CN1387048A - Method and device for judging phase order of 3-phase AC - Google Patents

Method and device for judging phase order of 3-phase AC Download PDF

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Publication number
CN1387048A
CN1387048A CN 02118647 CN02118647A CN1387048A CN 1387048 A CN1387048 A CN 1387048A CN 02118647 CN02118647 CN 02118647 CN 02118647 A CN02118647 A CN 02118647A CN 1387048 A CN1387048 A CN 1387048A
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phase
rotating vector
angle
voltage
current
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CN1159593C (en
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刘平
万和平
杨志洵
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Vertiv Tech Co Ltd
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Emerson Network Power Co Ltd
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Abstract

A method and device for judging the phase sequence of three-phase AC is characterized by use of the rotation direction of rotary vector angles to determine the phase sequence. Said method incldues sampling the real-time three-phase voltage/current signals, finding out the phase angle difference of the rotary voltage/current vectors, calculating the phase angle difference in a certain time, and determining the rotation directions of rotary vector angles according to the signs of said phase angle differences. Its advantages are high anti-interference power and high correctness.

Description

Phase order of 3-phase AC determination methods and device
Technical field
The present invention relates to measure the method and the device of electric variable, relate in particular to a kind of phase order of 3-phase AC determination methods and device.
Background technology
The normal operation of three phase supply equipment and the phase sequence of three-phase electricity are closely bound up, and as lathe etc., so the correct detection of three-phase electricity phase sequence is the basic demand of a lot of three-phase equipments.
Mainly contain two kinds of methods in the existing phase sequence measuring technique:
Method 1: by the unbalance load of phase sequence measurement mechanism structure, cause each phase voltage imbalance of circuit of testing the phase sequence threephase load, magnitude relationship with unbalance voltage embodies by display device simultaneously, because phase sequence is not simultaneously, phase voltage magnitude relationship on same two phase loads is opposite, can judge phase sequence in view of the above.As shown in Figure 1, be the circuit diagram of a phase sequence test pencil, this method may cause erroneous judgement when severe three-phase is uneven.
Method 2: utilize the feature of three-phase alternating current instantaneous voltage waveform, in each phase place of preset time interval alternate sweep; Calculate measured value by a kind of suitable predetermined method of determining and calculating, or the symbol of only calculating the measured value in two moment is determined phase sequence, as shown in Figure 2, measure the three phase network signal with about 3 times of survey frequencies to mains frequency, the measured value symbolic information that obtains according to two sampling instants, can judge the positive and negative of phase sequence, this method is based on waveform character in essence, and the quality of waveform is influential to the accuracy of measurement result.
Summary of the invention
One of purpose of the present invention is to overcome the deficiencies in the prior art and defective, provides a kind of antijamming capability strong phase order of 3-phase AC determination methods.
Two of purpose of the present invention is to provide the phase order of 3-phase AC judgment means of the above-mentioned phase sequence determination methods of a kind of usefulness.
The method that is adopted among the present invention is: the phase sequence of determining three-phase alternating current according to the sense of rotation at rotating vector angle.
The sense of rotation at described rotating vector angle is by gathering three-phase real-time voltage/current signal, ask for the phase angle difference of voltage/current rotating vector, calculate the rotating vector phase angle difference between the certain hour interval, determine the sense of rotation at rotating vector angle according to the symbol of the rotating vector phase angle difference of being calculated;
The sense of rotation at described rotating vector angle can be determined by calculating in the rotating vector phase angle difference of a civil power between the cycle;
Described rotating vector phase angle is by the voltage/current signals coordinate transform of three-phase to two-phase, adopts formula:
X α=(2X a-X b-X c)/3
X β=(X b-X c)/3 1/2
Obtain the instantaneous value X of rotating vector at two phase coordinate systems α, X β, X wherein a, X b, X cBe the three-phase signal value of voltage/current, calculating parameter rotating vector mould is long:
X m=(X α 2+X β 2) 1/2
According to the instantaneous value X of rotating vector at two phase coordinate systems α, X βCalculate the rotating vector angle θ of corresponding panoramic limit, then, current rotating vector angle θ iDeduct the rotating vector angle θ in a time interval I-1, get phase angle difference Δ θ, determine the sense of rotation of rotating vector angle θ according to the symbol of phase angle difference Δ θ;
Described rotating vector angle θ is according to θ=arccos (X α/ X m) or θ=arcsin (X β/ X m) calculate, its quadrature of living in is by X αAnd X βThe polarity discriminating of value;
After can or averaging through Filtering Processing, described phase angle difference Δ θ can obtain accurate stable data.
The phase order of 3-phase AC judgment means of the above-mentioned phase sequence determination methods of a kind of usefulness, comprise: sample circuit, level shift circuit, AD sample circuit and sequence judging circuit, described sample circuit is used to receive each cross streams voltage/current of three-phase alternating current, through level shift circuit AC signal is processed into direct current signal then, each phase direct current signal of gained is through the AD sample circuit, get three-phase real-time voltage/electric current input sequence judging circuit after the analog to digital conversion, described sequence judging circuit calculates the rotating vector phase angle difference between the certain hour interval, determines the sense of rotation at rotating vector angle according to the symbol of the rotating vector phase angle difference of being calculated.
Know-why of the present invention and beneficial effect are: rotating vector is the result of three-phase electricity through the PARK conversion, for three-phase ac signal, can do following statement:
X=2/3*(X a+X be j2π/3+x ce -j2π/3)
X wherein a, x b, x cCan represent any three phase variables, if the balance three-phase electricity is arranged, then
X a=X mcosωt
X b=X mcos(ω)t-2π/3)
X c=X mcos(ωt+2π/3)
Then: X=X me J ω t
When three-phase equilibrium voltage or electric current are the space vector of a rotation after above-mentioned conversion, the direction of vector rotation is relevant with phase sequence, this phase sequence measuring method relies on the rotating vector sense of rotation to determine, sense of rotation from the rotating vector angle of the three-phase alternating current of integral body, sense of rotation is certain, therefore the symbol of phase angle difference is only relevant with phase sequence, has guaranteed the accuracy that phase sequence detects from principle.
For the alternating current of three-phase imbalance, as shown in Figure 3, being embodied in has shake slightly on the mould value of rotating vector, but the sense of rotation at rotating vector angle is not impacted.
Even if for harmonic content when higher, rotating vector end points movement locus as shown in Figure 4, vector has the situation of reverse rotation in rotary course, but at a civil power in the cycle, the angle that rotating vector turns over still is positive 2 π or negative 2 π, the sense of rotation that promptly is presented as the rotating vector angle of whole three-phase alternating current is certain, and therefore, the accuracy that phase sequence is judged still can be guaranteed.
So, use this method of judging phase sequence by the sense of rotation at rotating vector angle, make the stability in three-phase signal source not influence measurement result, when even the electric signal imbalance in three-phase signal source even harmonic content are higher, also can obtain reliable result, therefore this method antijamming capability is strong, and the method that the present invention uses makes that the judgement of phase sequence only is the inevitable outcome of voltage or current measurement, additional resource is few, has stronger applicability; Because the abnormal conditions potentially unstable of each sampling period virtual voltage, phase angle difference can obtain accurate stable data after can or averaging through Filtering Processing, has so just further guaranteed the reliability of data, makes result of determination more accurate.
In a word, the invention provides the strong phase order of 3-phase AC determination methods of a kind of antijamming capability, applicability is strong, and result of determination is accurate.
Description of drawings
Fig. 1 is the circuit diagram of existing a kind of phase sequence test pencil;
Fig. 2 is the synoptic diagram of existing a kind of three phase network signal measurement phase sequence;
Fig. 3 is unbalanced alternating current rotating vector synoptic diagram;
Fig. 4 is the higher alternating current rotating vector synoptic diagram of harmonic content;
Fig. 5 is a schematic flow sheet of the present invention;
Fig. 6 is the application example electrical block diagram.
Embodiment
Further describe the specific embodiment of the present invention below in conjunction with drawings and Examples.
As shown in Figure 5, the sense of rotation measuring method of rotating vector of the present invention is:
The rotating vector phase angle theta is by the voltage/current signals coordinate transform of three-phase to two-phase, adopts formula:
X α=(2X a-X b-X c)/3
X β=(X b-X c)/3 1/2
Obtain the instantaneous value X of rotating vector at two phase coordinate systems α, X β, X wherein a, X b, X cBe the three-phase signal value of voltage/current, calculating parameter rotating vector mould is long:
X m=(X α 2+X β 2) 1/2
According to the instantaneous value X of rotating vector at two phase coordinate systems α, X βCalculate the rotating vector angle θ of corresponding panoramic limit, rotating vector angle θ is according to θ=arccos (X α/ X m) or θ=arcsin (X β/ X m) calculate, its quadrature of living in is by X αAnd X βThe polarity discriminating of value; Then, current rotating vector angle θ iDeduct the rotating vector angle θ in a time interval I-1, phase angle difference Δ θ, determine the sense of rotation of rotating vector angle θ according to the symbol of phase angle difference Δ θ, so just determine the phase sequence of three-phase alternating current according to the sense of rotation of rotating vector angle θ.
When making in this way, can calculate at the rotating vector phase angle difference Δ θ of a civil power between the cycle, phase angle difference Δ θ should be positive 2 π or negative 2 π, thereby determines the phase sequence of three-phase alternating current.
If the time interval of calculating phase angle difference, phase angle difference Δ θ can obtain accurate stable data through Filtering Processing or after averaging less than a civil power cycle.
Lift application application example of the present invention below and describe, be illustrated in figure 6 as this application example electrical block diagram, wherein, u ABe three phase network A cross streams voltage;
u BBe three phase network B cross streams voltage;
u CBe three phase network C cross streams voltage;
U ' ABe the voltage of three phase network A cross streams electricity after step-down;
U ' BBe the voltage of three phase network B cross streams electricity after step-down;
U ' CBe the voltage of three phase network C cross streams electricity after step-down;
U " ABe the signal behind the A phase sinusoidal voltage stack direct current;
U " BBe the signal behind the B phase sinusoidal voltage stack direct current;
U " CBe the signal behind the C phase sinusoidal voltage stack direct current;
Va is the instantaneous sampling signal of A cross streams voltage;
Vb is the instantaneous sampling signal of B cross streams voltage;
Vc is the instantaneous sampling signal of C cross streams voltage.
Comprise sample circuit 61 in this application example, level shift circuit 62, AD sample circuit 63 and sequence judging circuit 64, sample circuit 61 is used to receive each cross streams voltage/current of three-phase alternating current, voltage sampling circuit 61 can adopt voltage divider or voltage transformer (VT), receives each cross streams voltage u of three-phase alternating current A, u B, u C, after voltage sampling circuit 61 step-downs, each phase voltage u ' A, u ' B, u ' CThrough level shift circuit 62, AC signal is processed into direct current signal, each phase direct current signal u of gained " A, u " B, u " CThrough AD sample circuit 63, get three-phase real-time voltage V after the analog to digital conversion a, V b, V cInput sequence judging circuit 64, because sampled signal is a voltage signal, three-phase real-time voltage V a, V b, V cBe the instantaneous value X of foregoing three phase coordinate systems a, X b, X c, in this sequence judging circuit 64:
The rotating vector phase angle theta is by the voltage signal coordinate transform of three-phase to two-phase, adopts formula:
V α=(2V a-V b-V c)/3
V β=(V b-V c)/3 1/2
Obtain the instantaneous value V of rotating vector at two phase coordinate systems α, V β, instantaneous value V herein α, V βThe three-phase alternating current voltage signal is gathered in representative, with aforesaid instantaneous value X α, X βEssence is identical, wherein V a, V b, V cBe the three-phase signal value of voltage, calculating parameter rotating vector mould is long:
V m=(V α 2+V β 2) 1/2
According to the instantaneous value V of rotating vector at two phase coordinate systems α, V βCalculate the rotating vector angle θ of corresponding panoramic limit, rotating vector angle θ is according to θ=arccos (V α/ V m) or θ=arcsin (V β/ V m) calculate, its quadrature of living in is by V αAnd V βThe polarity discriminating of value; Then, current rotating vector angle θ iDeduct the rotating vector angle θ in a time interval I-1, phase angle difference Δ θ, determine the sense of rotation of rotating vector angle θ according to the symbol of phase angle difference Δ θ, so just determine the phase sequence of three-phase alternating current according to the sense of rotation of rotating vector angle θ.

Claims (7)

1. a phase order of 3-phase AC determination methods is characterized in that, determines the phase sequence of three-phase alternating current according to the sense of rotation at rotating vector angle.
2. phase order of 3-phase AC determination methods according to claim 1, it is characterized in that, the sense of rotation at described rotating vector angle is by gathering three-phase real-time voltage/current signal, ask for the phase angle difference of voltage/current rotating vector, calculate the rotating vector phase angle difference between the certain hour interval, determine the sense of rotation at rotating vector angle according to the symbol of the rotating vector phase angle difference of being calculated.
3. phase order of 3-phase AC determination methods according to claim 2 is characterized in that, the sense of rotation at described rotating vector angle can be determined by calculating in the rotating vector phase angle difference of a civil power between the cycle.
4. according to claim 2 or described phase order of 3-phase AC determination methods, it is characterized in that described rotating vector angle is by the voltage/current signals coordinate transform of three-phase to two-phase, adopt formula:
X α=(2X a-X b-X c)/3
X β=(X b-X c)/3 1/2
Obtain the instantaneous value X of rotating vector at two phase coordinate systems α, X β, X wherein a, X b, X cBe the three-phase signal value of voltage/current, calculating parameter rotating vector mould is long:
X m=(X α 2+X β 2) 1/2
According to the instantaneous value X of rotating vector at two phase coordinate systems α, X βCalculate the rotating vector angle θ of corresponding panoramic limit, then, current rotating vector angle θ iDeduct the rotating vector angle θ in a time interval I-1, get phase angle difference Δ θ, determine the sense of rotation of rotating vector angle θ according to the symbol of phase angle difference Δ θ.
5. phase order of 3-phase AC determination methods according to claim 4 is characterized in that, described rotating vector angle θ is according to θ=arccos (X α/ X m) or θ=arcsin (X β/ X m) calculate, its quadrature of living in is by X αAnd X βThe polarity discriminating of value.
6. according to claim 2 or 4 described phase order of 3-phase AC determination methods, it is characterized in that described phase angle difference Δ θ can obtain accurate stable data through Filtering Processing or after averaging.
7. adopt a kind of phase order of 3-phase AC judgment means of the described phase sequence determination methods of claim 1, it is characterized in that, it comprises: sample circuit (61), level shift circuit (62), AD sample circuit (63) and sequence judging circuit (64), described sample circuit (61) is used to receive each cross streams voltage/current of three-phase alternating current, through level shift circuit (62) AC signal is processed into direct current signal then, each phase direct current signal of gained is through AD sample circuit (63), get three-phase real-time voltage/electric current input sequence judging circuit (64) after the analog to digital conversion, described sequence judging circuit (64) calculates the rotating vector phase angle difference between the certain hour interval, determines the sense of rotation at rotating vector angle according to the symbol of the rotating vector phase angle difference of being calculated.
CNB021186472A 2002-04-27 2002-04-27 Method and device for judging phase order of 3-phase AC Expired - Lifetime CN1159593C (en)

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101442255B (en) * 2008-12-31 2010-08-11 焦作市明株自动化工程有限责任公司 Three-phase/biphase coordinates conversion method for frequency changer
CN101048669B (en) * 2004-08-16 2011-04-20 埃内尔迪斯特里布齐恩公司 Method and system for detecting the phase wiring of an unknown phase voltage relative to a reference phase voltage
CN102680806A (en) * 2012-04-20 2012-09-19 京东方科技集团股份有限公司 Detection method and detection device for three-phase alternating-current phase sequence
CN103825518A (en) * 2014-03-05 2014-05-28 华侨大学 System and method for phase sequence detection and rotor initial location positioning of three-phase permanent-magnet synchronous motor
CN104502736A (en) * 2015-01-09 2015-04-08 珠海派诺科技股份有限公司 Online phase sequence self-adapting method
CN105259429A (en) * 2015-10-30 2016-01-20 厦门科华恒盛股份有限公司 Three-phase electricity phase sequence judging method
CN107803032A (en) * 2016-09-08 2018-03-16 汉斯·W·范丹埃尔岑 Motorization Climbing top Yo-Yo
CN108490275A (en) * 2018-04-08 2018-09-04 深圳鹏城新能科技有限公司 A kind of quick three-phase phase-sequence Digital Detecting Method and its device
CN109030966A (en) * 2018-08-09 2018-12-18 海南金盘智能科技股份有限公司 A kind of phase sequence detecting method of three-phase voltage, system and device
CN110869778A (en) * 2019-04-29 2020-03-06 深圳欣锐科技股份有限公司 Phase sequence detection method of three-phase power grid and related device
CN111707881A (en) * 2020-07-10 2020-09-25 陕西航空电气有限责任公司 Three-phase alternating current power supply sequence identification method and device
CN115902401A (en) * 2023-02-20 2023-04-04 深圳库马克科技有限公司 Phase detection method of power unit, and related device and medium

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101048669B (en) * 2004-08-16 2011-04-20 埃内尔迪斯特里布齐恩公司 Method and system for detecting the phase wiring of an unknown phase voltage relative to a reference phase voltage
CN101442255B (en) * 2008-12-31 2010-08-11 焦作市明株自动化工程有限责任公司 Three-phase/biphase coordinates conversion method for frequency changer
US9429604B2 (en) 2012-04-20 2016-08-30 Boe Technology Group Co., Ltd. Three-phase AC phase sequence detecting method and apparatus
CN102680806A (en) * 2012-04-20 2012-09-19 京东方科技集团股份有限公司 Detection method and detection device for three-phase alternating-current phase sequence
WO2013155844A1 (en) * 2012-04-20 2013-10-24 京东方科技集团股份有限公司 Three-phase ac phase-sequence detection method and device
CN103825518A (en) * 2014-03-05 2014-05-28 华侨大学 System and method for phase sequence detection and rotor initial location positioning of three-phase permanent-magnet synchronous motor
CN103825518B (en) * 2014-03-05 2016-01-20 华侨大学 Three-phase permanent-magnetic synchronous motors Phase sequence detection and initial position of rotor navigation system and method
CN104502736A (en) * 2015-01-09 2015-04-08 珠海派诺科技股份有限公司 Online phase sequence self-adapting method
CN104502736B (en) * 2015-01-09 2017-06-23 珠海派诺科技股份有限公司 A kind of online phase sequence self-adaption method
CN105259429A (en) * 2015-10-30 2016-01-20 厦门科华恒盛股份有限公司 Three-phase electricity phase sequence judging method
CN107803032B (en) * 2016-09-08 2021-08-03 汉斯·W·范丹埃尔岑 Motorized yo-yo
CN107803032A (en) * 2016-09-08 2018-03-16 汉斯·W·范丹埃尔岑 Motorization Climbing top Yo-Yo
CN108490275A (en) * 2018-04-08 2018-09-04 深圳鹏城新能科技有限公司 A kind of quick three-phase phase-sequence Digital Detecting Method and its device
CN109030966A (en) * 2018-08-09 2018-12-18 海南金盘智能科技股份有限公司 A kind of phase sequence detecting method of three-phase voltage, system and device
CN110869778A (en) * 2019-04-29 2020-03-06 深圳欣锐科技股份有限公司 Phase sequence detection method of three-phase power grid and related device
CN110869778B (en) * 2019-04-29 2022-02-22 深圳欣锐科技股份有限公司 Phase sequence detection method of three-phase power grid and related device
CN111707881A (en) * 2020-07-10 2020-09-25 陕西航空电气有限责任公司 Three-phase alternating current power supply sequence identification method and device
CN111707881B (en) * 2020-07-10 2022-08-19 陕西航空电气有限责任公司 Three-phase alternating current power supply sequence identification method and device
CN115902401A (en) * 2023-02-20 2023-04-04 深圳库马克科技有限公司 Phase detection method of power unit, and related device and medium

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Patentee after: Vitamin Technology Co., Ltd.

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