CN103513133B - The measurement apparatus of MCR type SVC device dynamic response time and method - Google Patents
The measurement apparatus of MCR type SVC device dynamic response time and method Download PDFInfo
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Abstract
Present invention is disclosed a kind of measurement apparatus for MCR type SVC device dynamic response time and method, this device includes that voltage, current signal process circuit, advance signal modulate circuit, data collecting card, processing unit module, voltage signal processing circuit and current signal process the output signal of circuit and input advance signal modulate circuit respectively, the output signal of advance signal modulate circuit accesses data collecting card, and the output signal of data collecting card accesses processing unit module.By test busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current, MCR feeder current, after advance signal modulate circuit, carry out FFT and frequency domain power calculates, and determine that the reactive power fluctuation load excision moment is the power calculation point between 90% reactive power moment time this to total input-wire power drop, finally determine response time.This algorithm is simple, and resolution is high, and within error control 78.125 microsecond, has high real-time and high reliability.
Description
Technical field
The present invention relates to a kind of measurement apparatus and the method for MCR type SVC device dynamic response time, belong to electric measurement
Technical field.
Background technology
MCR magnet controlled reactor type SVC device is applicable to the dynamic passive compensation of 6kV 500kV AC network, including fixing
Capacitor banks (Fixed Capacitor, be called for short FC), magnet controlled reactor (Magnetically Controlled Reactor,
It is called for short MCR) and control system.MCR type SVC device have capacitive to continuously adjustabe in perceptual idle scope, produce harmonic wave little,
Be easily maintained, low cost and other advantages, act primarily as in power system phase modulation, pressure regulation, raising transmission line capability, improve static and dynamically
The effects such as stability, suppression vibration;Quality of voltage (harmonic wave, voltage fluctuation and flicker) can be improved in industrial undertaking, improve
Product quality and quantity, have obvious effect on energy efficiency.
Dynamic response time is an important technical specification of MCR type SVC device functional characteristic.Due to real system
Capacity of short circuit is different with application load background, the response time test difficulty of the MCR type SVC device that access system is run, at present
Stage all uses tests at use for laboratory standard signal, and precision and actual motion value to response time test have the biggest difference.
Yet there are no that wiring is simple, analysis precision is high, temporal resolution is high is applicable to MCR type SVC device dynamic response time
Measurement apparatus and method.
Summary of the invention
The technical problem to be solved is to provide the measurement dress being applicable to MCR type SVC device dynamic response time
Put and method.Application this method can realize the dynamic response time of the MCR type SVC device to actual motion and survey fast and accurately
Amount, and the performance of MCR type SVC device is carried out science evaluate accurately.
To achieve these goals, the technical solution used in the present invention is:
Measurement apparatus for MCR type SVC device dynamic response time includes at voltage signal processing circuit, current signal
Reason circuit, advance signal modulate circuit, data collecting card, processing unit module, at voltage signal processing circuit and current signal
The output signal of reason circuit inputs advance signal modulate circuit respectively, and the output signal of advance signal modulate circuit accesses data acquisition
Truck, the output signal of data collecting card accesses processing unit module.Data collecting card is PCMCIA data collecting card, data acquisition
The sample rate of truck is 200K/s.Processing unit module is the computer running and having DAP.
Advance signal modulate circuit includes forceful electric power and light current light-coupled isolation unit and anti-aliasing filter unit, forceful electric power and light current
The output signal input anti-aliasing filter unit of light-coupled isolation unit, the output signal of anti-aliasing filter unit accesses voltage x current
Signal conversion unit.
Measuring method for MCR type SVC device dynamic response time comprises the steps:
1) the measurement point of test MCR type SVC device response time is arranged;
2) to busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current and MCR feeder current synchro measure, survey
Amount data complete the conversion of analog quantity and digital quantity by advance signal modulate circuit and high-speed figure capture card;
3) voltage signal and the current signal of standard are produced by standard signal source, to measurement apparatus hardware circuit and collection
The non-synchronous sampling errors that card produces carries out synchronicity correction;
4) use fast discrete Fourier mapping algorithm, complete busbar voltage, total input-wire electric current, the feedback of reactive power fluctuation load
Line current and 256 point Fourier conversion of MCR feeder current signal, obtain busbar voltage, total input-wire electric current, reactive power fluctuation load
Feeder current and the fundamental voltage amplitude of MCR feeder current signal and phase place;
5) complete total input-wire electric current, reactive power fluctuation load feeder electric current and the meter of MCR feeder current signal fundamental power
Calculate, busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current and MCR feeder current signal are carried out every cycle 256 point
Fourier transform obtains fundamental voltage and the amplitude of electric current and phase place, calculates total input-wire electric current, reactive power fluctuation load feeder respectively
Electric current and MCR feeder current signal active power and reactive power;
6) complete the measurement of MCR type SVC device dynamic response time τ, utilize power measurement be calculated total input-wire without
Merit power, reactive power fluctuation load feeder reactive power and MCR feeder line reactive power data carry out markers to mark, analyze total input-wire without
Merit power and MCR feeder line reactive power variation tendency, measure the response time of MCR type SVC device.
Wherein step 6 particularly as follows:
1) determine that reactive power fluctuation load excises the moment in moment t=0;
2) determining transitional processes, this process is that total input-wire reactive power drops to the idle of reactive power fluctuation load excision moment
The 10% of power, i.e. Qj(τ)=10% × Q;The reactive power of MCR feeder line rises to 90% moment of full capacity reactive power,
I.e. QMCR(τ)=90% × Q;
3) determine power calculation point n, and to calculate MCR type SVC device dynamic response time be τ=n × TS=n × 78.125
Microsecond, wherein TSFor the sampling interval.
Busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current and MCR feeder current are carried out by the method
The formula of FFT is:
Being fundametal compoment during h=1, sliding time window width chooses 256 point sampling points all the time, and the counting period is each sampling
Point sampling cycle 78.125 microsecond.
In the method, the frequency domain power calculating to total input-wire, reactive power fluctuation load feeder and MCR feeder line includes active power
With the calculating of reactive power, the counting period is 78.125 microseconds, and computing formula is:
Wherein P is the total active power of three-phase, PA(1),PB(1),PC(1) being respectively the active power of A, B, C three-phase, Q is three
Total reactive power, Q mutuallyA(1),QB(1),QC(1) reactive power of A, B, C three-phase, U it are respectivelyA(1),UB(1),UC(1) it is respectively
A, B, C three-phase voltage signal amplitude, IA(1),IB(1),IC(1) it is respectively A, B, C three-phase current signal amplitude, θA1,θB1,θC1Point
Not Wei A, B, C three-phase voltage signal phase place,It is respectively A, B, C three-phase current signal phase place.
Put into operation when SVC device is load operation, always compensate for during load operation.
Compared with prior art, the present invention has that wiring is simple, analysis precision is high, temporal resolution is high and high reliability
Feature:
(1) 3 measuring points are only set and can complete the measurement of MCR type SVC device dynamic response time.
(2) the inventive method have employed high speed digital sample, and 200k/s sample rate ensures the employing of each channel sample point
Interval time is 78.125 microseconds, and the asynchronous sampling simultaneously caused hardware circuit and capture card carries out numeral correction, strictly
Ensure that the measurement temporal resolution to MCR type SVC device dynamic response time is high, within error control 78.125 microsecond.
(3) the inventive method uses FFT theoretical and frequency domain power computational theory, and calculating total input-wire is idle, reactive power fluctuation is born
Lotus feeder line and MCR (magnet controlled reactor) feeder line reactive power, power calculation time interval is 78.125 microseconds, from computational methods
Ensure the high real-time of measurement, high accuracy and the high reliability of MCR type SVC device dynamic response time.
(4) the inventive method finally measurement to MCR type SVC device dynamic response time only need to calculate reactive power fluctuation load
After excision, total input-wire reactive power drops to the calculating of 10%MCR full capacity and counts, and algorithm is simple.
Accompanying drawing explanation
The hardware designs schematic diagram of Fig. 1 measurement apparatus;
The advance signal modulate circuit of Fig. 2 measurement apparatus;
The point layout figure of Fig. 3 MCR type SVC device response time test;
The calculation process of Fig. 4 MCR type SVC device dynamic response;
Total First Harmonic Reactive Power test of 110 tons of refining furnace power supply-distribution system total input-wires of Fig. 5, MCR feeder line and refining furnace feeder line;
The response time test of 110 tons of refining furnace MCR type SVC device of Fig. 6.
Detailed description of the invention
Below against accompanying drawing, by the description to embodiment, each component that the detailed description of the invention of the present invention is the most involved
Shape, structure, mutual alignment between each several part and annexation, the effect of each several part and operation principle, manufacturing process and
Operate with method etc., be described in further detail, to help those skilled in the art to the inventive concept of the present invention, technology
Scheme has more complete, accurate and deep understanding.
Hardware architecture diagram sees Fig. 1, and advance signal modulate circuit is shown in Fig. 2.This measuring method and device are by voltage electricity
Stream signal processing circuit, voltage and current signal advance signal modulate circuit (forceful electric power and light current light-coupled isolation, anti-aliasing filter),
PCMCIA data collecting card, computer, DAP form.
This measurement apparatus completes 1 road three-phase bus voltage and 3 road three-phase current signals (busbar voltage, total input-wire electric current, nothing
Merit fluctuating load feeder current and MCR feeder current) synchro measure, by advance signal modulate circuit, by the voltage measured and electricity
Stream signal is through the light-coupled isolation of strong and weak electricity and dividing potential drop, and forms the voltage x current of each test point shown in Fig. 3 through anti-aliasing filter
Analogue signal (Ua、Ub、Uc、 );Filter in Fig. 3
Ripple device branch road 1,2,3 is the part in power quality controlling device MCR.The frequency of power system is 50Hz, and the cycle is 0.02s,
One periodic sampling 256 point, the sampling period is 78.125 microseconds, and sample frequency is just for 12.8k/s, and the sample rate of capture card is wanted
Higher than sample frequency, so this device selects to complete each signal by the PCMCIA high-speed figure capture card that sample rate is 200K/s
The data sampling that passage is 256, obtains the digital signal (U of the voltage x current of each test point shown in Fig. 3a(n)、Ub(n)、Uc(n)、 )。
Voltage signal and the current signal of standard is produced, to measurement apparatus hardware circuit and capture card by standard signal source
The error of the non-synchronous sampling produced carries out synchronicity correction, strict guarantee 12 road voltage and current signal Domain Synchronous.
The layout of measurement apparatus test point of the present invention is shown in Fig. 3, the total input-wire of respectively MCR type SVC device access system point
Three-phase voltage u (t), total input-wire three-phase current i1(t), reactive power fluctuation load feeder three-phase current i2(t) and MCR (magnet controlled reactor
Branch current) the three-phase current i of feeder line3(t)。
The computational methods of measurement apparatus of the present invention.
256 point Fourier transformation calculations formula of the digital signal of (1) 1 road three-phase voltage and 3 road three-phase currents are as follows:
Being fundametal compoment during h=1, sliding time window width chooses 256 point sampling points all the time, and the counting period is each sampling
Point sampling cycle 78.125 microsecond, can obtain 1 road three-phase voltage signal and 3 road current signals fundamental voltage amplitude and phase place.
(2) total input-wire, reactive power fluctuation load feeder and the active power of MCR feeder line and the calculating of reactive power
Fundamental voltage according to every 256 FFT of cycle and the amplitude of electric current and phase place, calculate total input-wire, nothing respectively
Merit fluctuating load feeder line and the active power of MCR feeder line 3 road current signal and reactive power, the counting period is that each sampled point is adopted
Sample cycle 78.125 microsecond, computing formula is shown in formula (2) and formula (3):
Wherein P is the total active power of three-phase, PA(1),PB(1),PC(1) being respectively the active power of A, B, C three-phase, Q is three
Total reactive power, Q mutuallyA(1),QB(1),QC(1) reactive power of A, B, C three-phase, U it are respectivelyA(1),UB(1),UC(1) it is respectively
A, B, C three-phase voltage signal amplitude, IA(1),IB(1),IC(1) it is respectively A, B, C three-phase current signal amplitude, θA,1,θB,1,θC,1
It is respectively A, B, C three-phase voltage signal phase place,It is respectively A, B, C three-phase current signal phase place.
(3) MCR type SVC device dynamic response time τ calculates
The calculation process of MCR type SVC device dynamic response time τ is shown in Fig. 4.
Utilize power measurement and be calculated total input-wire reactive power, reactive power fluctuation load feeder reactive power and MCR feedback
Line reactive power data carry out markers to mark, analyze total input-wire reactive power and MCR feeder line reactive power variation tendency, measure
The response time of MCR type SVC device.
If the capacity of MCR type SVC device is Q, under reactive power fluctuation load oepration at full load operating mode, now MCR type SVC
The FC part full capacity Q output of device, and MCR part does not export perceptual idle QMCR=0.
Excision reactive power fluctuation load to make this moment be t=0.Now, reactive power fluctuation load PL(0)=0, QL(0)=0, always
Inlet wire Pj(0)=0, Qj(0)=Q, MCR branch road sends the most rapidly lagging reactive power, to balance FC part
Capacitive reactive power, finally realizes QFC=QMCR, MCR reaches full capacity Q output.
Utilize total input-wire reactive power, reactive power fluctuation load feeder reactive power and MCR feeder line that power calculation obtains without
Merit power data carries out markers to mark, to excise reactive power fluctuation load moment as t=0, drops to according to total input-wire reactive power
The 10% of fluctuating load excision moment, i.e. Qj(τ)=10% × Q;When the reactive power of MCR feeder line rises to the 90% of full capacity
Carve, i.e. QMCR(τ)=90% × Q.
Calculate the power calculation of this transient process to count n, then the dynamic response time of MCR type SVC device be τ=n ×
TS=n × 78.125 microsecond, wherein TSSampling interval.
Fig. 5 is 110 tons of refining furnace power supply-distribution system total input-wires, MCR feeder line and total First Harmonic Reactive Power of refining furnace feeder line
Test.
Fig. 6 is the response time test of 110 tons of refining furnace MCR type SVC device.
Above in conjunction with accompanying drawing, the present invention is exemplarily described, it is clear that the present invention implements not by aforesaid way
Restriction, as long as have employed the method design of the present invention and the improvement of various unsubstantialities that technical scheme is carried out, or without changing
Enter and design and the technical scheme of the present invention are directly applied to other occasion, all within protection scope of the present invention.
Claims (3)
1. the measuring method of a MCR type SVC device dynamic response time, it is characterised in that: the method comprises the following steps:
Step one, the measurement point of layout test MCR type SVC device response time;
Step 2, to busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current and the synchro measure of MCR feeder current,
Measurement data completes the analog quantity conversion to digital quantity by advance signal modulate circuit and data collecting card;
Step 3, produce the voltage signal of standard and current signal by standard signal source, to measurement apparatus hardware circuit sum
The non-synchronous sampling errors produced according to capture card carries out synchronicity correction;
Step 4, utilization fast discrete Fourier mapping algorithm, complete busbar voltage, total input-wire electric current, reactive power fluctuation load
256 point Fouriers conversion of feeder current and MCR feeder current signal, obtain busbar voltage, total input-wire electric current, reactive power fluctuation are born
Lotus feeder current and the fundamental voltage amplitude of MCR feeder current signal and phase place;
Step 5, complete total input-wire electric current, reactive power fluctuation load feeder electric current and the meter of MCR feeder current signal fundamental power
Calculate, busbar voltage, total input-wire electric current, reactive power fluctuation load feeder electric current and MCR feeder current signal are carried out every cycle 256 point
Fourier transform obtains fundamental voltage and the amplitude of electric current and phase place, calculates total input-wire electric current, reactive power fluctuation load feeder respectively
Electric current and MCR feeder current signal active power and reactive power;
Step 6, complete the measurement of MCR type SVC device dynamic response time τ, utilize power measurement be calculated total input-wire without
Merit power, reactive power fluctuation load feeder reactive power and MCR feeder line reactive power data, and carry out markers to mark, analyze always to enter
Line reactive power and MCR feeder line reactive power variation tendency, measure the response time of MCR type SVC device.
Measuring method the most according to claim 1, it is characterised in that: described step 6 comprises the following steps:
1) determine that the reactive power fluctuation load excision moment is the t=0 moment;
2) determining transient process, this process is the reactive power that total input-wire reactive power drops to the reactive power fluctuation load excision moment
10%, the reactive power of MCR feeder line rises to 90% moment of full capacity reactive power;
3) determine power calculation point n, and calculate MCR type SVC device dynamic response time τ=n × TS=n × 78.125 microsecond, its
Middle TSFor the sampling interval.
Measuring method the most according to claim 1, it is characterised in that: to total input-wire electric current, reactive power fluctuation load feeder electricity
Stream and MCR feeder current signal active power and the calculating of reactive power, the counting period is 78.125 microseconds, and computing formula is:
Wherein P is the total active power of three-phase, PA(1),PB(1),PC(1) being respectively the active power of A, B, C three-phase, Q is that three-phase is total
Reactive power, QA(1),QB(1),QC(1) reactive power of A, B, C three-phase, U it are respectivelyA(1),UB(1),UC(1) be respectively A, B,
C three-phase voltage signal amplitude, IA(1),IB(1),IC(1) it is respectively A, B, C three-phase current signal amplitude, θA,1,θB,1,θC,1Respectively
For A, B, C three-phase voltage signal phase place,It is respectively A, B, C three-phase current signal phase place.
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CN105388372B (en) * | 2015-10-23 | 2018-08-28 | 中国电力科学研究院 | A kind of Reactive Compensation in Wind Farm device dynamic response time detection method |
CN105319469B (en) * | 2015-11-24 | 2018-03-16 | 中国人民解放军63655部队 | A kind of thermistor dynamic characteristic measuring device and method |
CN106199286B (en) * | 2016-08-20 | 2019-01-11 | 国网山西省电力公司电力科学研究院 | Wind power plant dynamic reactive compensation device response speed test method |
CN109976298A (en) * | 2017-12-27 | 2019-07-05 | 核动力运行研究所 | A kind of fast response time tester and method based on error compensation |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101888090A (en) * | 2010-07-16 | 2010-11-17 | 东北大学 | Static reactive power compensation device based on energy method and control method thereof |
CN201708550U (en) * | 2010-05-12 | 2011-01-12 | 山东齐林电科电力设备制造有限公司 | Magnetic-control dynamic filtering MSVC flexible compensating device |
CN202103431U (en) * | 2011-06-17 | 2012-01-04 | 平阴县供电公司 | MCR (Magnetically Controlled Reactor)-type static var compensator (SVC) |
-
2013
- 2013-09-27 CN CN201310449599.2A patent/CN103513133B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN201708550U (en) * | 2010-05-12 | 2011-01-12 | 山东齐林电科电力设备制造有限公司 | Magnetic-control dynamic filtering MSVC flexible compensating device |
CN101888090A (en) * | 2010-07-16 | 2010-11-17 | 东北大学 | Static reactive power compensation device based on energy method and control method thereof |
CN202103431U (en) * | 2011-06-17 | 2012-01-04 | 平阴县供电公司 | MCR (Magnetically Controlled Reactor)-type static var compensator (SVC) |
Non-Patent Citations (3)
Title |
---|
Wind Farm Dynamic Reactive Power Compensation Device performance comparative Analysis;Runqing Bai 等;《IEEE PES ISGT ASIA 2012》;20121231;第1-4页 * |
几种静止型动态无功补偿(SVC)装置的性能及应用场合分析;江少成 等;《浙江电力》;20091231;第32-36、44页 * |
静止无功补偿器时间特性及系统级可控电流源模型研究;张超 等;《电工电能新技术》;20111031;第30卷(第4期);第1-4页 * |
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