CN112071672B - Vacuum on-load tap-changer transition device and switching method of transition device - Google Patents

Abstract

The invention discloses a transition device of a vacuum on-load tap-changer, comprising: a main transfer switch S1, an auxiliary transfer switch S2, circulation vacuum circuit breakers RV1 and RV2, a load current vacuum circuit breaker MV and transition resistors R1 and R2; compared with the existing structure transition circuit, the device can obviously reduce the action parts in the tap changer, reduce the complexity of the mechanical structure, balance the switching capacity of the circulating current vacuum circuit breaker and the load current vacuum circuit breaker, improve the electrical service life of the whole vacuum on-load tap changer, and solve the problems of the existing device that the mechanical structure is complicated and the electrical service life of the vacuum on-load tap changer is low.

Description

A vacuum on-load tap-changer transition device and a switching method for the transition device

technical field

The application relates to the field of tap changer transition, in particular to a vacuum on-load tap-changer transition device, and also to a switching method of the vacuum on-load tap-changer transition device.

Background technique

The on-load tap-changer is a switching device that provides a constant voltage to the transformer when the load changes. The basic principle is to realize the switching between the taps in the transformer winding under the condition of ensuring that the load current is not interrupted, so as to change the number of turns of the winding, that is, the voltage ratio of the transformer, and finally achieve the purpose of voltage regulation. The vacuum type on-load tap-changer mainly relies on the vacuum tube of the switch to achieve arc extinguishing, and the arc and hot gas are not exposed; the oil in the oil chamber of the tap-changer will not be carbonized and polluted, and the oil does not need to be purified; the burning of the contacts in the vacuum tube Corrosion damage can be minimized. The on-load tap-changer is mainly composed of a change-over switch, a change-over selector and an electric mechanism.

The on-load tap-changer has a load switching, which requires a transition circuit and a selection circuit. Different voltage regulation methods require different voltage regulation circuits. Therefore, the circuit of the on-load tap-changer consists of a transition circuit, a selection circuit and a voltage regulation circuit. part composition. The transition circuit is a series resistance circuit connected across the tap points, and its corresponding mechanism is a switch or a selector switch, which is a tap for transforming the transformer windings in a charged state. The tap changer adopts the principle of transition circuit to realize the tap change operation. According to the number of transition circuit resistances, there are single resistance, double resistance, four resistance or multi-resistance transition, according to the contact fracture, there are single fracture, double fracture, etc., which can be combined to form various transition circuits. The transition circuit and switching procedure have different effects on the contact task of the diverter switch. Whether the arc can limit the reliable extinguishing of the first half cycle depends to a large extent on the required switching task.

In the past, the number of mechanical transfer switches in the switching core of the on-load tap-changer is relatively large. For one pole, it generally includes 2 main circuit switches and 2 auxiliary transfer switches, and the mechanical structure is relatively complex. And the vacuum circuit breaker without the transition resistance in the on-load tap-changer is the load vacuum circuit breaker, which only bears the task of breaking the load current; the vacuum circuit breaker connected with the transition resistance is the circulating current vacuum circuit breaker, which only bears breaking The task of internal circulation. According to the experience of UHV DC engineering, the single-column winding of commutation variable load current is generally 500-600A, and the internal circulating current flowing through the transition resistance is about 900-1000A. Since the internal circulating current passing through the circulating current vacuum circuit breaker is obviously larger than the load current, so After multiple switching, the degree of ablation of the load vacuum circuit breaker and the circulating vacuum circuit breaker is different, and the switching burden and electrical damage of the circulating vacuum circuit breaker will be more serious. Therefore, it is necessary to provide a transition circuit with a simple mechanical structure, which can reduce the switching task of the circulating vacuum bubble, balance the switching capacity of the load vacuum circuit breaker and the circulating vacuum circuit breaker, and thereby improve the electrical life of the entire vacuum on-load tap-changer.

SUMMARY OF THE INVENTION

The present application provides a transition device for a vacuum on-load tap-changer, which is used to solve the problems of complex mechanical structure of the existing device and low electrical life of the vacuum on-load tap-changer.

The present application provides a vacuum on-load tap changer transition device, comprising: a main transfer switch S1, an auxiliary transfer switch S2, circulating current vacuum circuit breakers RV1, RV2, load current vacuum circuit breakers MV, and transition resistors R1, R2;

The main transfer switch S1 has a total of four static contacts a, b, c and d; electrodes a and c are respectively connected to the on-load tap-changer tap selector odd-numbered gear and even-numbered gears, and electrodes b and d are respectively connected to the circulating current vacuum circuit breaker RV1, RV2, vacuum circuit breakers RV1, RV2 are respectively connected with transition resistances R1, R2, transition resistances R1, R2 are respectively connected with the odd-numbered and even-numbered gears of the on-load switch tap selector, and the fixed end of the action arm of the S1 transfer switch is connected to the transformer The moving contact can be rotated to connect the four static contacts a, b, c, and d;

Auxiliary transfer switch S2 has two static contacts, e and f; electrodes e and f are respectively connected to the on-load tap-changer tap selector for odd-numbered gears and even-numbered gears, and the fixed end of the S2 switch action arm passes through the load current vacuum circuit breaker MV Connect the neutral point of the transformer, and the moving contact can be rotated to select the two static contacts e and f;

The circulating vacuum circuit breaker RV1 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from the odd gear to the even gear;

The circulating current vacuum circuit breaker RV2 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from an even gear to an odd gear;

The load current vacuum circuit breaker MV is used to cut off the load current when the tap changer transition device is switched from odd to even and/or even to odd.

Preferably, the fixed end of the moving contact of the main transfer switch S1 and one end of the load current vacuum circuit breaker MV are both connected to the neutral point of the transformer to output current.

Preferably, it also includes:

When the gear position of the on-load tap-changer is in an odd-numbered tap, the moving contact of the action arm of the main transfer switch S1 conducts with the static contact a, and the moving contact of the action arm of the auxiliary transfer switch S2 conducts with the static contact e. Pass;

The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact a of the main transfer switch S1 through the S1 switch action arm, and the auxiliary transfer switch S2 is connected in parallel at the same time. e contact, load current circuit breaker MV output.

The application also provides a conversion method for a vacuum on-load tap-changer transition device, including:

Turn the moving contact of the action arm of the main transfer switch S1 from a to the static contact of b;

Disconnect the load current vacuum circuit breaker MV, cut off the load current, and generate arc;

When the arc in the load current vacuum circuit breaker MV is extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection e static contact to the connection f static contact;

Close the load current vacuum circuit breaker MV, and transfer the load current from the odd-numbered gear to the even-numbered gear, and the transition device connects the odd-numbered gear and the even-numbered gear at the same time to form a bridge and generate a circulating current;

Disconnect the circulating vacuum circuit breaker RV1, cut off the circulating current, and generate an arc;

When the arc in the circulating current vacuum circuit breaker RV1 is extinguished, the moving contact of the action arm of the main transfer switch S1 is changed from b to the c static contact, and at the same time, the circulating current vacuum circuit breaker RV1 is closed for backup, and the transition device of the vacuum on-load tap-changer is switched from odd-numbered gears. to even-numbered files.

Preferably, after the step of changing the moving contact of the action arm of the main transfer switch S1 from a to the static contact of b, it also includes:

The odd-numbered load current flows through the auxiliary transfer switch S2 and the load current circuit breaker MV, and is output through the load current circuit breaker MV. At the same time, the transition resistance R1 and the circulating current circuit breaker RV1 are connected in parallel, and are output through the b contact of the main transfer switch S1.

Preferably, after the step of extinguishing the arc in the load current vacuum circuit breaker MV, the method further includes:

The odd-numbered load current flows through the transition resistor R1, the circulating vacuum circuit breaker RV1 and the b contact output of the main transfer switch S1 in sequence.

Preferably, it also includes:

When the gear position of the on-load tap-changer is in an even-numbered tap, the moving contact of the main transfer switch S1 is connected to the static contact c, and the moving contact of the auxiliary transfer switch S2 is connected to the static contact f. ;

The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact c of the main transfer switch through the switch arm of S1, and the auxiliary transfer switch S2 is connected in parallel. f contact, load current circuit breaker MV output.

The application also provides a conversion method for a vacuum on-load tap-changer transition device, including:

Turn the moving contact of the action arm of the main transfer switch S1 from c to the static contact of d, disconnect the load current vacuum circuit breaker MV, and generate an arc;

When the arc in the load current vacuum circuit breaker MV is extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection f static contact to the connection e static contact;

Close the load current vacuum circuit breaker MV, and the transition device connects the even-numbered gear and the odd-numbered gear at the same time to form a bridge, generate a circulating current, and transfer the load current from the even-numbered gear to the odd-numbered gear;

Disconnect the circulating vacuum circuit breaker RV2 to generate an arc;

When the arc in the circulating vacuum circuit breaker RV2 is extinguished, the moving contact of the action arm of the main transfer switch S1 is changed from d to the static contact a, and the circulating vacuum circuit breaker RV2 is closed at the same time for standby, completing the transition of the vacuum on-load tap changer from the even-numbered gear. to odd-numbered files.

Preferably, after the step of changing the moving contact of the main transfer switch S1 from the moving arm of the action arm to the static contact of d, it further includes:

The even-numbered load current flows through the auxiliary transfer switch S2 and the load current circuit breaker MV, and is output through the load current circuit breaker MV. At the same time, the transition resistance R2 and the circulating current circuit breaker RV2 are connected in parallel, and output through the d contact of the main transfer switch S1.

Preferably, after the step of extinguishing the arc in the load current vacuum circuit breaker MV, the method further includes:

The even-numbered load current flows through the transition resistor R2, the circulating vacuum circuit breaker RV2 and the d-contact output of the main transfer switch S1 in sequence.

The present application provides a vacuum on-load tap changer transition device, comprising: a main transfer switch S1, an auxiliary transfer switch S2, circulating current vacuum circuit breakers RV1, RV2, load current vacuum circuit breakers MV and transition resistances R1, R2; Compared with the existing structural transition circuit, it can significantly reduce the moving parts in the tap changer, reduce the complexity of the mechanical structure, balance the switching capacity of the main vacuum circuit breaker and the auxiliary vacuum circuit breaker, and improve the electrical life of the entire vacuum on-load tap-changer. The problem of the complex mechanical structure of the existing device and the low electrical life of the vacuum on-load tap-changer is solved.

Description of drawings

1 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in this application;

2 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

3 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

4 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

5 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

6 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

7 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

8 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

9 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

10 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

11 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

12 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

13 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

14 is a schematic diagram of the transition of the vacuum type on-load tap-changer transition device shown in the present application;

Fig. 15 is a schematic diagram of the process of switching from N→N+1 of the vacuum type on-load tap-changer transition device shown in the present application;

FIG. 16 is a schematic diagram of the transition from N+1→N conversion procedure of the vacuum type on-load tap-changer transition device shown in the present application;

Fig. 17 is another switching device of the on-load tap-changer of the present application;

Detailed ways

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar promotions without violating the connotation of the present application. Therefore, the present application is not limited by the specific implementation disclosed below.

The present application provides a vacuum on-load tap-changer transition device, the structure of which is shown in Figure 1, including: a main transfer switch S1, an auxiliary transfer switch S2, circulating vacuum circuit breakers RV1, RV2, load current vacuum circuit breaker MV and transition Resistors R1, R2;

The main transfer switch S1 has a total of four static contacts a, b, c, d; electrodes a and c are respectively connected to the on-load tap-changer tap selector odd-numbered (Odd Tap) and even-numbered (Even Tap), b, The d electrodes are respectively connected to the circulating current vacuum circuit breakers RV1 and RV2. The vacuum circuit breakers RV1 and RV2 are respectively connected to the transition resistances R1 and R2. The transition resistances R1 and R2 are respectively connected to the on-load switch tap selector odd-numbered and even-numbered gears, and the S1 transfer switch The fixed end of the action arm is connected to the neutral point of the transformer, and the moving contact can be rotated to connect the four static contacts a, b, c, and d;

Auxiliary transfer switch S2 has two static contacts, e and f; electrodes e and f are respectively connected to the on-load tap-changer tap selector Odd Tap and Even Tap, and the S2 switch action arm is fixed The terminal is connected to the neutral point of the transformer through the load current vacuum circuit breaker MV, and the moving contact can be rotated to select the two static contacts e and f;

The circulating vacuum circuit breaker RV1 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from the odd gear to the even gear;

The circulating current vacuum circuit breaker RV2 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from an even gear to an odd gear;

The load current vacuum circuit breaker MV is used to cut off the load current when the tap changer transition device is switched from odd to even and/or even to odd.

The fixed end of the moving contact of the main transfer switch S1 and one end of the load current vacuum circuit breaker MV are both connected to the neutral point of the transformer to output current.

When the gear position of the on-load tap-changer is in an odd-numbered tap, the moving contact of the action arm of the main transfer switch S1 conducts with the static contact a, and the moving contact of the action arm of the auxiliary transfer switch S2 conducts with the static contact e. Pass;

The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact a of the main transfer switch S1 through the S1 switch action arm, and the auxiliary transfer switch S2 is connected in parallel at the same time. e contact, load current circuit breaker MV output.

When the tap changer is switched from an odd-numbered gear to an even-numbered gear, a method for converting a transition device for a vacuum on-load tap-changer includes:

Turn the moving contact of the main transfer switch S1 action arm from a to the static contact b, the odd-numbered load current flows through the auxiliary transfer switch S2 and the load current circuit breaker MV, and is output through the load current circuit breaker MV, and the transition resistance R1 is connected in parallel with the The circulating current circuit breaker RV1 is output through the b contact of the main transfer switch S1. The load current vacuum circuit breaker MV is disconnected to generate an arc. After the arc is extinguished, the odd-numbered load current I _N flows through the transition resistor R1, the circulating current vacuum circuit breaker RV1 and the b contact of the main transfer switch S1. Recovery voltage U _MV at both ends of circuit breaker MV _=IN ×R1;

When the arc in the load current vacuum circuit breaker MV is completely extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection e static contact to the connection f static contact, and the odd-numbered load current I _N flows through the transition resistor R1 and the circulating current vacuum circuit breaker in turn. RV1 and the b contact output of the main transfer switch S1;

偶数档负载电流I_N流经辅助转换开关S2的f触头和负载电流真空断路器MV输出；流经所述负载电流真空断路器MV的电流I_MV＝I_N+I_RV1；其中，所述U_S为有载分接开关级电压；Close the load current vacuum circuit breaker MV, transfer the load current from the odd-numbered gear to the even-numbered gear, and the transition device connects the odd-numbered gear and the even-numbered gear at the same time to form a bridge and generate a circulating current

The even-numbered load current I _N flows through the f contact of the auxiliary transfer switch S2 and the load current vacuum circuit breaker MV output; the current I _{MV =} IN +I _RV1 flowing through the load current vacuum circuit breaker MV; wherein, the said U _S is the on-load tap-changer stage voltage;

Disconnect the circulating vacuum circuit breaker RV1 to generate an arc; the even-numbered load current I _N flows through the f contact of the auxiliary transfer switch S2 and the load current vacuum circuit breaker MV output; the recovery voltage at both ends of the circulating vacuum circuit breaker RV1 is U _RV1 = _US ;

When the arc in the circulating vacuum circuit breaker RV1 is completely extinguished, the moving contact of the action arm of the main transfer switch S1 is transferred from b to the static contact c, and the circulating vacuum circuit breaker _RV1 is closed at the same time. The static contact c is connected to the neutral point output through the S1 switch action arm, and at the same time, the auxiliary transfer switch S2f contact and the load current circuit breaker MV output are connected in parallel. Convert to even-numbered files.

When the gear position of the on-load tap-changer is in an even-numbered tap, the moving contact of the main transfer switch S1 is connected to the static contact c, and the moving contact of the auxiliary transfer switch S2 is connected to the static contact f. ; The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact c of the main transfer switch through the switch arm of S1, and the auxiliary transfer switch S2 is connected in parallel. The f contact, load current circuit breaker MV output.

When the tap changer is switched from an even-numbered gear to an odd-numbered gear, a method for converting a transition device for a vacuum on-load tap-changer includes:

Turn the moving contact of the action arm of the main transfer switch S1 from c to the static contact of d, the even-numbered load current flows through the auxiliary transfer switch S2 and the load current circuit breaker MV, and outputs through the load current circuit breaker MV, and the transition resistance R2 is connected in parallel with the The circulating current circuit breaker RV2 is output through the d contact of the main transfer switch S1. The load current vacuum circuit breaker MV is disconnected to generate an arc; after the arc is extinguished, the even-numbered load current I _N flows through the transition resistance R2, the circulating vacuum circuit breaker RV2 and the d contact of the main transfer switch S1 in turn, and the load vacuum is output. Recovery voltage U _MV at both ends of circuit breaker MV _=IN ×R2;

When the arc in the load current vacuum circuit breaker MV is completely extinguished, the action arm of the auxiliary transfer switch S2 is switched from connecting the static contact f to the static contact e; after the arc in V is completely extinguished, the action arm of the auxiliary transfer switch S2 is connected to the static contact f The contact is switched to the static contact connected to e, and the even-numbered load current I _N flows through the transition resistor R2, the circulating vacuum circuit breaker RV2 and the d contact output of the main transfer switch S1 in turn.

奇数档负载电流I_N流经辅助转换开关S2的e触头和负载电流真空断路器MV输出；流经所述负载电流真空断路器MV的电流I_MV＝I_N+I_RV2；其中，所述U_s为有载分接开关级电压。Close the load current vacuum circuit breaker MV, transfer the load current from the even-numbered gear to the odd-numbered gear, and the transition device connects the even-numbered gear and the odd-numbered gear at the same time to form a bridge and generate a circulating current

The odd _- numbered load current IN flows through the e-contact of the auxiliary transfer switch S2 and the output of the load current vacuum circuit breaker MV; the current I _{MV =} IN +I _RV2 flowing through the load current vacuum circuit breaker MV; wherein, the U _s is the on-load tap-changer stage voltage.

Disconnect the circulating vacuum circuit breaker RV2 to generate an arc; the odd-numbered load current I _N flows through the e contact of the auxiliary transfer switch S2 and the load current vacuum circuit breaker MV output; the recovery voltage at both ends of the circulating vacuum circuit breaker RV2 is U _RV2 = _US .

When the arc in the circulating vacuum circuit breaker RV2 is completely extinguished, the moving contact of the action arm of the main transfer switch S1 is transferred from d to the static contact a, and the circulating vacuum circuit breaker _RV2 is closed at the same time. The static contact a is connected to the neutral point output through the switch arm of S1, and the e contact of the auxiliary transfer switch S2 and the MV output of the load current circuit breaker are connected in parallel. The tap-change operation is completed, and the transition device of the vacuum on-load tap-changer is completed from the even-numbered gear to the odd-numbered gear.

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

Compared with the prior art, the vacuum type on-load tap-changer transition device proposed in the present application has only two mechanical transfer switches in the circuit, which reduces the number of moving parts and reduces the complexity of the mechanical structure; the tasks of passing and cutting off the circulating current are composed of two The circuit transition resistances R1 and R2 and the circulating vacuum circuit breakers RV1 and RV2 take turns to undertake the switching tasks, sharing the switching task of only one auxiliary vacuum bubble in the existing topology; and adding a transition resistance, the transition resistance can be rotated to reduce the transition resistance. The temperature rise can prevent the transformer oil from decomposing and gas production and the insulation performance being reduced due to the high temperature of the transition resistance, greatly improving the electrical life of the entire switch, and solving the problems of the complex mechanical structure of the existing device and the low electrical life of the vacuum on-load tap-changer.

1. The structure of a vacuum on-load tap-changer transition device

In this embodiment, the vacuum type on-load tap changer transition device includes a main transfer switch S1, an auxiliary transfer switch S2, circulating current vacuum circuit breakers RV1, RV2, load current vacuum circuit breakers MV and transition resistors R1, R2.

(1) The main transfer switch S1 has a total of 4 static contacts: electrodes a and c are respectively connected to the odd and even gears of the tap selector of the tap changer, electrodes b and d are respectively connected to the two circulating vacuum circuit breakers RV1 and RV2, and the two vacuum The circuit breaker is connected with two transition resistors R1 and R2 respectively, and the odd-numbered and even-numbered gears of the switch tap selector are respectively connected through the transition resistors. The fixed end of the action arm of the S1 transfer switch is connected to the neutral point of the transformer, and the moving contact can be rotated to select the connection a , b, c, d four static contacts.

(2) The auxiliary transfer switch has 2 static contacts: the e and f electrodes are respectively connected to the odd-numbered gear (Odd Tap) and the even-numbered gear (Even Tap) of the tap selector of the tap changer, and the fixed end of the S2 switch action arm passes the load current The vacuum circuit breaker MV is connected to the neutral point of the transformer, and the moving contact can be rotated to connect the two static contacts e and f.

(3) The circulating vacuum circuit breaker RV1 is used to cut off the circulating current between the two gears when the odd gear is switched to the even gear, and the circulating vacuum circuit breaker RV2 is used to cut off the circulating current between the two gears when the even gear is switched to the odd gear.

(4) The load current vacuum circuit breaker is used to cut off the load current when the odd-numbered gear is switched to the even-numbered gear and the even-numbered gear is switched to the odd-numbered gear.

(5) When the gear position of the on-load tap-changer is in an odd-numbered tap, the moving contact of the action arm of the main transfer switch S1 is conductive with the static contact a, and the moving contact of the action arm of the auxiliary transfer switch S2 is in contact with the static contact Head e is turned on. The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact a of the main transfer switch through the switch arm of S1, and the auxiliary transfer switch S2e is connected in parallel. Head, load current circuit breaker MV output.

2. Conversion method of vacuum on-load tap-changer transition device

It is assumed that the initial position of the change-over selector of the tap selector of the on-load tap-changer remains unchanged, and the gear number of the on-load tap-changer is consistent with the label of the tap selector contact group. An odd-numbered gear N rises to an even-numbered gear N+1.

(1) When the gear position of the on-load tap-changer is in an odd-numbered tap, as shown in Figure 1, the moving contact of the action arm of the main transfer switch S1 is connected to the static contact a, and the moving contact of the action arm of the auxiliary transfer switch S2 The head and the static contact e are conducting. The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact a of the main transfer switch through the switch arm of S1, and the auxiliary transfer switch S2e is connected in parallel. Head, load current circuit breaker MV output.

1. When the tap selector is switched from an odd tap to an even tap, the specific operation methods include:

(1) As shown in Figure 2, the moving contact of the main transfer switch S1 is changed from a to the static contact b of the action arm, and the odd _- numbered load current IN flows through the auxiliary transfer switch S2 and the load current circuit breaker MV for output, At the same time, the transition resistance R1 and the circulating current circuit breaker RV1 are connected in parallel, and are output through the contact of the main transfer switch S1b.

(2) As shown in Figure 3, disconnect the load current vacuum circuit breaker MV to generate an arc; after the arc is extinguished, the odd-numbered load current I _N flows through the transition resistance R1, the circulating current vacuum circuit breaker RV1 and the main transfer switch in turn S1b contact output, the recovery voltage U MV at both ends of the load vacuum circuit breaker _{MV =IN} ×R1;

(3) As shown in Figure 4, after the arc in the load current vacuum circuit breaker MV is completely extinguished, the action arm of the auxiliary transfer switch S2 is switched from the static contact e connected to the static contact f, and the odd-numbered load current I _N flows through the Transition resistance R1, circulating vacuum circuit breaker RV1 and main transfer switch S1b contact output;

(4) As shown in Figure 5, the load current vacuum circuit breaker MV is closed, and the transition circuit is connected to the odd-numbered gear and the even-numbered gear at the same time to form a bridge, and a circulating current I _RV1 =U _s /R1 is generated; at this time, the load current is changed by the odd-numbered gear Transfer to the even-numbered gear, and the even-numbered load current I _N flows through the contact of the auxiliary transfer switch S2f and the output of the load current vacuum circuit breaker MV; the current flowing through the load current vacuum circuit breaker MV I _{MV =} IN +I _RV1 ; wherein , the U _S is the on-load tap-changer stage voltage;

(5) As shown in Figure 6, the circulating vacuum circuit breaker RV1 is disconnected to generate an arc; the even-numbered load current I _N flows through the contact of the auxiliary transfer switch S2f and the load current vacuum circuit breaker MV is output; the circulating current vacuum circuit breaker RV1 The recovery voltage at both ends is U _RV1 =U _S ;

(6) As shown in Figure 7, after the arc in the circulating vacuum circuit breaker RV1 is completely extinguished, the moving contact of the main transfer switch S1 is moved from b to the static contact c, and the circulating vacuum circuit breaker RV1 is closed at the same time. The load current I _N is connected to the neutral point output through the static contact c of the main transfer switch through the S1 switch action arm, while the auxiliary transfer switch S2f contact and the load current circuit breaker MV are output in parallel. The tap-change operation is over, and the changeover switch completes the pressure regulation from odd-numbered gears to even-numbered gears.

2. When the tap selector is switched from an odd-numbered tap to an even-numbered tap, the schematic diagram of the transition circuit switching procedure is shown in Figure 15.

(2) When the gear position of the on-load tap-changer is in an even-numbered tap, as shown in Figure 8, the moving contact of the action arm of the main transfer switch S1 is connected to the static contact c, and the moving contact of the action arm of the auxiliary transfer switch S2 The head and the static contact f are conducting. The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact c of the main transfer switch through the S1 switch action arm, and the auxiliary transfer switch S2f is connected in parallel. Head, load current circuit breaker MV output.

1. When the tap selector is switched from an even tap to an odd tap, the specific operation methods include:

(1) As shown in FIG. 9, the moving contact of the main transfer switch S1 is moved from c to the static contact of d, and the even _- numbered load current IN flows through the auxiliary transfer switch S2 and the load current circuit breaker MV for output, At the same time, the transition resistance R2 and the circulating current circuit breaker RV2 are connected in parallel, and are output through the contact of the main transfer switch S1d.

(2) As shown in Figure 10, disconnect the load current vacuum circuit breaker MV to generate an arc; after the arc is extinguished, the even-numbered load current I _N flows through the transition resistance R2, the circulating vacuum circuit breaker RV2 and the main transfer switch in turn S1d contact output, the recovery voltage U _MV at both ends of the load vacuum circuit breaker MV ₌ IN ×R2;

(3) As shown in Figure 11, after the arc in the load current vacuum circuit breaker MV is completely extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection f static contact to the e static contact, and the even-numbered load current I _N flows through the Transition resistance R2, circulating vacuum circuit breaker RV2 and main transfer switch S1d contact output;

(4) As shown in Figure 12, the load current vacuum circuit breaker MV is closed, and the transition circuit is connected to the even-numbered gear and the odd-numbered gear at the same time to form a bridge, and a circulating current I _RV2 =U _s /R2 is generated; at this time, the load current is changed by the even-numbered gear. Transfer to the odd-numbered gear, the odd _- numbered load current IN flows through the contact of the auxiliary transfer switch S2e and the output of the load current vacuum circuit breaker MV; the current I _{MV =} IN +I _RV2 flowing through the load current vacuum circuit breaker MV; wherein , the U _S is the on-load tap-changer stage voltage;

(5) As shown in Figure 13, the circulating vacuum circuit breaker RV2 is disconnected to generate an arc; the odd-numbered load current I _N flows through the contact of the auxiliary transfer switch S2e and the load current vacuum circuit breaker MV output; the circulating current vacuum circuit breaker RV2 The recovery voltage at both ends is U _RV2 =U _S ;

(6) As shown in Figure 14, after the arc in the circulating vacuum circuit breaker RV2 is completely extinguished, the moving contact of the main transfer switch S1 is moved from d to the static contact a, and the circulating vacuum circuit breaker RV2 is closed for standby at the same time. The load current I _N is connected to the neutral point output through the static contact a of the main transfer switch through the S1 switch action arm, while the auxiliary transfer switch S2e contact and the load current circuit breaker MV are output in parallel. The tap-change operation is over, and the changeover switch completes the voltage regulation from the even-numbered gear to the odd-numbered gear.

2. When the tap selector is switched from an even tap to an odd tap, the schematic diagram of the transition circuit switching procedure is shown in Figure 16.

3. The tasks of the vacuum circuit breaker of the vacuum on-load tap-changer transition device in this embodiment are shown in the following table:

Among them, N is the switching times of the tap changer gear, I _N is the load current; Us is the voltage of the on-load tap changer; R1, R2 are the transition resistances.

4. FIG. 17 shows a variant embodiment of the on-load tap-changer according to the present application. In this case, the auxiliary contact S2 according to the present application is not designed as a single-arm contact, but as a double-arm contact. This embodiment achieves the balance of the force on the action arm of the switch without changing its function and effect.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should Modifications or equivalent replacements are made to the specific embodiments, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention shall all be included in the scope of the claims of the present invention.

Claims (8)

1. a vacuum on-load tap changer transition device, is characterized in that, comprises: main transfer switch S1, auxiliary transfer switch S2, circulating current vacuum circuit breaker RV1, RV2, load current vacuum circuit breaker MV and transition resistance R1, R2; The main transfer switch S1 has a total of four static contacts a, b, c and d; electrodes a and c are respectively connected to the on-load tap-changer tap selector odd-numbered gear and even-numbered gears, and electrodes b and d are respectively connected to the circulating current vacuum circuit breaker RV1, RV2, circulating vacuum circuit breakers RV1, RV2 are respectively connected with transition resistance R1, R2, transition resistance R1, R2 are respectively connected with the on-load tap changer tap selector odd-numbered gear and even-numbered gear, the main transfer switch S1 action arm is fixed The terminal is connected to the neutral point of the transformer, and the moving contact can be rotated to select the four static contacts a, b, c, and d; Auxiliary transfer switch S2 has two static contacts, e and f; electrodes e and f are respectively connected to the on-load tap-changer tap selector for odd-numbered gears and even-numbered gears, and the fixed end of the action arm of the auxiliary transfer switch S2 is vacuum-disconnected by the load current. The transformer MV is connected to the neutral point of the transformer, and the moving contact can be rotated to select the two static contacts e and f; The circulating vacuum circuit breaker RV1 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from the odd gear to the even gear; The circulating current vacuum circuit breaker RV2 is used to cut off the circulating current between the two gears when the tap changer transition device is switched from an even gear to an odd gear; The load current vacuum circuit breaker MV is used to cut off the load current when the tap changer transition device is switched from odd to even and/or even to odd. 2 . The transition device according to claim 1 , wherein the fixed end of the moving contact of the main transfer switch S1 and one end of the load current vacuum circuit breaker MV are both connected to the neutral point of the transformer to output current. 3 . 3. The transition device of claim 1, further comprising: When the gear position of the on-load tap-changer is in an odd-numbered tap, the moving contact of the action arm of the main transfer switch S1 conducts with the static contact a, and the moving contact of the action arm of the auxiliary transfer switch S2 conducts with the static contact e. Pass; The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the static contact a of the main transfer switch S1 through the action arm of the main transfer switch S1, and the auxiliary conversion is connected in parallel at the same time. E contact of switch S2, load current vacuum circuit breaker MV output. 4. a conversion method of vacuum on-load tap changer transition device as claimed in claim 1, is characterized in that, comprising: Turn the moving contact of the action arm of the main transfer switch S1 from a to the static contact of b, the odd-numbered load current flows through the auxiliary transfer switch S2 and the load current vacuum circuit breaker MV, and is output through the load current vacuum circuit breaker MV, and the transition resistance is connected in parallel at the same time. R1 and circulating vacuum circuit breaker RV1 are output through the b static contact of the main transfer switch S1; Disconnect the load current vacuum circuit breaker MV, cut off the load current, and generate arc; When the arc in the load current vacuum circuit breaker MV is extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection e static contact to the connection f static contact; Close the load current vacuum circuit breaker MV, and transfer the load current from the odd-numbered gear to the even-numbered gear, and the transition device connects the odd-numbered gear and the even-numbered gear at the same time to form a bridge and generate a circulating current; Disconnect the circulating vacuum circuit breaker RV1, cut off the circulating current, and generate an arc; When the arc in the circulating current vacuum circuit breaker RV1 is extinguished, the moving contact of the action arm of the main transfer switch S1 is changed from b to the c static contact, and at the same time, the circulating current vacuum circuit breaker RV1 is closed for backup, and the transition device of the vacuum on-load tap-changer is switched from odd-numbered gears. to even-numbered files. 5. The method according to claim 4, characterized in that, after the step of extinguishing the arc in the load current vacuum circuit breaker MV, further comprising: The odd-numbered load current flows through the transition resistor R1, the circulating vacuum circuit breaker RV1 and the b static contact of the main transfer switch S1 in turn for output. 6. The method of claim 4, further comprising: When the gear position of the on-load tap-changer is in an even-numbered tap, the moving contact of the main transfer switch S1 is connected to the static contact c, and the moving contact of the auxiliary transfer switch S2 is connected to the static contact f. ; The load current vacuum circuit breaker MV is turned on, the circulating current vacuum circuit breakers RV1 and RV2 are turned on, the load current I _N is connected to the neutral point output through the main transfer switch static contact c through the main transfer switch S1 action arm, and the auxiliary transfer switch is connected in parallel at the same time. The f contact of S2, the load current vacuum circuit breaker MV output. 7. A conversion method of vacuum on-load tap changer transition device as claimed in claim 1, characterized in that, comprising: Turn the moving contact of the action arm of the main transfer switch S1 from c to the static contact of d, the even-numbered load current flows through the auxiliary transfer switch S2 and the load current vacuum circuit breaker MV, and is output through the load current vacuum circuit breaker MV, and the transition resistance is connected in parallel at the same time. R2 and circulating vacuum circuit breaker RV2 are output through the static contact d of the main transfer switch S1 to disconnect the load current vacuum circuit breaker MV and generate an arc; When the arc in the load current vacuum circuit breaker MV is extinguished, the action arm of the auxiliary transfer switch S2 is switched from the connection f static contact to the connection e static contact; Close the load current vacuum circuit breaker MV, and the transition device connects the even-numbered gear and the odd-numbered gear at the same time to form a bridge, generate a circulating current, and transfer the load current from the even-numbered gear to the odd-numbered gear; Disconnect the circulating vacuum circuit breaker RV2 to generate an arc; When the arc in the circulating vacuum circuit breaker RV2 is extinguished, the moving contact of the action arm of the main transfer switch S1 is changed from d to the static contact a, and the circulating vacuum circuit breaker RV2 is closed at the same time for standby, completing the transition of the vacuum on-load tap changer from the even-numbered gear. to odd-numbered files. 8. The method according to claim 7, characterized in that, after the step of extinguishing the arc in the load current vacuum circuit breaker MV, it further comprises: The even-numbered load current flows through the transition resistor R2, the circulating vacuum circuit breaker RV2 and the d static contact of the main transfer switch S1 and outputs in turn.

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