CN107046292A - A kind of phase-change switch formula three-phase load unbalance controlling device - Google Patents

A kind of phase-change switch formula three-phase load unbalance controlling device Download PDF

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Publication number
CN107046292A
CN107046292A CN201710283272.0A CN201710283272A CN107046292A CN 107046292 A CN107046292 A CN 107046292A CN 201710283272 A CN201710283272 A CN 201710283272A CN 107046292 A CN107046292 A CN 107046292A
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CN
China
Prior art keywords
phase
change switch
magnetic latching
master controller
latching relay
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201710283272.0A
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Chinese (zh)
Inventor
郭跃武
冯智勇
杨俊义
常敬
冯波
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Tianjin Ziguang Qizhi Electric Technology Co Ltd
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Tianjin Ziguang Qizhi Electric Technology Co Ltd
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Priority to CN201710283272.0A priority Critical patent/CN107046292A/en
Publication of CN107046292A publication Critical patent/CN107046292A/en
Pending legal-status Critical Current

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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/26Arrangements for eliminating or reducing asymmetry in polyphase networks
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/50Arrangements for eliminating or reducing asymmetry in polyphase networks

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Remote Monitoring And Control Of Power-Distribution Networks (AREA)

Abstract

The invention discloses a kind of phase-change switch formula three-phase load unbalance controlling device, it is characterised in that:At least include:Control unit and executing agency;Executing agency includes at least one phase-change switch;Control unit includes at least one master controller;The current sensor of current information on detection branches power network;The signal output terminal of current sensor is electrically connected with the input terminal of master controller;Master controller is connected to three phase network;Each master controller can be connected by wire communication or radio communication with least one phase-change switch, and phase-change switch is electrically connected with load;Each master controller detection three phase unbalance current, the fault message of the phase-change switch of main controller controls, current phase, present load current;And by uneven calculative strategy, calculating obtains each switch-mode regulation target phase, issues commutation order.The patent can avoid larger the shoving in the generation of load switching moment, it is to avoid the loss of IGCT longtime running, and the carry out commutation that do not have a power failure.

Description

A kind of phase-change switch formula three-phase load unbalance controlling device
Technical field
The present invention relates to intelligent power distribution technical field, more particularly to a kind of phase-change switch formula three-phase load unbalance is administered Device.
Background technology
In recent years, China's distribution network construction input is continued to increase, and power distribution network development obtains remarkable effect, but electricity consumption level phase Still there is gap to international most advanced level, urban and rural areas disparate development, power supply quality is to be improved.Build urban-rural, safety Reliably, economical and efficient, advanced technology, environment-friendly distribution network facility and service system are achieved many things at one stroke, and can either ensure the people Raw, pulling investment, can drive related Manufacturing level to be lifted again, to promote " internet+" wisdom energy strategy to provide effectively Support, for steady growth, rush reform, adjusts structure, Huimin life significant.
Power distribution network is in the end of power system, and transmission range is long, and decompression level is more, and multi-point and wide-ranging, running status is transported The influence of line mode and load variations is larger, and these situations cause power distribution network to be in non-economy operation shape in certain area and period State to voltage and the index such as idle, it is necessary to carry out coordination control.Powered in the city dweller of low voltage three-phase four-wire system and rural power grids and be In system:Because electricity consumer is generally single-phase load or single-phase mixed with three-phase load, and payload is different and the electricity consumption time It is different.So, three alternate out-of-balance currents are objective reality in power network, and this electricity consumption unbalance condition is irregular Property, it can not also predict in advance.It result in the secular disequilibrium of low-voltage power supply system threephase load.
For three-phase load unbalance, solution main at present is directed to single-phase load when having early stage distribution network construction It is evenly distributed on three-phase load, balancing the load situation is checked in actual motion, then is manually adjusted, but this side Formula is uneconomical, and influences power supply continuity.
At present, three-phase load unbalance abatement equipment each side surface technology also prematurity, abroad in low power distribution network, Less use three-phase load unbalance abatement equipment.The general electric capacity using manually or automatically switching in part three-phase imbalance area Device group is compensated.But, even state-of-the-art IGCT split-phase switching capacitance group, the compensation that can only solve power factor is asked Topic, can not effectively balance three-phase load.
A kind of new power electronics formula three-phase imbalance controlling device is occurred in that in recent years, and it is with IGBT (insulated gate bipolars Transistor) switch for core reactive power compensation unit, using advanced PWM pulse modulation technologies, realize transformation of electrical energy A kind of totally digitilized power electronic equipment.Three-phase four-wire system typically is used, can fast and effectively be moved for fluctuating load State reactive-load compensation, is compensated to voltage fluctuation and flicker, load unbalanced, power factor, harmonic wave, is being effectively improved electric energy matter Amount.But there is the drawbacks such as high own loss, noise and harmonic pollution in it.
The phase-change switch formula three-phase load unbalance controlling device of current main flow is mainly using the scheme shown in Fig. 1.
This programme has three contactors altogether, three bidirectional thyristors, and be often in series fastp-acting fuse.Bidirectional thyristor is in parallel Contactor, make use of combination switch principle, and without arc no-voltage when can cause contactor switching, the commutation time is fast.But the program Bidirectional thyristor works in the line for a long time in force, if lightning impulse or other interference into device are likely to result in crystalline substance Brake tube misleads, and there is a possibility that phase fault.And contactor coil needs long-term powered closure, power consumption is big, aging is fast. And circuit power down is once controlled, contactor disconnects, and influences power supply continuity.
The content of the invention
The technical problem to be solved in the present invention is:A kind of phase-change switch formula three-phase load unbalance controlling device is provided.Should Phase-change switch formula three-phase load unbalance controlling device can avoid larger the shoving in the generation of load switching moment, avoid brilliant lock The loss of pipe longtime running, and the carry out commutation that do not have a power failure.
The present invention is adopted the technical scheme that to solve technical problem present in known technology:
A kind of phase-change switch formula three-phase load unbalance controlling device, it is characterised in that:At least include:
Control unit and executing agency;Wherein:
The executing agency includes at least one phase-change switch;
The control unit includes at least one master controller;
The current sensor of current information on detection branches power network;The signal output terminal of the current sensor with The input terminal electrical connection of master controller;
The master controller is connected to three phase network;Each master controller can by wire communication or radio communication with least One phase-change switch connection, phase-change switch is electrically connected with load;
Each master controller detection three phase unbalance current, the fault message of the phase-change switch of the main controller controls, when Preceding phase, present load current;By arranging the different commutation combinations of phase-change switch, optimal commutation scheme is obtained, is issued Commutation order.
Further:Each commutation include the magnetic that the double magnetic latching relays held of two hilted broadswords and a hilted broadsword list hold keep after Electrical equipment;The double magnetic latching relays held of described two hilted broadswords are the first magnetic latching relay, the second magnetic latching relay;Described one The magnetic latching relay that individual hilted broadsword list is held is the 3rd magnetic latching relay;The A of branch's power network connects line terminals and B phase connections Terminal is electrically connected with two input terminals of the first magnetic latching relay respectively;The lead-out terminal of first magnetic latching relay Electrically connected respectively with two input terminals of the second magnetic latching relay with the C of the branch power network line terminals that connect;Second magnetic The lead-out terminal of guard relay passes sequentially through the analog input end of the 3rd magnetic latching relay, current sensor and controller Son electrical connection;The two ends of 3rd magnetic latching relay are parallel with IGCT.
Further:Pass through GPRS mobile communication, power line carrier, PLC, channel radio between the controller and reversing switch Letter, one kind in wired 485 communication.
The present invention has the advantages and positive effects of:
By using above-mentioned technical proposal, this patent has the following advantages compared with conventional art:
1. operating power consumption is low, wastage reducing and energy saving;
2. current over-zero is cut off, voltage zero-cross input, rate of phase change is fast, no impact, long lifespan;
3. reliable hardware interlock, it is to avoid phase fault;
4. power-off does not influence power supply reliability;
5. modularized design, compact conformation, flexibly.
Brief description of the drawings:
Fig. 1 is the circuit diagram of conventional apparatus;
Fig. 2 is the circuit diagram of the preferred embodiment of the present invention;
Fig. 3 is the use state figure of the preferred embodiment of the present invention;
Embodiment
In order to further understand the content, features and effects of the present invention, hereby enumerating following examples, and coordinate accompanying drawing Describe in detail as follows:
Fig. 2 is referred to Fig. 3, a kind of phase-change switch formula three-phase load unbalance controlling device, including:
Control unit and executing agency;Wherein:
The executing agency includes at least one phase-change switch;
The control unit includes at least one master controller;
The current sensor of current information on detection branches power network;The signal output terminal of the current sensor with The input terminal electrical connection of controller;
The current sensor of current information on detection branches power network;The signal output terminal of the current sensor with The input terminal electrical connection of master controller;
Each master controller detection three phase unbalance current, the fault message of the phase-change switch of the main controller controls, when Preceding phase, present load current;And by uneven calculative strategy, calculating obtains each switch-mode regulation target phase, issues and change Phase command.
On the basis of above preferred embodiment:Each phase-change switch include the double magnetic latching relays held of two hilted broadswords and The magnetic latching relay that one hilted broadsword list is held;The double magnetic latching relays held of described two hilted broadswords are the first magnetic latching relay, Second magnetic latching relay;The magnetic latching relay that one hilted broadsword list is held is the 3rd magnetic latching relay;Branch's electricity The A of net connects line terminals and B connects, and line terminals are electrically connected with two input terminals of the first magnetic latching relay respectively;Described The lead-out terminal of one magnetic latching relay and the C of branch's power network line terminals that connect are defeated with two of the second magnetic latching relay respectively Enter terminal electrical connection;The lead-out terminal of second magnetic latching relay passes sequentially through the 3rd magnetic latching relay, current sense Device is electrically connected with the analog input terminal of controller;The two ends of 3rd magnetic latching relay are parallel with IGCT.
On the basis of above preferred embodiment:Pass through GPRS mobile communication, electricity between the controller and phase-change switch Power carrier communication, radio communication, one kind in wired 485 communication.
Above preferred embodiment is mainly made up of master controller with phase-change switch.Master controller is the control core of whole device The heart, phase-change switch is the executing agency of device, carries out information exchange by communicating between them, cooperates and completes to distribution three The improvement of phase imbalance problem.
Master controller is the control terminal of whole device, per covering device only one of which master controller.Master controller detection three The fault message of phase out-of-balance current and each phase-change switch, current phase, present load current, plan is calculated by imbalance Slightly, calculating obtains each switch-mode regulation target phase, issues commutation order.
Phase-change switch is the branch and executing agency of device, can spirit according to the capacity of branch road and the distribution situation difference of load The capacity and quantity of selection phase-change switch living.It is responsible for gathering load current data, by logical together with the status information of itself News are uploaded to master controller;The commutation order for receiving master controller carries out commutation operation;Receive the error protection life of master controller Order is operated accordingly;Show the running state information of itself.
Communicate compatible communication, including but not limited to GPRS mobile communication, electricity between master controller and phase-change switch Power carrier communication, radio communication, limited 485 communication.
This patent proposes following new scheme using the double magnetic latching relays held of two hilted broadswords, and a hilted broadsword list is held Magnetic latching relay, the program is except that can accomplish " current over-zero is cut off, voltage zero-cross input " outside during commutation, and three-phase switches Mutual locking, is not in phase fault, and volume of switch is all smaller than other schemes, beneficial to the Miniaturization Design of switch.
Phase-change switch can be carried out to modularized design, three-phase goes out single-phase one module of use, and three-phase, which goes out three-phase, to be used Three wired in parallel.
Embodiments of the invention are described in detail above, but the content is only presently preferred embodiments of the present invention, It is not to be regarded as the practical range for limiting the present invention.Any changes and modifications in accordance with the scope of the present application, Within the patent covering scope that the present invention all should still be belonged to.

Claims (3)

1. a kind of phase-change switch formula three-phase load unbalance controlling device, it is characterised in that:At least include:
Control unit and executing agency;Wherein:
The executing agency includes at least one phase-change switch;
The control unit includes at least one master controller;
The current sensor of current information on detection branches power network;The signal output terminal of the current sensor and master control The input terminal electrical connection of device processed;
The master controller is connected between mains network and branch's power network;Each master controller passes through wire communication or channel radio Letter is connected with least one phase-change switch, and phase-change switch is electrically connected with load;
Each master controller detection three phase unbalance current, the fault message of the phase-change switch of the main controller controls, current phase Position, present load current;By arranging the different commutation combinations of phase-change switch, optimal commutation scheme is obtained, commutation is issued Order.
2. phase-change switch formula three-phase load unbalance controlling device according to claim 1, it is characterised in that:Each commutation is opened Closing includes the magnetic latching relay that the double magnetic latching relays held of two hilted broadswords and a hilted broadsword list are held;Described two hilted broadswords are double to be held Magnetic latching relay be the first magnetic latching relay, the second magnetic latching relay;Magnetic that one hilted broadsword list is held keep after Electrical equipment is the 3rd magnetic latching relay;The A of branch's power network connects line terminals and B connects, and line terminals are kept with the first magnetic respectively Two input terminals electrical connection of relay;The lead-out terminal of first magnetic latching relay and the C phase connections of branch's power network Terminal is electrically connected with two input terminals of the second magnetic latching relay respectively;The lead-out terminal of second magnetic latching relay The 3rd magnetic latching relay, current sensor is passed sequentially through to electrically connect with the analog input terminal of master controller;Described 3rd The two ends of magnetic latching relay are parallel with IGCT.
3. phase-change switch formula three-phase load unbalance controlling device according to claim 1, it is characterised in that:The controller By GPRS mobile communication, power line carrier, PLC, radio communication between phase-change switch, one kind in wired 485 communication.
CN201710283272.0A 2017-04-26 2017-04-26 A kind of phase-change switch formula three-phase load unbalance controlling device Pending CN107046292A (en)

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CN201710283272.0A CN107046292A (en) 2017-04-26 2017-04-26 A kind of phase-change switch formula three-phase load unbalance controlling device

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Application Number Priority Date Filing Date Title
CN201710283272.0A CN107046292A (en) 2017-04-26 2017-04-26 A kind of phase-change switch formula three-phase load unbalance controlling device

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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107634527A (en) * 2017-11-09 2018-01-26 中气电力装备有限公司 A kind of regulating system for administering distribute-electricity transformer district three-phase imbalance
CN108063446A (en) * 2017-12-20 2018-05-22 厦门宏发电力电器有限公司 A kind of three-phase phase reversal relay combining structure
CN108206530A (en) * 2018-03-02 2018-06-26 国网江苏省电力有限公司宜兴市供电分公司 A kind of load control method, apparatus and system with no-power compensation function
CN108281975A (en) * 2018-03-20 2018-07-13 辰昊电力设备(深圳)有限公司 A kind of distributed intelligence three-phrase burden balance phase-change switch
CN108390400A (en) * 2018-05-07 2018-08-10 北京波粒智电科技有限公司 Prevent the three-phase circuit phase-selecting switch system and method for relay failure short circuit
CN108429273A (en) * 2018-03-30 2018-08-21 杭州海兴电力科技股份有限公司 Three-phase balanced system suitable for power grid
CN108427071A (en) * 2018-05-15 2018-08-21 国网福建省电力有限公司电力科学研究院 A kind of phase-change switch intelligent detection device and method
CN108512236A (en) * 2018-05-18 2018-09-07 河南森源电气股份有限公司 A kind of phase-change switch and three-phase filter
CN108539770A (en) * 2018-05-14 2018-09-14 浙江星明智能电气科技有限公司 Phase-change switch type three-phase load unbalance administers regulating device and its application method
CN108565876A (en) * 2018-05-29 2018-09-21 吉林特纳普节能技术有限公司 A kind of no power-off has load commutation circuit
CN108599205A (en) * 2018-06-28 2018-09-28 浙江百固电气科技股份有限公司 A kind of phase-change switch main circuit and control method
CN108736495A (en) * 2018-07-03 2018-11-02 北京智创骏驰电气科技有限公司 A kind of novel phase-change switch device
CN108957067A (en) * 2018-01-10 2018-12-07 厦门宏发电力电器有限公司 A kind of three phase network keeps balance unit/terminal converter and its ammeter
CN108988363A (en) * 2018-07-11 2018-12-11 浙江百固电气科技股份有限公司 A kind of phase-change switch device and the scheduling application system using the above phase-change switch device
CN109347126A (en) * 2018-10-25 2019-02-15 山东电工电气集团新能科技有限公司 A kind of intelligent, phase changing type three-phase current unbalance self-checking device
CN110531146A (en) * 2019-09-02 2019-12-03 北京智芯微电子科技有限公司 Zero crossing detection device, method and the computer storage medium of Three Phase Carrier Based communication module
CN111044893A (en) * 2019-12-12 2020-04-21 云南电网有限责任公司临沧供电局 System and method for measuring load response time of phase change switch

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106169758A (en) * 2016-08-01 2016-11-30 北京燕能电气技术有限公司 A kind of device and method of automatic raising low voltage three-phase line end voltage

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106169758A (en) * 2016-08-01 2016-11-30 北京燕能电气技术有限公司 A kind of device and method of automatic raising low voltage three-phase line end voltage

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107634527B (en) * 2017-11-09 2024-03-19 中气电力装备有限公司 Regulation system for treating three-phase imbalance of distribution transformer area
CN107634527A (en) * 2017-11-09 2018-01-26 中气电力装备有限公司 A kind of regulating system for administering distribute-electricity transformer district three-phase imbalance
CN108063446B (en) * 2017-12-20 2024-05-14 厦门宏发电力电器有限公司 Three-phase change relay combination structure
CN108063446A (en) * 2017-12-20 2018-05-22 厦门宏发电力电器有限公司 A kind of three-phase phase reversal relay combining structure
CN108957067A (en) * 2018-01-10 2018-12-07 厦门宏发电力电器有限公司 A kind of three phase network keeps balance unit/terminal converter and its ammeter
CN108206530A (en) * 2018-03-02 2018-06-26 国网江苏省电力有限公司宜兴市供电分公司 A kind of load control method, apparatus and system with no-power compensation function
CN108281975A (en) * 2018-03-20 2018-07-13 辰昊电力设备(深圳)有限公司 A kind of distributed intelligence three-phrase burden balance phase-change switch
CN108429273A (en) * 2018-03-30 2018-08-21 杭州海兴电力科技股份有限公司 Three-phase balanced system suitable for power grid
CN108390400A (en) * 2018-05-07 2018-08-10 北京波粒智电科技有限公司 Prevent the three-phase circuit phase-selecting switch system and method for relay failure short circuit
CN108390400B (en) * 2018-05-07 2023-11-21 北京波粒智电科技有限公司 Three-phase circuit phase selection switch system and method for preventing relay from failure short circuit
CN108539770A (en) * 2018-05-14 2018-09-14 浙江星明智能电气科技有限公司 Phase-change switch type three-phase load unbalance administers regulating device and its application method
CN108427071A (en) * 2018-05-15 2018-08-21 国网福建省电力有限公司电力科学研究院 A kind of phase-change switch intelligent detection device and method
CN108427071B (en) * 2018-05-15 2024-01-23 国网福建省电力有限公司电力科学研究院 Intelligent detection device and method for phase change switch
CN108512236A (en) * 2018-05-18 2018-09-07 河南森源电气股份有限公司 A kind of phase-change switch and three-phase filter
CN108565876A (en) * 2018-05-29 2018-09-21 吉林特纳普节能技术有限公司 A kind of no power-off has load commutation circuit
CN108599205A (en) * 2018-06-28 2018-09-28 浙江百固电气科技股份有限公司 A kind of phase-change switch main circuit and control method
CN108736495A (en) * 2018-07-03 2018-11-02 北京智创骏驰电气科技有限公司 A kind of novel phase-change switch device
CN108988363A (en) * 2018-07-11 2018-12-11 浙江百固电气科技股份有限公司 A kind of phase-change switch device and the scheduling application system using the above phase-change switch device
CN109347126A (en) * 2018-10-25 2019-02-15 山东电工电气集团新能科技有限公司 A kind of intelligent, phase changing type three-phase current unbalance self-checking device
CN110531146B (en) * 2019-09-02 2020-11-03 北京智芯微电子科技有限公司 Zero-crossing detection device and method for three-phase carrier communication module and computer storage medium
CN110531146A (en) * 2019-09-02 2019-12-03 北京智芯微电子科技有限公司 Zero crossing detection device, method and the computer storage medium of Three Phase Carrier Based communication module
CN111044893A (en) * 2019-12-12 2020-04-21 云南电网有限责任公司临沧供电局 System and method for measuring load response time of phase change switch
CN111044893B (en) * 2019-12-12 2020-11-13 云南电网有限责任公司临沧供电局 System and method for measuring load response time of phase change switch

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Application publication date: 20170815