CN203933483U - Have the novel electric power transformer control system of D.C. magnetic biasing and no-power compensation function concurrently - Google Patents
Have the novel electric power transformer control system of D.C. magnetic biasing and no-power compensation function concurrently Download PDFInfo
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- CN203933483U CN203933483U CN201420334283.9U CN201420334283U CN203933483U CN 203933483 U CN203933483 U CN 203933483U CN 201420334283 U CN201420334283 U CN 201420334283U CN 203933483 U CN203933483 U CN 203933483U
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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
- Y02E40/30—Reactive power compensation
Abstract
The utility model relates to a kind of novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently, comprise the equiva lent impedance, PWM controlled rectifier, single-phase inverter, electric capacity, the forward that are connected with electrical network magnetize control contactor, oppositely magnetize control contactor, demagnetization control contactor and CPU, PWM controlled rectifier, single-phase inverter, forward magnetize control contactor, oppositely magnetize control contactor, demagnetization control contactor is all connected with CPU.The utility model has utilized the function of the conversion to two-phase magnetic material magnetic characteristic, makes transformer self have the ability that suppresses D.C. magnetic biasing and idle adjusting.Reduce electric power system loss, energy-saving effect is obvious; And overcome the deficiency that traditional inhibition D.C. magnetic biasing method is brought, ensured the reliable ground of transformer neutral point; The reliability that has improved power network and transformer safe operation, has great practical significance to whole electric power system.
Description
Technical field
The utility model relates to field of power electronics, relate to a kind of novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently, this device also can be used to control the conversion of two-phase magnetic material magnetic characteristic and realizes the ability with transformer DC magnetic bias compensation and reactive power compensation simultaneously.
Background technology
Since twentieth century the seventies and eighties, along with the development of superhigh pressure remote conveying electric system and the aggravation of power system load variable effect, reactive power consumption in electrical network increases day by day, and reactive power deficiency is to cause the key factor that China's quality of power supply is not high and waste.Controlled reactor and capacitor group are also moved mutual coordination and can be regulated idle.So at ultra high voltage or superhigh pressure, in jumbo electrical network, certain reactive power compensator is installed and is controlled reactive power flow, stablize the working voltage of electrical network.A large amount of theoretical research and facts have proved, regulate reactance to have significant effect for the runnability that improves electric power system, application that particularly can reactor, its capacity can change automatically along with the size of through-put power, too high power frequency switching overvoltage and corresponding transient state concussion overvoltage that circuit one side switch produces while suiting are prevented, also can reduce grid loss, improve the quality of power supply, brought huge economic benefit and social benefit simultaneously.So the research of controlled reactor more and more becomes countries nowadays Power decision and Electric Design personnel's common objective.
Nineteen sixty-five, General Electric Co. Limited of Britain manufactured First controlled reactor in the world, 1977 ~ 1978 years, GE company of the U.S., Westinghouse Electric and BBC company successively develop the static compensation device, superhigh pressure TCT type static compensation device, the thyristor-controlled reactor (TCR) that adopt thyristor control.1986, the former Soviet Union proposed novel controlled reactor structure, thereby makes saturated controllable reactor have breakthrough, and reactor performance has had greatly to be improved.The researcher of Japan has proposed the controlled reactor based on controlling magnetic flux principle orthocore subsequently; More American-European countries also start controlled reactor to study.In the last few years, the research to controllable electrical appliance of Chinese scholars and scientific research institution, all obtain in many aspects achievement, as controlled reactor, the transformer type controlled reactor based on controllable load principle, orthocore formula controlled reactor, the ultra-high/extra-high voltage controlled reactor etc. based on flux-gate principle controlled based on PWM.
Domestic the research of controlled reactor is mainly concentrated in direct-current controllable reactor and Controllable Reactor.Aspect direct-current controllable reactor, Wuhan University, Shanghai Communications University and North China Electric Power University conduct in-depth research.Aspect AC reactor, Zhejiang University, the Central China University of Science and Technology have launched the research of this aspect.The former Wuhan Water Conservancy and Electric Power Univ of China started novel controlled reactor to study in nineteen ninety, and had obtained a series of achievement in research.Within 1977, succeed in developing the automatic tuning arc depression coil based on magnetic valve type controllable reactor, within 1988, develop the controlled reactor of 27.5KV electric railroad dynamic passive compensation, be just devoted to more theory and the application study of voltage levels, more jumbo controlled reactor at present.The research of ultra high voltage controlled reactor is also had to the institution of higher learning such as Hunan University, Xi'an Communications University, Zhejiang University, the Central China University of Science and Technology, and the business unit such as Hengyang Transformer Co., Ltd., Tebian Electric Co., special power transformation work Shenyang transformer Co., Ltd and Xi'an transformer Co., Ltd.
Along with the electric power development general policy of China's " transferring electricity from the west to the east; north and south supplies mutually; national network ", HVDC Transmission Technology will become the interconnected main solution route of nationwide integrated power grid, and therefore DC transmission system stable operation has important function for the safety and stability of whole electrical network.But along with large capacity, the long application apart from direct current transportation, the grounding electrode electric current of the DC transmission system of moving with the earth echo plex mode can flow through Transformer Winding by transformer neutral point, causes transformer DC magnetic bias phenomenon.The direct current that transformer neutral point is introduced is in the inner D.C. magnetic biasing that forms of transformer, can make magnetic flux unshakable in one's determination seriously saturated, exciting current high distortion, produce a large amount of harmonic waves, noise obviously increases, and hardware loss increases, reactive loss increases, when serious, may cause local overheating phenomenon, destroy insulation, so that damage transformer or reduce the life-span.
On March 13rd, 1989; DC magnetic bias phenomena causes Quebec, CAN hydroelectric power generation interruption; the large-sized booster transformer in power station, east coast of the united states is ruined; the copper connector lug that wherein connects two low pressure winding conducting wires burns; the protective relaying maloperation of electrical network SVC device is done, and a large amount of capacitors are out of service, system voltage collapse; finally lose 9500MW load, grid disconnection nearly 9 hours.
1992; US Experts is taking hydroelectric station, Quebec Radisson/LG2 association as object; the scheme of several inhibition direct currents has been proposed; its method is by the neutral line less capacitor of power frequency impedance of connecting; with gap, can triggered gap and MOV etc. realize the quick overvoltage protection of neutral point capacitor, scheme is also equipped with mechanical by-pass switch.4 cover transformers at the beginning of DEI company of the U.S. 1996, are developed every straight device; The parameter development providing according to SIEMENS company again for 2003 10 cover transformers every straight device, and for the transformer near a HVDC terminal station of India.This installs by 1 4000uF(50Hz) form every straight/logical alternating current container and 2 groups of antiparallel large current bypass passages and mechanical switch bypass.
There is D.C. magnetic biasing problem in China's power network.In two groups of 500kVA main transformers of Changzhou Wu Nan transformer station in the upper river of Jiangsu 500kV main transformer, the flat 500kV DC transmission system of Three Gorges dragon's fountain-Jiangsu political affairs, expensive wide DC line, spring city station owner's transformer is all subject to the impact of D.C. magnetic biasing.Applicant carried out the research about D.C. magnetic biasing problem since 1996, had once analyzed the D.C. magnetic biasing problem (2-11 ampere bias current detected, cause the noise up to 90 decibels) of 220,000 volts of 180,000 kilovolt-amperes of power transformers appearance of Fushun power office triumph primary station in 2007.D.C. magnetic biasing problem more and more obtains the extensive concern of Chinese scholar, and many scholars also conduct a research and develop compensation arrangement D.C. magnetic biasing problem for many years.Tsing-Hua University has proposed the inhibition of a kind of small resistor device for transformer neutral point DC magnetic biasing.This device is mainly made up of a noninductive resistance and gap, and has carried out at the scene installation and checkout in 2005, has positive effect to suppressing Transformer's Neutral Line Direct Current.Have scholar to introduce the method for transformer neutral point injection reverse dc, its cardinal principle is that power supply injects reverse dc through the auxiliary earth utmost point and transformer neutral point loop to transformer neutral point through silicon rectifier again after voltage regulator.Within 2007, there is scholar to propose a kind of new method of the inspection of the school based on potential compensation principle transformer neutral point DC current, its principle is a small resistor of series connection in the middle of the transformer neutral line, on this resistance, form a dc point position by external power source, regulate the dc point position of transformer neutral point to reach the object that reduces inflow transformer winding direct current with this.Domesticly also carry out the research and development work of electric capacity every straight device.The colleges and universities such as North China Electric Power University, Xi'an Communications University, Zhejiang University also all do a lot of work, and have effectively suppressed the impact of transformer DC magnetic bias.
But all there is certain problem in the whole bag of tricks.Small resistor current limliting method cannot be eliminated neutral point direct current completely, sometimes has to adopt the resistance of larger resistance, likely affects main transformer neutral point insulation intensity; Although electric capacity can be eliminated neutral point direct current preferably every straight method, affects the effective grounding of transformer, higher to main transformer neutral point insulation requirement of strength, reply short circuit malfunction ability is poor; Neutral point injects reverse current lambda limiting process need to build the compensation of ground utmost point in addition, and choosing of compensation earth polar is extremely difficult.And at remote conveying electric system, the efficiency of offset current will reduce, and the power of DC generator will double, earth mat burden has also been increased the weight of in large electric inflow place, accelerates ground net corrosion, and application cost is high; Potential compensation method power consumption is large, install more expensive, compensation earth polar choose also more difficult.
Summary of the invention
Goal of the invention:
The utility model provides a kind of novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently, for realizing the conversion of two-phase magnetic material, by this function, for having the novel electric power transformer of D.C. magnetic biasing and no-power compensation function concurrently, object is to realize inductance adjustable, reactive power compensation and suppress transformer DC magnetic bias problem continuously.
Technical scheme:
The utility model is implemented by the following technical programs:
A kind of novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently, be connected with the novel electric power transformer with D.C. magnetic biasing compensate function, it is characterized in that: described system is mainly by the equiva lent impedance being connected with electrical network three phase mains, PWM controlled rectifier, electric capacity, single-phase inverter, the forward control contactor that magnetizes, control contactor oppositely magnetizes, demagnetization control contactor forms, equiva lent impedance connects PWM controlled rectifier, PWM controlled rectifier connects single-phase inverter, magnetize control contactor and the control contactor that oppositely magnetizes of forward is connected with PWM controlled rectifier, demagnetization control contactor connects single-phase inverter, single-phase inverter with after Capacitance parallel connection, be connected compensation control winding, PWM controlled rectifier, single-phase inverter, forward magnetize control contactor, oppositely magnetize control contactor, demagnetization control contactor be all connected with CPU, have in the transformer of D.C. magnetic biasing compensate function be provided with two-phase magnetic material, winding and Hall current sensor are controlled in compensation, compensation is controlled winding technique and is connected on two-phase magnetic material and with control system, Hall current sensor is connected with CPU.
PWM controlled rectifier is that the three-phase bridge being made up of an IGBT and the first fly-wheel diode connects to form.
Single-phase inverter is that the single-phase bridge being made up of the 2nd IGBT and the second fly-wheel diode connects to form.
Brief description of the drawings
Fig. 1 is structural representation of the present utility model.
Description of reference numerals:
1, three phase mains, 2, equiva lent impedance, 3, PWM controlled rectifier, 4, electric capacity, 5, single-phase inverter, 6, the forward control contactor that magnetizes, 7, the control contactor that oppositely magnetizes, 8, demagnetization control contactor, 9, CPU, 10, transformer, 11, two-phase magnetic material, 12, compensation, control winding, 13, Hall current sensor, 14, an IGBT, 15, the first fly-wheel diode, 16, the 2nd IGBT, 17, the second fly-wheel diode.
embodiment:
Below in conjunction with accompanying drawing, the utility model is specifically described:
The utility model is a kind of novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently, be connected with the novel electric power transformer 10 with D.C. magnetic biasing compensate function, as shown in fig. 1, it is characterized in that: described control system is mainly by the equiva lent impedance 2 being connected with electrical network three phase mains 1, PWM controlled rectifier 3, electric capacity 4, single-phase inverter 5, the forward control contactor 6 that magnetizes, control contactor 7 oppositely magnetizes, demagnetization control contactor 8 forms, equiva lent impedance 2 connects PWM controlled rectifier 3, PWM controlled rectifier 3 connects single-phase inverter 5, magnetize control contactor 6 and the control contactor 7 that oppositely magnetizes of forward is connected with PWM controlled rectifier 3, demagnetization control contactor 8 connects single-phase inverter 5, compensation control winding 12 after single-phase inverter 5 is in parallel with electric capacity 4 in connection transformer 10, PWM controlled rectifier 3, single-phase inverter 5, forward magnetize control contactor 6, oppositely magnetize control contactor 7, demagnetization control contactor 8 be all connected with CPU 9, have in the transformer 10 of D.C. magnetic biasing compensate function be provided with two-phase magnetic material 11, winding 12 and Hall current sensor 13 are controlled in compensation, compensation control winding 12 is wound on two-phase magnetic material 11 and with control system and is connected, and Hall current sensor 13 is connected with CPU 9.
PWM controlled rectifier 3 is that the three-phase bridge being made up of an IGBT 14 and the first fly-wheel diode 15 connects to form.
Single-phase inverter 5 is that the single-phase bridge being made up of the 2nd IGBT 16 and the second fly-wheel diode 17 connects to form.
The utility model CPU9 adopts Control-oriented class TMS320 series DSP chip as TMS320C24x/F24x, TMS320F28xx, the utility model is adopted 32 fixed-point DSP chip of the existing TMS320F2812 high performance-price ratio of experiment, improve system stability, also reduced the development cost of system simultaneously.
This control system can realize the characteristic conversion of two-phase magnetic material 11, the i.e. conversion of Hard Magnetic characteristic and soft magnetic characteristic.Two-phase magnetic material 11 presents soft magnetic characteristic at first, in the time that two-phase magnetic material 11 need to carry out magnetic characteristic conversion, sends high-frequency pulse signal by control system, and two-phase magnetic material 11 is magnetized, and two-phase magnetic material 11 can present Hard Magnetic characteristic; In like manner, when two-phase magnetic material 11 is demagnetized to processing, two-phase magnetic material 11 can return to again initial condition and present soft magnetic characteristic.
Operation principle of the present utility model:
Have the novel electric power transformer control system operation principle of D.C. magnetic biasing and no-power compensation function concurrently: in the time thering is the novel electric power transformer 10 of D.C. magnetic biasing compensate function D.C. magnetic biasing occurs, because making transformer core magnetic flux, bias current changes, by Hall current sensor 13, bias current (magnetic flux) is detected, the signal detecting is sent into CPU 9, CPU 9 controls forward magnetize control contactor 6 or control contactor 7 adhesives of oppositely magnetizing, control PWM controlled rectifier 3 simultaneously and produce direct voltage, direct voltage produces offset current (magnetic flux) by controlling winding 12, this magnetic flux and magnetic bias magnetic flux equal and opposite in direction, opposite direction.Finally, CPU 9 controls magnetize control contactor 6 or the control contactor 7 that oppositely magnetizes of forward and disconnects, control PWM controlled rectifier 3 quits work simultaneously, and then reach power-off the novel electric power transformer 10 with D.C. magnetic biasing compensate function is carried out to the inhibition of D.C. magnetic biasing, complete detection and elimination to transformer DC magnetic bias phenomenon.Energy-saving effect is remarkable; In the time that D.C. magnetic biasing disappears, detection by Hall current sensor 13 to exciting current, the signal detecting is sent into CPU 9, CPU 9 controls 8 adhesives of demagnetization control contactor, and control single-phase inverter 5 and produce alternating voltage, alternating voltage produces demagnetization current (magnetic flux) by controlling winding 12, and then the conversion that two-phase magnetic material 11 is carried out from Hard Magnetic characteristic to soft magnetic characteristic.When two-phase magnetic material 11 is characterized by after soft magnetic characteristic, CPU 9 controls demagnetization control contactor 8 and disconnects, and single-phase inverter 5 quits work, and completes the whole course of work.
This novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently of the utility model, can realize the conversion between DC excitation and demagnetization function to two-phase magnetic material, and the reactive power compensation and the harmonic wave that complete electric power system suppress.Reduce electric power system loss, energy-saving effect is obvious, obtains certain economic benefit, and whole electric power system is had to great practical significance.
This control system has been utilized the function of the conversion to two-phase magnetic material magnetic characteristic, makes transformer self have the ability that suppresses D.C. magnetic biasing.Overcome the deficiency that traditional inhibition D.C. magnetic biasing method is brought, ensured the reliable ground of transformer neutral point, improved the reliability of power network and transformer safe operation, whole electric power system has been had to great practical significance.
Claims (3)
1. one kind has the novel electric power transformer control system of D.C. magnetic biasing and no-power compensation function concurrently, be connected with the novel electric power transformer (10) with D.C. magnetic biasing compensate function, it is characterized in that: described system is mainly by the equiva lent impedance (2) being connected with electrical network three phase mains (1), PWM controlled rectifier (3), electric capacity (4), single-phase inverter (5), the forward control contactor (6) that magnetizes, control contactor (7) oppositely magnetizes, demagnetization control contactor (8) forms, equiva lent impedance (2) connects PWM controlled rectifier (3), PWM controlled rectifier (3) connects single-phase inverter (5), magnetize control contactor (6) and the control contactor (7) that oppositely magnetizes of forward is connected with PWM controlled rectifier (3), demagnetization control contactor (8) connects single-phase inverter (5), after single-phase inverter (5) is in parallel with electric capacity (4), be connected compensation and control winding (12), PWM controlled rectifier (3), single-phase inverter (5), forward magnetize control contactor (6), oppositely magnetize control contactor (7), demagnetization control contactor (8) all with CPU(9) be connected, have in the transformer (10) of D.C. magnetic biasing compensate function be provided with two-phase magnetic material (11), winding (12) and Hall current sensor (13) are controlled in compensation, compensation is controlled winding (12) and is wound on two-phase magnetic material (11) above and is connected with control system, Hall current sensor (13) and CPU(9) be connected.
2. the novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently according to claim 1, is characterized in that: PWM controlled rectifier (3) is by an IGBT(14) connect to form with the three-phase bridge of the first fly-wheel diode (15) formation.
3. the novel electric power transformer control system that has D.C. magnetic biasing and no-power compensation function concurrently according to claim 1, is characterized in that: single-phase inverter (5) is by the 2nd IGBT(16) connect to form with the single-phase bridge of the second fly-wheel diode (17) formation.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420334283.9U CN203933483U (en) | 2014-06-20 | 2014-06-20 | Have the novel electric power transformer control system of D.C. magnetic biasing and no-power compensation function concurrently |
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| CN201420334283.9U CN203933483U (en) | 2014-06-20 | 2014-06-20 | Have the novel electric power transformer control system of D.C. magnetic biasing and no-power compensation function concurrently |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104022698A (en) * | 2014-06-20 | 2014-09-03 | 沈阳工业大学 | Novel power transformer control system with both direct-current magnetic bias function and reactive compensation function |
| CN112951566A (en) * | 2021-02-03 | 2021-06-11 | 陕西省地方电力(集团)有限公司延安供电分公司 | High-frequency full-control switch turn-ratio-variable current-voltage self-control transformer |
-
2014
- 2014-06-20 CN CN201420334283.9U patent/CN203933483U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104022698A (en) * | 2014-06-20 | 2014-09-03 | 沈阳工业大学 | Novel power transformer control system with both direct-current magnetic bias function and reactive compensation function |
| CN112951566A (en) * | 2021-02-03 | 2021-06-11 | 陕西省地方电力(集团)有限公司延安供电分公司 | High-frequency full-control switch turn-ratio-variable current-voltage self-control transformer |
| CN112951566B (en) * | 2021-02-03 | 2023-03-21 | 陕西省地方电力(集团)有限公司延安供电分公司 | High-frequency full-control switch turn-ratio-variable current-voltage self-control transformer |
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Granted publication date: 20141105 Termination date: 20170620 |
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| CF01 | Termination of patent right due to non-payment of annual fee |