CN202678073U - On-load capacitance-adjusting switch with four fractures connected in series - Google Patents

Abstract

The utility model discloses an on-load capacitance-adjusting switch with four fractures connected in series. The switch adopts the structure that by arranging two transition contacts at a high-voltage part, four fractures connected in series are formed between high-voltage input contacts and high-voltage contacts, so that a higher switching voltage is evenly distributed to the four fractures formed by movable contacts and fixed contacts; each fracture voltage is lower than arc-quenching voltage, so that a capacitance-adjusting switch has a high on-load switching capability as well as a high insulation and withstand voltage level; the three phases of the high-voltage part are independently arranged; each the high-voltage input contact and the high-voltage contact of each phase are respectively arranged in an upper layer and a lower layer; and one transition contact and the high-voltage inputs as well as the other transition contact and the high-voltage contacts are both arranged in the same layer, so that the switch has a more simple structure, a more reasonable layout, more reliable operation, more convenient installation, and better arc quenching, insulation and withstand voltage effects.

Description

Series four-break on-load capacity regulating switch

technical field

The utility model belongs to the field of transformer switches, in particular to an on-load capacity regulating switch with four fractures connected in series. the

Background technique

Electric energy from the power plant to the user needs to be stepped up and down multiple times through the power transformer. Although the efficiency of the transformer itself is very high, its total loss is still very large due to the large number and large capacity. According to statistics, the total loss of transformers in my country accounts for about 10% of the system's power generation; and among the losses of medium and low-voltage power grids that account for 60% to 65% of the total loss of the power grid, about 70% of the losses are in distribution transformers. If the transformer loss can be reduced by 1%, tens of billions of kilowatt-hours of electricity can be saved every year. Due to the strong seasonality of rural power grid load and the large peak-to-valley difference in load, the loss of distribution transformers in rural power grids in my country is relatively large, resulting in a large waste of power resources. the

The on-load capacity-adjusting transformer is a transformer with two types of rated capacity. According to the size of the load, a special capacity-adjusting switch (divided into no-load capacity adjustment and on-load capacity adjustment) is used to change the connection mode of the winding to realize two types of transformers. Switching between different capacities (when the transformer has a large capacity, the winding on the high voltage side is D-connected, and when the capacity is small, it is Y-connected). The no-load loss and load loss of the capacity regulating transformer are lower, especially the total loss during light-load operation is much lower than that of other types of transformers with the same capacity. The off-load capacity-adjusting transformer has small capacity, low on-line controllability, and cannot adjust the capacity on-line. Generally, only seasonal adjustment is performed, and the adjustment will affect the user's power supply reliability. The on-load capacity regulating transformer can effectively solve and eliminate the above-mentioned problems and limitations of the existing off-load capacity regulating transformer, can automatically monitor and control in real time, and adjust the capacity reasonably according to the actual load size, thereby further expanding the scope of use of the capacity regulating transformer . To complete the switching task of the transformer winding when the transformer is loaded, the main technical difficulty lies in the reliable arc extinguishing of the high-voltage side contacts during the star-delta switching process. the

Contents of the invention

In order to solve the above-mentioned technical problems, the purpose of this utility model is to provide a series four-fracture on-load capacity regulating switch. The high-voltage part is provided with transition contacts to form four series fractures between the high-voltage input contact and the high-voltage contact. Such a high switching voltage is evenly distributed to the four fractures composed of moving contacts and fixed contacts, and the voltage of each fracture is lower than the arc-extinguishing voltage, and the switch has high load switching capacity and withstand voltage grade. the

In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

A series four-fracture on-load capacity regulating switch, including a motor, a fast mechanism, an insulating cylinder, a main shaft and a contact system, the contact system includes a low-voltage part and a high-voltage part; the contact system includes a moving contact installed on the main shaft and the fixed contact installed on the insulating cylinder; the high-voltage part of the contact system is divided into three phases, and each phase includes a high-voltage input contact and a high-voltage contact; the high-voltage input contact includes a high-voltage input movable contact and a high-voltage input The fixed contact, the high-voltage input movable contact includes a main contact and an auxiliary arc contact, the high-voltage input fixed contact includes a D-contact fixed contact and a Y-contact fixed contact; the high-voltage movable contact includes a high-voltage movable contact The high-voltage fixed contact includes a main contact and an auxiliary arc contact, and the high-voltage fixed contact includes a D-contact fixed contact and a Y-contact fixed contact; the high-voltage input contact and the high-voltage The contacts are arranged in upper and lower layers along the axial direction of the main shaft. The first transition contact is arranged on the same layer as the high-voltage input contact, which includes the first transition moving contact and the first transition fixed contact. The first transition moving contact The contacts include a main contact and an auxiliary arc contact, which includes a D fixed contact and a Y fixed contact, and a second transition contact is provided on the same layer as the high voltage contact, which includes a second transition dynamic contact and the second transitional fixed contact, the second transitional moving contact includes a main contact and an auxiliary arc contact, and the second transitional fixed contact includes a D-contact fixed contact and a Y-contact fixed contact; where , the main contact of the high-voltage input moving contact is electrically connected to the main contact of the first transitional moving contact, the auxiliary arcing contact of the high-voltage input moving contact is electrically connected to the auxiliary arcing contact of the first transitional moving contact, and the high-voltage The main contact of the moving contact is electrically connected to the main contact of the second transitional moving contact, the auxiliary arcing contact of the high-voltage moving contact is electrically connected to the auxiliary arcing contact of the second transitional moving contact, and the first transitional fixed contact The D contact fixed contact of the head is electrically connected with the D contact fixed contact of the second transition fixed contact, and the Y contact fixed contact of the first transition fixed contact is electrically connected with the Y contact fixed contact of the second transition fixed contact . the

For the convenience of wiring connection, preferably, the D-connection fixed contact and the Y-connection fixed contact of the high-voltage input fixed contact are connected through a conductive electrical connector. the

Preferably, the auxiliary arcing contact of the high voltage input moving contact is electrically connected to the auxiliary arcing contact of the first transition moving contact after being connected in series with the first transition resistor. the

Preferably, the auxiliary arcing contact of the high voltage moving contact is electrically connected to the auxiliary arcing contact of the second transition moving contact after being connected in series with the second transition resistor. the

Since the utility model adopts the above technical scheme, the high-voltage part forms four series fractures between the high-voltage input contact and the high-voltage contact by setting two transition contacts, so that a higher switching voltage is evenly distributed to The voltage of each fracture is lower than the arc-extinguishing voltage of the four openings composed of moving contacts and fixed contacts, so the capacity regulating switch has higher on-load switching capability and insulation withstand voltage level. The three phases of the high-voltage part are set independently, the high-voltage input contacts and high-voltage contacts of each phase are arranged in upper and lower layers, and the transition contacts are arranged in the same layer as the high-voltage input contacts and high-voltage contacts, so that the structure of the utility model It is simpler, more reasonable in layout, more reliable in operation, more convenient in installation, better in arc extinguishing and insulation withstand voltage. the

Description of drawings

Fig. 1 is the structural representation of embodiment 1;

Fig. 2 is the A-A sectional view of Fig. 1;

Fig. 3 is the B-B sectional view of Fig. 1;

Fig. 4 is the schematic diagram of A phase D connection of embodiment 1;

Fig. 5 is the A phase Y connection schematic diagram of embodiment 1;

Fig. 6 is a circuit diagram of the high voltage part of embodiment 1. the

Detailed ways

Below in conjunction with accompanying drawing, specific embodiment of the present utility model is described in detail. the

Example 1:

As shown in Figure 1, the four-interface on-load capacity regulating switch in series includes a housing 1, a motor 2, a fast mechanism 3, an insulating cylinder 5, a main shaft 4 and a contact system. The contact system includes a low-voltage part and a high-voltage part; the contact system includes a moving contact installed on the main shaft 4 and a fixed contact installed on the insulating cylinder 5; the low-voltage part of the contact system is divided into three-phase (A phase, B phase, C phase), each phase includes a low-voltage fixed contact 9, a low-voltage moving contact 10 and a low-voltage transition resistor 11; the high-voltage part of the contact system is divided into three phases (A phase, B phase, C phase Phase), as shown in Figure 2 and Figure 3, each phase includes high-voltage input contacts and high-voltage contacts, high-voltage input contacts include high-voltage input moving contacts and high-voltage input fixed contacts, high-voltage input moving contacts include a main contact Head 81 and an auxiliary arc contact 811, the high-voltage input fixed contact includes a D-contact fixed contact 61 and a Y-contact fixed contact 62, and the two are connected through a conductive electrical connector 12; the high-voltage input includes a high-voltage The moving contact and the high-voltage fixed contact, the high-voltage moving contact includes a main contact 84 and an auxiliary arc contact 841, and the high-voltage fixed contact includes a D-contact fixed contact 67 and a Y-contact fixed contact 68; The high-voltage input contacts and the high-voltage contacts are arranged in upper and lower layers along the axis of the main shaft 4, and the first transition contacts are arranged on the same layer as the high-voltage input contacts. The first transition contacts include the first transition movable contact and the second transition contact. A transition fixed contact, the first transition movable contact includes a main contact 82 and an auxiliary arc contact 821, the first transition fixed contact includes a D contact fixed contact 63 and a Y contact fixed contact 64, and The high voltage contact is provided with a second transition contact on the same layer, the second transition contact includes a second transition moving contact and a second transition fixed contact, the second transition moving contact includes a main contact 83 and an auxiliary arc contact Head 831, the second transitional fixed contact includes a D contact fixed contact 65 and a Y contact fixed contact 66; wherein, as shown in Figure 4 and Figure 5, the main contact 81 of the high voltage input movable contact is connected to the first The main contact 82 of the transitional moving contact is electrically connected, the auxiliary arcing contact 811 of the high-voltage input moving contact is connected in series with the first transition resistor 71, and is electrically connected with the auxiliary arcing contact 821 of the first transitional moving contact, and the high-voltage moving contact The main contact 84 of the high-voltage moving contact is electrically connected to the main contact 83 of the second transitional moving contact, and the auxiliary arcing contact 841 of the high-voltage moving contact is connected with the auxiliary arcing contact 831 of the second transitional moving contact in series with the second transitional resistor 72 Electrical connection, the D contact fixed contact 63 of the first transition fixed contact is electrically connected to the D contact fixed contact 65 of the second transition fixed contact, and the Y contact fixed contact 64 of the first transition fixed contact is connected to the second transition fixed contact. The Y contact fixed contact 66 of the fixed contact is electrically connected. The above-mentioned conductive electrical connector 12 is a metal connecting piece. the

Fig. 6 is a circuit diagram of the high-voltage part of this embodiment, wherein Ar is a transformer winding, X1, X2, X3 and X4 are switch breaks, and R1 and R2 are transition resistors. Taking phase A as an example, when D is connected, as shown in Figure 4, the main contact 81 of the high-voltage input movable contact is connected to the D-contact fixed contact 61 of the high-voltage input fixed contact, and the main contact of the first transitional movable contact The head 82 is connected with the D contact fixed contact 63 of the first transition fixed contact, and the D contact fixed contact 63 of the first transition fixed contact is connected with the D contact fixed contact 65 of the second transition fixed contact through a wire, The main contact 83 of the second transitional moving contact is connected with the D-contact fixed contact 65 of the second transitional fixed contact, and the main contact 84 of the high-voltage moving contact is connected with the D-contact fixed contact 67 of the high-voltage fixed contact. When switching, the main shaft rotates, the main contact of each moving contact is out of contact with the fixed contact of D, and the auxiliary arc contact of each moving contact is in contact with the fixed contact of D until the main contact is fixed with Y The contacts contact to realize Y connection, as shown in Figure 5, at this time, the main contact 81 of the high-voltage input movable contact is connected with the Y-connected fixed contact 62 of the high-voltage input fixed contact, and the first transitional movable contact The main contact 82 is connected with the Y-connected fixed contact 64 of the first transitional fixed contact, and the Y-connected fixed contact 64 of the first transitional fixed contact is connected with the Y-connected fixed contact 66 of the second transitional fixed contact through a wire connection, the main contact 83 of the second transitional moving contact is connected with the Y-contact fixed contact 66 of the second transitional fixed contact, the main contact 84 of the high-voltage moving contact is connected with the Y-contact fixed contact of the high-voltage fixed contact 68 is connected. It can be seen from the above that the high-voltage input contact, the high-voltage contact, the first transition contact, and the second transition contact constitute four switch openings X1, X2, X3, and X4. the

The utility model has the following characteristics:

(1) For a 10kV single-break on-load capacity regulating switch, the switching voltage of the transformer winding is as high as 5770V during Y-D conversion. Although, single-break contacts are particularly difficult to extinguish. In order to ensure the problem of reliable arc extinguishing of the on-load capacity regulating switch, the technology of the utility model is to set the contact fracture of the on-load capacity regulating switch into a structure of four fractures in series. When four fractures in series are broken, an arc is generated on each fracture. When the current crosses zero, the recovery voltage of each fracture is greatly reduced, which is conducive to the extinguishment of the arc between the fractures; and only when the quadruple fractures are re-ignited at the same time, can the arc be restarted, which is obviously much more difficult than the single fracture, so the extinguishing Arc ability enhanced. The four fractures in series pass the same current (including the circulation of the transition circuit), so the burning loss on the contacts of the four fractures is basically the same, so the mechanism can maintain balance for a long time during operation;

(2) In order to realize the on-load Y-D conversion of the capacity regulating switch. The utility model adopts a single-resistance transition circuit with light contact switching task, which is beneficial to improve the electrical life of the electric auxiliary arc contact and reduce the number of electric auxiliary arc contacts in the transition circuit;

(3) The applicable "level voltage" of the utility model is 4000-6000V. Each phase adopts two contact layers, three phases are provided with six contact layers in total, and the two contact layers of each phase are connected in series on the circuit. Therefore, the contact structure can be combined with building blocks, which is compact and simple;

(4) The on-load capacity regulating switch of this utility model includes a fixed contact, a moving contact, an insulating cylinder, an operating mechanism and a fast mechanism, etc., and the three-phase six high-voltage moving contacts are installed on the insulating main shaft from top to bottom, and There is no electrical connection between the moving contact layers, and transition resistors are connected at both ends of the transition electrical auxiliary arc contacts of each layer; the six high-voltage fixed contacts are installed on the insulating cylinder around the six-layer high-voltage moving contacts, each There is an electrical connection outside the cylinder between the fixed contacts of the phase two layers. The three-phase low-voltage moving contact is also installed on the common insulating main shaft, and the low-voltage fixed contact is also installed on the common insulating cylinder around the low-voltage moving contact, and the high and low voltage contacts share an oil chamber. Therefore, the structure of the on-load capacity regulating switch is simple, and the manufacturing cost is low. the

Claims (4)

1. the loaded capacity-regulated switch of four fractures of connecting comprises motor (2), quick mechanism (3), insulating cylinder (5), main shaft (4) and contact system, and described contact system comprises low-pressure section and high-pressure section; Described contact system comprises the moving contact that is installed on the main shaft (4) and the contact of deciding that is installed on the insulating cylinder (5); Described contact system high-pressure section is divided into three-phase, every high input voltage contact and high-voltage contact of comprising mutually, it is characterized in that, described high input voltage contact comprises that high input voltage moving contact and high input voltage decide contact, the high input voltage moving contact comprises a main contact (81) and an auxiliary arcing contact (811), and high input voltage is decided contact and comprised that a D connects and decide contact (61) and a Y and connect and decide contact (62); Described high-voltage contact comprises high pressure moving contact and high compression set contact, and the high pressure moving contact comprises a main contact (84) and an auxiliary arcing contact (841), and high compression set contact comprises that a D connects to be decided contact (67) and a Y and connect and decide contact (68); Described high input voltage contact and high-voltage contact are axially divided along main shaft (4), lower two-layer layout, be provided with the First Transition contact with the high input voltage contact with layer, the First Transition contact comprises that First Transition moving contact and First Transition decide contact, the First Transition moving contact comprises a main contact (82) and an auxiliary arcing contact (821), First Transition is decided contact and is comprised that a D connects and decide contact (63) and a Y and connect and decide contact (64), be provided with the second transition contact with high-voltage contact with layer, the second transition contact comprises that the second transition moving contact and the second transition decide contact, the second transition moving contact comprises a main contact (83) and an auxiliary arcing contact (831), and the second transition is decided contact and comprised that a D connects and decide contact (5) and a Y and connect and decide contact (66); Wherein, the main contact of high input voltage moving contact (81) is electrically connected with the main contact (82) of First Transition moving contact, the auxiliary arcing contact (811) of high input voltage moving contact and the electrical connection of the auxiliary arcing contact (821) of First Transition moving contact, the main contact of high pressure moving contact (84) is electrically connected with the main contact (83) of the second transition moving contact, the auxiliary arcing contact (841) of high pressure moving contact and the electrical connection of the auxiliary arcing contact (831) of the second transition moving contact, the D that First Transition is decided contact connects and decides contact (63) and the second transition and decide the D of contact and connect and decide contact (65) electrical connection, and the Y that First Transition decide contact connects and decides contact (64) and the second transition and decide the Y of contact and connect and decide contact (66) and be electrically connected.

2. the loaded capacity-regulated switch of series connection four fractures according to claim 1 is characterized in that, the D that described high input voltage is decided contact connects and decides contact (61) and be connected with Y and decide contact (62) and connect by conduction gas connector (12).

3. the loaded capacity-regulated switch of series connection four fractures according to claim 1, it is characterized in that auxiliary arcing contact (811) the series connection First Transition resistance (71) of described high input voltage moving contact auxiliary arcing contact (821) rear and the First Transition moving contact is electrically connected.

4. the loaded capacity-regulated switch of series connection four fractures according to claim 1 is characterized in that, the auxiliary arcing contact (831) with the second transition moving contact behind auxiliary arcing contact (841) series connection second transition resistance (72) of described high pressure moving contact is electrically connected.

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