self trouble to the transformer body. However, the problem of controlling the sequence of the actions between the tapping selector and the change-over switch is not considered, and the situation that the tapping selector is not pre-selected in place and the change-over switch starts to act easily occurs, and the change-over switch explodes at the moment.

Disclosure of Invention

The embodiment of the application provides a split type on-load tap-changer, which comprises a tap selector synchronizing unit and a tap-changer control unit, wherein the tap selector synchronizing unit is arranged outside a transformer and synchronously acts with a tap selector of the transformer through a first transmission unit, the tap selector acts when the voltage of the transformer is adjusted, and the tap selector synchronizing unit sends a tap selector action in-place signal after detecting that the tap selector acts in place; the tapping switch control unit is arranged outside the transformer, receives the tapping selector action in-place signal from the tapping selector synchronization unit and controls a selector switch of the transformer to switch current.

According to some embodiments, the split on-load tap-changer further comprises a tap selector, a tap selector driving motor, a diverter switch and an isolation module, wherein the tap selector is arranged inside the transformer and connected with a voltage regulating winding of the transformer; the tapping selector driving motor is arranged outside the transformer and is connected with the tapping selector through a first transmission unit and a second transmission unit to drive the tapping selector to act; the change-over switch is arranged outside the transformer and is respectively connected with the tapping selector and the tapping switch control unit; the isolation module comprises a conductor and an insulating shell, the conductor is connected with the tapping selector and the selector switch, and the insulating shell isolates the conductor from the transformer shell.

According to some embodiments, the first transmission unit comprises a first gear box connected to the tap selector synchronisation unit via a first transmission shaft and connected to the tap selector via a second transmission shaft.

According to some embodiments, the second transmission unit comprises a second gear box connected to the tap selector drive motor via a third transmission shaft and to the first gear box via a fourth transmission shaft.

According to some embodiments, the tap changer control unit is further connected with the tap selector driving motor, and after receiving a command for adjusting the voltage of the transformer, the tap selector driving motor is controlled to drive the tap selector to act.

According to some embodiments, the voltage regulating winding of the transformer comprises N taps, each tap corresponds to 1 gear, and N is a natural number.

According to some embodiments, the isolation module comprises a first isolation unit and a second isolation unit connected with the tap selector and the diverter switch, one side of the first isolation unit and the second isolation unit is arranged inside the transformer, the other side of the first isolation unit and the second isolation unit is arranged outside the transformer, the first isolation unit comprises a first conductor and a first shell, and the second isolation unit comprises a second conductor and a second shell.

According to some embodiments, the tap selector comprises a movable first contact, a movable second contact and N fixed contacts, the movable first contact being connected with the diverter switch through the first isolation unit; the movable second contact is connected with the change-over switch through the second isolation unit; and the N fixed contacts are respectively connected with N taps of the voltage regulating winding of the transformer in a one-to-one correspondence manner.

According to some embodiments, the diverter switch comprises a first input and a second input, the first input being connected to the tap selector through the first isolation unit; the second input end is connected with the tapping selector through the second isolation unit.

According to some embodiments, the diverter switch comprises an oil switch, a vacuum switch or a power electronic type switch, the external insulation being gas or liquid insulation.

According to some embodiments, the tap selector action to bit signal comprises a node signal or an optical signal.

The embodiment of the application further provides a control method of the split on-load tap-changer, which includes: after receiving a command for adjusting the voltage of the transformer, the tapping switch control unit controls a tapping selector to drive a motor to drive the tapping selector to act; and receiving a tapping selector action in-place signal from the tapping selector synchronization unit, and controlling a change-over switch of the transformer to switch the current.

According to the technical scheme, the isolating device is arranged between the selector switch and the tap selector, the tap selector synchronizing unit and the tap switch control unit are adopted, the selector switch which is easy to break down and bears the switching process is separated from the transformer, serious faults caused by the action time sequence errors of the tap selector and the selector switch are avoided, the influence of the faults of the existing on-load tap switch on the transformer body is solved, and the engineering reliability is guaranteed.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic view of a split on-load tap changer according to an embodiment of the present disclosure.

Fig. 2 is a schematic flowchart of a control method of a split on-load tap changer according to an embodiment of the present application.

Fig. 3 is an operation schematic diagram of a split on-load tap changer according to an embodiment of the present application.

Fig. 4 is an operation schematic diagram of another split type on-load tap changer provided by the embodiment of the application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be understood that the terms "first", "second", etc. in the claims, description, and drawings of the present application are used for distinguishing between different objects and not for describing a particular order. The terms "comprises" and "comprising," when used in the specification and claims of this application, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Fig. 1 is a schematic diagram of a split on-load tap changer according to an embodiment of the present disclosure, which includes a tap selector 300, a tap selector driving motor 301, a diverter switch 500, an isolation module 400, a tap selector synchronization unit 700, and a tap changer control unit 600.

The tap selector 300 is disposed inside the transformer 100 and connected to the voltage regulating winding 200 of the transformer 100. The tap selector driving motor 301 is disposed outside the transformer 100, and is connected to the tap selector 300 through the first transmission unit and the second transmission unit to drive the tap selector 300. Diverter switch 500 is disposed outside transformer 100 and is connected to tap selector 300 and tap switch control unit 600, respectively. The isolation module 400 includes conductors that interface with the tap selector 300 and the diverter switch 500 and an insulating housing that isolates the conductors from the transformer 100 housing. The tap selector synchronization unit 700 is disposed outside the transformer 100, and synchronously operates with the tap selector 300 through the first transmission unit, the tap selector 300 operates when the voltage of the transformer 100 is adjusted, and the tap selector synchronization unit 700 sends out a signal that the tap selector 300 operates in place after detecting that the tap selector 300 operates in place. The tap changer control unit 600 is disposed outside the transformer 100, and receives the operation-in-place signal of the tap selector 300 from the tap selector synchronization unit 700 to control the diverter switch 500 of the transformer 100 to switch the current. Tap selector 300 acts on bit signals including, but not limited to, node signals or optical signals.

The first transmission unit comprises a first gear box 306 connected to the tap selector synchronisation unit 700 via a first transmission shaft 305 and to the tap selector 300 via a second transmission shaft 307. The first transmission shaft 305 is disposed outside the transformer 100, the second transmission shaft 307 is disposed inside the transformer 100, and the tap selector synchronization unit 700 and the tap selector 300 operate synchronously under the driving of the first gear box 306.

The second transmission unit comprises a second gear box 303 connected to a tap selector drive motor 301 via a third transmission shaft 302 and to a first gear box 306 via a fourth transmission shaft 304. The third transmission shaft 302 is disposed outside the transformer 100, and the fourth transmission shaft 304 is disposed outside the transformer 100. The tap selector driving motor 301 drives the tap selector 300 to act through the first transmission unit and the second transmission unit.

The tap changer control unit 600 is further connected to the tap selector driving motor 301, and controls the tap selector driving motor 301 to drive the tap selector 300 to operate after receiving a command for adjusting the voltage of the transformer 100.

The voltage regulating winding 200 of the transformer 100 includes N taps, each tap corresponds to 1 step, and N is a natural number.

The isolation module 400 includes a first isolation unit 401 and a second isolation unit 402, which are connected to the tap selector 300 and the switch 500, and one side of the first isolation unit 401 and the second isolation unit 402 is disposed inside the transformer, and the other side is disposed outside the transformer. The first isolation unit comprises a first conductor and a first shell, the second isolation unit comprises a second conductor and a second shell, and the first conductor and the second conductor are electrically isolated from the shell of the transformer 100 respectively by the first shell and the second shell and have the functions of sealing the transformer oil chamber and sealing the transformer oil chamber.

One end of each of the two isolation units is connected with the tap selector 300, and the other end of each of the two isolation units is connected with the selector switch 500, so that the current in the transformer regulating winding 200 is led out from the tap selector 300 to the selector switch 500 through the first isolation unit 401 or the second isolation unit 402.

The tap selector 300 comprises a movable first contact, a movable second contact and N fixed contacts, wherein the movable first contact is connected with the diverter switch 500 through a first isolation unit 401, and the movable second contact is connected with the diverter switch 500 through a second isolation unit 402; the N fixed contacts are connected to N taps of the voltage regulating winding 200 of the transformer 100, respectively, in a one-to-one correspondence, where N is a natural number.

Diverter switch 500 includes a first input connected to tap selector 300 through first isolation unit 401 and a second input connected to tap selector 300 through second isolation unit 402.

The switch 500 includes an oil switch, a vacuum switch or a power electronic switch, and the external insulation is gas or liquid insulation, but not limited thereto.

Fig. 2 is a schematic flowchart of a control method of a split on-load tap changer according to an embodiment of the present application.

In S10, tap changer control unit 600 controls tap selector driving motor 301 to drive tap selector 300 in response to the command for adjusting the voltage of transformer 100.

This embodiment is explained based on two kinds of operation schematic diagrams of the split type on-load tap-changer of the embodiments of fig. 3 and 4.

As shown in fig. 3, the movable second contact of the tap selector 300 is in the 8 th gear of the transformer regulating winding, the movable first contact is in the 7 th gear of the transformer regulating winding 200, and the current flows through the 8 th gear of the transformer regulating winding 200, the movable second contact of the tap selector 300, the second isolating unit 402 and the change-over switch 500.

At this time, after receiving the voltage up-shift operation command of the external regulating transformer 100, the tap switch control unit 600 sends an operation command to the tap selector driving motor 301, the tap selector driving motor 301 rotates to drive the tap selector 300 to operate through the third transmission shaft 302, the second gear box 303, the fourth transmission shaft 304, the first gear box 306, and the second transmission shaft 307, respectively, so as to operate the movable first contact to the 9 th gear of the transformer regulating winding 200 shown in fig. 4 in the non-excitation state, and prepare for subsequent current switching.

In S20, tap changer control section 600 receives the tap selector 300 operation-in-place signal from tap selector synchronization section 700, and controls changeover switch 500 of transformer 100 to perform current switching.

The tap selector synchronizing unit 700 obtains a signal that the movable first contact of the tap selector 300 is in place through the third transmission shaft 302, the second gear box 303, the fourth transmission shaft 304, the first gear box 306, and the first transmission shaft 305, and sends an electrical node or optical signal to the tap switch control unit 600. After receiving the signal indicating that the movable first contact of the tap selector 300 is in place, the tap switch control unit 600 sends an action command to the switch 500, and the switch 500 performs a current switching operation to switch the current from the movable second contact of the tap selector 300 to the movable first contact. At this time, as shown in fig. 4, the current of the transformer 100 flows through the 9 th stage of the transformer regulating winding 200, the movable first contact of the tap selector 300, the first isolating unit 401 and the switch 500, respectively, and the up-shift operation is completed.

The downshift operation is consistent with the above process, and the action direction is opposite, which is not described in detail.

According to the technical scheme, the isolating device is arranged between the selector switch and the tap selector, the tap selector synchronizing unit and the tap switch control unit are adopted, the selector switch which is easy to break down and bears the switching process is separated from the transformer, serious faults caused by the action time sequence errors of the tap selector and the selector switch are avoided, the influence of the faults of the existing on-load tap switch on the transformer body is solved, and the engineering reliability is guaranteed.

The above embodiments are only for illustrating the technical idea of the present application, and the protection scope of the present application is not limited thereby, and any modifications made on the basis of the technical solution according to the technical idea presented in the present application fall within the protection scope of the present application.