CN202513594U - Intelligent-controlled 35kV transformer parallel operation automatic switching device - Google Patents

Intelligent-controlled 35kV transformer parallel operation automatic switching device Download PDF

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Publication number
CN202513594U
CN202513594U CN2012201792466U CN201220179246U CN202513594U CN 202513594 U CN202513594 U CN 202513594U CN 2012201792466 U CN2012201792466 U CN 2012201792466U CN 201220179246 U CN201220179246 U CN 201220179246U CN 202513594 U CN202513594 U CN 202513594U
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China
Prior art keywords
circuit
transformer
relay
pressure side
separating brake
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Expired - Fee Related
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CN2012201792466U
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Chinese (zh)
Inventor
陈蕾
陈家斌
崔军朝
葛秦岭
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Zhumadian Power Supply Co of Henan Electric Power Co
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Zhumadian Power Supply Co of Henan Electric Power Co
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Priority to CN2012201792466U priority Critical patent/CN202513594U/en
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Publication of CN202513594U publication Critical patent/CN202513594U/en
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/70—Smart grids as climate change mitigation technology in the energy generation sector
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/12—Monitoring or controlling equipment for energy generation units, e.g. distributed energy generation [DER] or load-side generation

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Abstract

The utility model discloses an intelligent-controlled 35kV transformer parallel operation automatic switching device. The intelligent-controlled automatic 35kV transformer parallel operation automatic switching device comprises a current detecting and converting circuit, a current judging and processing circuit, a transformer input switching-on circuit and a transformer exit switching-off circuit, wherein the current detecting and converting circuit is connected in series to a high-voltage side of a first transformer; a signal output end of the current detecting and converting circuit is connected with a signal input end of the current judging and processing circuit; a signal output end of the current judging and processing circuit is connected with signal input ends of the transformer input switching-on circuit and the transformer exit switching-off circuit respectively; and signal output ends of the transformer input switching-on circuit and the transformer exit switching-off circuit are connected with an input switching-on breaker circuit and an exit switching-off breaker circuit of a second transformer respectively. The intelligent-controlled 35kV transformer parallel operation automatic switching device can reduce labor intensity and improve the running safety and reliability of transformers.

Description

Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device
Technical field
The utility model relates to the transformer switching device, relates in particular to the automatic switching device that is applied to the parallel running of electric power system 35kV transforming plant main transformer depressor.
Background technology
At present; The electric power system power load throughout the year or all had peak, low-valley interval in one day 24 hours; People are in order to reduce the no-load loss of electric power system low-valley interval power transformer; Generally be to adopt two and the operation of above transformers connected in parallel, power load transformer peak period full capacity puts into operation, and power load low-valley interval transformer stops an operation.And transformers connected in parallel operation throwing, retreating operation all need be operated according to the size of load by the operation operator on duty; Just load and go operation to drop into a transformer by the operator on duty big the time, the little time marquis that load goes to operate by the operator on duty and withdraws from a transformer.But the time of operating like this is longer, and operator on duty's labour intensity is big, and has unsafe misoperation factor.
The utility model content
The purpose of the utility model provides a kind of Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device, can reduce labour intensity, improve the security reliability of transformer operation.
The utility model adopts following technical proposals: a kind of Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device; Comprise that current detecting translation circuit, electric current judgment processing circuit, transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit; Described current detecting translation circuit is used for being connected on the high-pressure side of first transformer; The signal output part of current detecting translation circuit is connected with the signal input part of electric current judgment processing circuit; The signal output part of electric current judgment processing circuit connects the signal input part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit respectively, the input combined floodgate breaker circuit that the signal output part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit is connected second transformer respectively with withdraw from the separating brake breaker circuit.
Described transformer input combined floodgate circuit is connected with transformer station collection control center or transformer station's background computer through telecommunication circuit with the alarm signal output ends that transformer withdraws from the separating brake circuit.
Described current detecting translation circuit comprises current transformer, current transducer; The input of current transformer is connected on the high-pressure side of first transformer; The output of current transformer is connected with the input of current transducer, and the output of current transducer is connected with the input of electric current judgment processing circuit.
Described electric current judgment processing circuit comprises the A/D change-over circuit, calculates decision circuitry, delay circuit; Executive circuit; The output of A/D change-over circuit is connected with the input that calculates decision circuitry, and the output that calculates decision circuitry connects executive circuit through delay circuit.
Described executive circuit comprises that separating brake execution relay is withdrawed from high-pressure side input combined floodgate execution relay, low-pressure side input combined floodgate execution relay, high-pressure side, low-pressure side withdraws from separating brake execution relay.
Described transformer input combined floodgate circuit comprises high-pressure side input combined floodgate circuit and low-pressure side input combined floodgate circuit; The high-pressure side is dropped into the combined floodgate circuit and is comprised first relay; The normally opened contact of carrying out relay of the closing a floodgate back access power supply of connect is dropped in the coil of first relay and high-pressure side, and first normally opened contact of first relay is connected in the transformer high-voltage side input combined floodgate breaker circuit; Low-pressure side input combined floodgate circuit comprises second relay; Second normally opened contact of the coil of second relay and first relay, the low-pressure side input normally opened contact of the carrying out relay back access power supply of connect that closes a floodgate, the normally opened contact of second relay is connected in the step down side input combined floodgate breaker circuit.
Described transformer withdraws from the separating brake circuit and comprises that the separating brake circuit is withdrawed from the high-pressure side and low-pressure side withdraws from the separating brake circuit; Low-pressure side withdraws from the separating brake circuit and comprises the 3rd relay; The coil of the 3rd relay and high-pressure side are withdrawed from separating brake and are carried out the normally opened contact of the relay back access power supply of connect, and first normally opened contact of the 3rd relay is connected on the transformer high-voltage side and withdraws from the separating brake breaker circuit; The high-pressure side is withdrawed from the separating brake circuit and is comprised the 4th relay; The coil of the 4th relay and second normally opened contact, the low-pressure side of the 3rd relay withdraw from separating brake and carry out the normally opened contact of the relay back access power supply of connect, and the normally opened contact of the 4th relay is connected on step down side and withdraws from the separating brake breaker circuit.
The utlity model has the transformer load electric current is detected arbitration functions automatically, can promptly and accurately adjust the economical operation of distribution transformer, accomplish the economical parallel running throwing of 35kV main transformer automatically and move back work, reduce the running wastage of electrical network effectively; Deducted operations staff's complicated heavy grid switching operation, prior one is to have improved security reliability simultaneously, has reduced misoperation.This apparatus structure is simple, is skillfully constructed, science reasonable in design, and cost is low, and is easy to use.
Description of drawings
Fig. 1 is the schematic block circuit diagram of the utility model;
Fig. 2 is the current detecting translation circuit of the utility model and the connecting circuit figure of transformer;
Fig. 3 is the transformer high-voltage side input combined floodgate circuit diagram of the utility model;
Fig. 4 is the step down side input combined floodgate circuit diagram of the utility model;
Fig. 5 withdraws from the separating brake circuit diagram for the step down side of the utility model;
Fig. 6 withdraws from the separating brake circuit diagram for the transformer high-voltage side of the utility model.
Embodiment
Like Fig. 1, shown in Figure 2; A kind of Based Intelligent Control 35kV transformers connected in parallel operation of the utility model automatic switching device; Comprise that current detecting translation circuit, electric current judgment processing circuit, transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit; Described current detecting translation circuit comprises current transformer LH, current transducer KA; The input of current transformer LH is connected on the high-pressure side of first transformer T1, and the LH output of current transformer is connected with the input of current transducer KA, and the output of current transducer KA is connected with the input of electric current judgment processing circuit; Described electric current judgment processing circuit comprises the A/D change-over circuit, calculates decision circuitry, delay circuit; Executive circuit; The output of A/D change-over circuit is connected with the input that calculates decision circuitry; Calculating decision circuitry can realize with single-chip microcomputer, and the output that calculates decision circuitry connects executive circuit through delay circuit; The signal output part of executive circuit connects the signal input part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit respectively, the input combined floodgate breaker circuit that the signal output part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit is connected second transformer T2 respectively with withdraw from the separating brake breaker circuit.Described transformer input combined floodgate circuit is connected with transformer station collection control center or transformer station's background computer through fiber optic cables circuit or copper core cable circuit with the alarm signal output ends that transformer withdraws from the separating brake circuit.
Described executive circuit comprises that separating brake execution relay is withdrawed from high-pressure side input combined floodgate execution relay, low-pressure side input combined floodgate execution relay, high-pressure side, low-pressure side withdraws from separating brake execution relay.Described transformer input combined floodgate circuit comprises high-pressure side input combined floodgate circuit and low-pressure side input combined floodgate circuit (G1, G2 are respectively the action contact of high-pressure side circuit breaker, low-pressure side circuit breaker); As shown in Figure 3; The high-pressure side is dropped into the combined floodgate circuit and is comprised first relay; The normally opened contact K1 that carries out relay of the closing a floodgate back access power supply (A that connect is dropped in the coil KHG of first relay and high-pressure side; N), first normally opened contact of first relay is connected in the transformer high-voltage side input combined floodgate breaker circuit; As shown in Figure 4; Low-pressure side input combined floodgate circuit comprises second relay; The second normally opened contact KHG2 of the coil KHD of second relay and first relay, the low-pressure side input normally opened contact K2 that the carries out relay back access power supply of connect that closes a floodgate, the normally opened contact of second relay is connected in the step down side input combined floodgate breaker circuit.
Described transformer withdraws from the separating brake circuit and comprises that the separating brake circuit is withdrawed from the high-pressure side and low-pressure side withdraws from the separating brake circuit; As shown in Figure 5; Low-pressure side withdraws from the separating brake circuit and comprises the 3rd relay; The coil KFD and the high-pressure side of the 3rd relay withdrawed from separating brake and carried out the normally opened contact K3 of the relay back access power supply of connect, and first normally opened contact of the 3rd relay is connected on the transformer high-voltage side and withdraws from the separating brake breaker circuit; As shown in Figure 6; The high-pressure side is withdrawed from the separating brake circuit and is comprised the 4th relay; The coil KFG of the 4th relay and the second normally opened contact KFD2, the low-pressure side of the 3rd relay withdraw from separating brake and carry out the normally opened contact K4 of the relay back access power supply of connect, and the normally opened contact of the 4th relay is connected on step down side and withdraws from the separating brake breaker circuit.
Like Fig. 1, shown in Figure 2; The on high-tension side current signal that detects the first transformer T1 by the current detecting translation circuit inputs to electric current judgment processing circuit to carry out current signal and calculates judgment processing; Judge two kinds of sizes values according to input current signal; Through passing the signal to transformer input combined floodgate circuit or withdraw from the separating brake circuit after the time-delay; Accomplish automatic switching transformer task, transformer sends alarm signal to transformer station collection control center or transformer station's background computer through fiber optic cables circuit or copper core cable circuit after withdrawing from separating brake or transformer input combined floodgate, sends alarm signal at said transformer station collection control center or transformer station's background computer; Demonstrate on the screen that device puts into operation or signal out of service, and show it is that certain transformer station, certain main transformer put into operation or out of service.
When electric current judgment processing circuit judges reached the big current value of setting, the time-delay back started high-pressure side input combined floodgate and carries out the actuating of relay, and its normally open contact K1 is closed; The combined floodgate circuit is dropped in the starting transformer high-pressure side, and first normally opened contact of first relay and the second normally opened contact KHG2 are closed, and the combined floodgate circuit breaker is dropped in the starting transformer high-pressure side; And then delayed startup low-pressure side input combined floodgate is carried out the actuating of relay; Its normally open contact K2 is closed, starting transformer low-pressure side input combined floodgate circuit, and the normally opened contact of second relay is closed; Starting transformer low-pressure side input combined floodgate circuit breaker is accomplished the transformer work that puts into operation.The operation sequence that drops into the 35KV transformer is: close transformer high-voltage side circuit breaker earlier, close the low-pressure side circuit breaker again; The high-pressure side circuit breaker of transformer closes not brake application; The low-pressure side circuit breaker can not close a floodgate, and there is mutual blocking function in high pressure, low-pressure side breaker closing loop.
When electric current judgment processing circuit judges reached the little current value of setting, the time-delay back started low-pressure side and withdraws from the separating brake execution actuating of relay, and its normally open contact K3 is closed; The starting transformer low-pressure side withdraws from the separating brake circuit, and first normally opened contact of the 3rd relay and the second normally opened contact KFD2 are closed, and the starting transformer low-pressure side withdraws from the separating brake circuit breaker; And then the separating brake execution actuating of relay is withdrawed from the delayed startup high-pressure side; Its normally open contact K4 is closed, and the separating brake circuit is withdrawed from the starting transformer high-pressure side, and the normally opened contact of the 4th relay is closed; The separating brake circuit breaker is withdrawed from the starting transformer high-pressure side, accomplishes transformer work out of service.Withdrawing from 35KV transformer power failure operation sequence is: break off earlier the step down side circuit breaker, break off the high-pressure side circuit breaker again, the low-pressure side circuit breaker of transformer is non-shut-brake, and the high-pressure side circuit breaker can not separating brake, and high pressure, low-pressure side sub-gate circuit have mutual blocking function.
Explanation is at last: above case is only in order to the technical scheme of explanation the utility model, but not to its restriction; Although the utility model has been carried out detailed introduction with reference to preferred embodiment; The those of ordinary skill in affiliated field is to be understood that; Still can make amendment and perhaps the part technical characterictic replaced on an equal basis the embodiment of the utility model; And not breaking away from the spirit of the utility model technical scheme, it all should be encompassed in the middle of the scope of the technical scheme that the utility model asks for protection.

Claims (7)

1. a Based Intelligent Control 35kV transformers connected in parallel moves automatic switching device; It is characterized in that: comprise that current detecting translation circuit, electric current judgment processing circuit, transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit; Described current detecting translation circuit is used for being connected on the high-pressure side of first transformer; The signal output part of current detecting translation circuit is connected with the signal input part of electric current judgment processing circuit; The signal output part of electric current judgment processing circuit connects the signal input part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit respectively, the input combined floodgate breaker circuit that the signal output part that transformer input combined floodgate circuit and transformer withdraw from the separating brake circuit is connected second transformer respectively with withdraw from the separating brake breaker circuit.
2. Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device according to claim 1 is characterized in that: described transformer input combined floodgate circuit is connected with transformer station collection control center or transformer station's background computer through telecommunication circuit with the alarm signal output ends that transformer withdraws from the separating brake circuit.
3. Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device according to claim 1 and 2; It is characterized in that: described current detecting translation circuit comprises current transformer, current transducer; The input of current transformer is connected on the high-pressure side of first transformer; The output of current transformer is connected with the input of current transducer, and the output of current transducer is connected with the input of electric current judgment processing circuit.
4. Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device according to claim 3; It is characterized in that: described electric current judgment processing circuit comprises the A/D change-over circuit, calculates decision circuitry, delay circuit; Executive circuit; The output of A/D change-over circuit is connected with the input that calculates decision circuitry, and the output that calculates decision circuitry connects executive circuit through delay circuit.
5. Based Intelligent Control 35kV transformers connected in parallel according to claim 4 moves automatic switching device, it is characterized in that: described executive circuit comprises that separating brake execution relay is withdrawed from high-pressure side input combined floodgate execution relay, low-pressure side input combined floodgate execution relay, high-pressure side, low-pressure side withdraws from separating brake execution relay.
6. Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device according to claim 5; It is characterized in that: described transformer input combined floodgate circuit comprises high-pressure side input combined floodgate circuit and low-pressure side input combined floodgate circuit; The high-pressure side is dropped into the combined floodgate circuit and is comprised first relay; The normally opened contact of carrying out relay of the closing a floodgate back access power supply of connect is dropped in the coil of first relay and high-pressure side, and first normally opened contact of first relay is connected in the transformer high-voltage side input combined floodgate circuit breaker; Low-pressure side input combined floodgate circuit comprises second relay; Second normally opened contact of the coil of second relay and first relay, the low-pressure side input normally opened contact of the carrying out relay back access power supply of connect that closes a floodgate, the normally opened contact of second relay is connected in the step down side input combined floodgate circuit breaker.
7. Based Intelligent Control 35kV transformers connected in parallel operation automatic switching device according to claim 5; It is characterized in that: described transformer withdraws from the separating brake circuit and comprises that the separating brake circuit is withdrawed from the high-pressure side and low-pressure side withdraws from the separating brake circuit; Low-pressure side withdraws from the separating brake circuit and comprises the 3rd relay; The coil of the 3rd relay and high-pressure side are withdrawed from separating brake and are carried out the normally opened contact of the relay back access power supply of connect, and first normally opened contact of the 3rd relay is connected on the transformer high-voltage side and withdraws from the separating brake circuit breaker; The high-pressure side is withdrawed from the separating brake circuit and is comprised the 4th relay; The coil of the 4th relay and second normally opened contact, the low-pressure side of the 3rd relay withdraw from separating brake and carry out the normally opened contact of the relay back access power supply of connect, and the normally opened contact of the 4th relay is connected on step down side and withdraws from the separating brake circuit breaker.
CN2012201792466U 2012-04-25 2012-04-25 Intelligent-controlled 35kV transformer parallel operation automatic switching device Expired - Fee Related CN202513594U (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102611114A (en) * 2012-04-25 2012-07-25 河南省电力公司驻马店供电公司 Automatic switching device for intelligently controlling parallel operation of 35kV transformers
CN105869935A (en) * 2016-06-22 2016-08-17 国网四川省电力公司成都供电公司 Automatic overcurrent-blocking and on-load voltage regulation switching method and automatic overcurrent-blocking and on-load voltage regulation switching device of transformer

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102611114A (en) * 2012-04-25 2012-07-25 河南省电力公司驻马店供电公司 Automatic switching device for intelligently controlling parallel operation of 35kV transformers
CN105869935A (en) * 2016-06-22 2016-08-17 国网四川省电力公司成都供电公司 Automatic overcurrent-blocking and on-load voltage regulation switching method and automatic overcurrent-blocking and on-load voltage regulation switching device of transformer
CN105869935B (en) * 2016-06-22 2017-11-10 国网四川省电力公司成都供电公司 A kind of transformer overcurrent locking on-load voltage regulation automatic switching method and device

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GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20121031

Termination date: 20150425

EXPY Termination of patent right or utility model