CN201563003U

CN201563003U - Dual-power switching device for air-cooled control box of large-size power transformer

Info

Publication number: CN201563003U
Application number: CN2009203135537U
Authority: CN
Inventors: 王文英; 程从明; 赵峰; 石建; 王建明; 丁领
Original assignee: Baoding Tianwei Group Co Ltd
Current assignee: Baoding Tianwei Group Co Ltd
Priority date: 2009-10-29
Filing date: 2009-10-29
Publication date: 2010-08-25
Anticipated expiration: 2019-10-29

Abstract

The utility model relates to a dual-power switching device for an air-cooled control box of a large-size power transformer, which belongs to the technical field of manufacturing transformers. The technical scheme is as follows: a power and monitor loop comprises two power supplies (I and II), two groups of alternating-current contactor contacts (KMM1 and KMM2), four order relays (KX1, KX2, KX3 and KX4) and a bus connection switch (QM). An alternating-current control circuit comprises two control circuits for respectively controlling two three-phase power supplies, wherein each control circuit comprises an alternating-current contactor, a middle relay, a time relay and a control node. A direct-current control circuit comprises a change-over switch (SAM1), transformer breaker auxiliary contacts (QF1, QF2 and QF3) and the middle relay. The utility model not only can cut off the faulty power supply and automatically switch on a spare power supply when the power supply is in fault, but also can monitor easily-damaged elements in the circuit so as to prevent that the transformer trips due to the power shutdown of the cooling system as the power supply can not be switched due to the faulty of the electric elements. The stability of the power system is reliably ensured.

Description

The air-cooled control cabinet double-power supply switching device of large-scale power transformer

Affiliated technical field:

The utility model relates to the air-cooled control cabinet double-power supply switching device of large-scale power transformer, belongs to technical field of transformer manufacturing.

Background technology:

The cooling device of high-power transformer mostly is but device of forced oil-circulated air-cooled.The control cabinet of cooler is furnished with two independently power supplys, and one main one is equipped with, and when working power broke down, automatic put-in spair power source sent the power failure alarm signal to the control room simultaneously.Yet the electric component and the line configuring of two power supplys are improper, the potential faults that may exist stand-by power supply not drop into automatically, thus cause the cooler full cut-off, and this moment, the operator on duty can not discover, and until the circuit breaker trip of transformer, caused power supply to stop; Perhaps because the disturbance of upstream power supply causes the mistake of power supply to be switched.

The utility model content:

The utility model purpose provides the air-cooled control cabinet double-power supply switching device of large-scale power transformer, and safety, reliable guarantees the operation of transformer long-term safety, solves the problems referred to above that exist in the background technology.

The technical solution of the utility model is:

The air-cooled control cabinet double-power supply switching device of large-scale power transformer comprises power and monitoring circuit, ac control circuit, DC control circuit; Power and monitoring circuit comprise two power supplys, two groups of A.C. contactor main contacts, four phase sequence relays, bus connection switch, each power supply and two phase sequence relays, one group of A.C. contactor main contact are linked in sequence, and connect by bus connection switch between two power supplys; Ac control circuit comprises the control loop of controlling two power supplys respectively, and each control loop is formed by A.C. contactor, auxiliary relay, the time relay, Control Node; DC control circuit comprises change over switch, the moving disconnected auxiliary contact of transformer breaker, auxiliary relay, and change over switch, the moving disconnected auxiliary contact of transformer breaker, auxiliary relay are serially connected in same loop, control the break-make of cooler main power source automatically.

The beneficial effects of the utility model: adopt above-mentioned double-power supply switching device, when power supply is broken down, excision trouble power, automatic put-in spair power source.Can monitor fallible component in the circuit simultaneously.Avoid because the electric component fault causes power supply not switch, thereby cause transformer because the cooling system power failure tripping.Guarantee more reliably is provided for the stability of electric power system.Be specially adapted to the 1000kV transmitting transformer.

Description of drawings:

Fig. 1 is the utility model embodiment medium power and monitoring circuit appliance wiring figure;

Fig. 2 is ac control circuit appliance wiring figure among the utility model embodiment;

Fig. 3 is DC control circuit appliance wiring figure among the utility model embodiment.

Among the figure: power supply I, II; Auxiliary relay K1, K2, K6, K8, K9, K10, K11; Time relay KT1, KT2, KT7, KT8; A.C. contactor KMM1, KMM2; Phase sequence relay KX1, KX2, KX3, KX4; Electrical source of power automatic switch QF11, QF21; Bus connection switch QM; DC power supply control switch QM3; Change over switch SAM1; Transformer breaker moving disconnected auxiliary contact QF1, QF2, QF3.

Embodiment:

Below in conjunction with accompanying drawing, the utility model is described in further detail by embodiment.

In an embodiment, the air-cooled control cabinet double-power supply switching device of large-scale power transformer comprises power and monitoring circuit, ac control circuit, DC control circuit; Power and monitoring circuit comprise two three-phase four-wire powers, two groups of A.C. contactor contacts, four phase sequence relays, bus connection switch, each three-phase four-wire power and two phase sequence relays, one group of A.C. contactor contact are linked in sequence, and connect by bus connection switch between two three-phase four-wire powers; Ac control circuit comprises the control loop of controlling two three-phase electrical source of power respectively, and each control loop is formed by A.C. contactor, auxiliary relay, the time relay, Control Node; DC control circuit comprises change over switch, the moving disconnected auxiliary contact of transformer breaker, auxiliary relay, and change over switch, the moving disconnected auxiliary contact of transformer breaker, auxiliary relay are serially connected in same loop, control the operating state of Cooler Power automatically.

Power supply I, II are respectively equipped with electrical source of power automatic switch QF11, QF21, and DC control circuit is provided with DC power supply control switch QM3.

With reference to accompanying

drawing

1,2,3, the utility model course of work:

After transformer puts into operation, the auxiliary break contact of its circuit breaker Q F1, QF2, QF3 opens → and K6 coil blackout → K6 break contact returns (closure); When three four line power supply I are normal, change over switch SAM1 is in three four line power supply I service positions, KX1 make contact closure → K1 coil magnetization → K1 make contact closure; If KMM1 contactor fault-free → K10 coil is excitation → K10 break contact closure not; If satisfy above-mentioned three conditions, contactor KMM1 coil electricity then, its main contacts closure → cooler are connected three four line power supply I operations.

The first kind is switched: working power breaks down

1, when working power I three-phase imbalance or situation generation → KX1 make contact disconnection → K1 coil that phase shortage arranged excitation → K1 break contact closure not, K1 make contact disconnection → contactor KMM1 coil not excitation → KMM1 main contacts disconnection → trouble power I is cut.

2, when three four line power supply II normal, the moving moving auxiliary contact closure of closing of auxiliary contact closure → K2 coil magnetization → K2 of closing of KX2.

3, when KMM2 contactor fault-free → K11 coil excitation → K11 break contact closure not.

If satisfy above-mentioned three conditions, contactor KMM2 coil electricity then, its main contacts closure → cooler are connected three four line power supply II operations.

Second class is switched: the main contactor coil breaks down

1, when main contactor KMM1 coil break down → the KMM1 main contacts disconnects, power supply I quits work (trouble power is cut), the moving disconnected auxiliary contact closure of KMM1.

2, when power supply I normal → the moving moving auxiliary contact closure of closing of auxiliary contact closure → K1 coil magnetization → K1 make contact closure → time relay KT2 closure → K9 coil magnetization → K9 of closing of KX1.

3, when power supply II normal, KX2 make contact closure → K2 coil magnetization → K2 make contact closure.

4, when KMM2 contactor fault-free → K11 coil excitation → K11 break contact closure not.

If satisfy above-mentioned four conditions, contactor KMM2 coil electricity then, its main contacts closure → cooler energized II operation.

The 3rd class is switched: the main contactor main contacts breaks down

When main contactor KMM1 main contacts breaks down, its auxiliary contact are normal → and KX3 break contact closure → KT7 coil magnetization → K7 time-delay make contact closure → K10 coil magnetization → K10 break contact disconnects, K10 make contact closure → main contactor KMM1 coil not excitation → KMM1 main contacts disconnects, power supply I quit work (trouble power is cut).

2, when power supply I normal → KX1 make contact closure → K1 coil magnetization → K1 make contact closure, → time relay KT2 closure → K9 coil magnetization → K9 make contact closure.

3, when power supply II normal, the moving moving auxiliary contact closure of closing of auxiliary contact closure → K2 coil magnetization → K2 of closing of KX2.

4, when KMM2 contactor fault-free → K11 coil moving disconnected closure of lifting one's head of excitation → K11 not.

Power supply I and power supply II and bus power supply adopt KX1, KX2, KX3 phase sequence relay to monitor respectively simultaneously, this relay can not only be monitored whether phase shortage and three phase mains balance whether of three phase mains, can also adjust to the fluctuation range and the time of supply voltage according to actual conditions simultaneously; So not only can avoid power supply that mistake takes place and switch, make control circuit simple and reliable simultaneously.

Claims

1. the air-cooled control cabinet double-power supply switching device of large-scale power transformer is characterized in that comprising power and monitoring circuit, ac control circuit, DC control circuit; Power and monitoring circuit comprise two power supplys (I, II), two groups of A.C. contactor contacts (KMM1, KMM2), four phase sequence relays (KX1, KX2, KX3, KX4), bus connection switch (QM), each power supply and two phase sequence relays, one group of A.C. contactor contact are linked in sequence, and connect by bus connection switch between two power supplys; Ac control circuit comprises the control loop of controlling two power supplys respectively, and each control loop is formed by A.C. contactor, auxiliary relay, the time relay, Control Node; DC control circuit comprises change over switch (SAM1), the moving disconnected auxiliary contact (QF1, QF2, QF3) of transformer breaker, auxiliary relay, and change over switch, the moving disconnected auxiliary contact of transformer breaker, auxiliary relay are serially connected in same loop.