CN111521858A - Method for extracting double-frequency alternating current component in rotating coordinate system - Google Patents
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Abstract
The invention belongs to the field of power electronics, and particularly discloses a method for extracting a double-frequency alternating current component under a rotating coordinate system, which comprises the following steps: the device comprises a power grid voltage signal acquisition module, a synchronous rotation coordinate transformation module, a delay sampling period filtering module, an amplitude and phase calculation module and a synchronous rotation coordinate inverse transformation module. The direct current component, namely the positive sequence component, under the synchronous rotating coordinate system can be accurately obtained only by carrying out synchronous rotating coordinate transformation on the asymmetric three-phase voltage and then utilizing a delay sampling period filtering algorithm. The delay sampling period filtering module is used for rapidly separating positive sequence voltage components and negative sequence voltage components by delaying two sampling periods for the voltage components on the synchronous rotating coordinate system.
Description
Technical Field
The invention relates to the field of power electronics, in particular to a practical method for quickly and accurately extracting double-frequency alternating current components under a rotating coordinate system, which is suitable for unbalanced working conditions of a power grid.
Background
The grid voltage is unbalanced, and the stable operation of the grid-connected inverter system is greatly influenced. The method is a key problem of normal operation, high-performance control, phase detection, frequency detection and the like of a grid-connected power electronic system in rapidly and accurately acquiring the positive sequence component of the grid voltage. Under the condition of three-phase unbalanced grid voltage, the basic requirement for ensuring the normal operation of the grid-connected inverter is to rapidly and accurately acquire the positive sequence components of the voltage and the current. The three-phase unbalanced voltage is represented as a direct current component and a double frequency alternating current component on a rotating coordinate system. It is usually necessary to design a filter algorithm to filter the double-frequency ac component to extract the dc component (corresponding to the positive sequence component in the stationary coordinate system). The existing AC component suppression method mainly uses a low-pass filter, but in practical application, an ideal compromise scheme between dynamic response speed and AC attenuation capability is difficult to make. The method for eliminating the delay signal can effectively solve the problem of double-frequency fluctuation under a synchronous rotating coordinate system, but the algorithm needs to delay 1/4 power frequency cycles, so that the response time is increased. The problem of slow response speed also exists when the low-frequency components are filtered by the moving average filtering method.
Disclosure of Invention
The invention provides a method for extracting a double-frequency alternating current component in a rotating coordinate system, aiming at the defect that the extraction speed of a voltage positive sequence component under the existing unbalanced working condition is slow.
The invention is realized by the following technical scheme:
a method for extracting double-frequency alternating current component in a rotating coordinate system only needs to carry out synchronous rotating coordinate transformation on asymmetric three-phase voltage, and then a direct current component, namely a positive sequence component, in the synchronous rotating coordinate system can be accurately obtained by utilizing a delay sampling period filtering algorithm. The delayed sampling period filtering algorithm rapidly separates positive sequence voltage components from negative sequence voltage components by delaying the voltage components on the synchronous rotating coordinate system by two sampling periods.
The method can rapidly filter the double-frequency alternating current component of the unbalanced grid voltage without updating the grid frequency information in real time, and the calculation precision can meet the requirements of engineering application, so that the method is a simple and effective practical algorithm and has good application value. The technology disclosed by the invention has the advantages of high response speed, high calculation precision, simple implementation process and the like, and can realize high-performance signal detection and power equipment control in an unbalanced power grid environment. The invention relates to a method for extracting a double-frequency alternating current component in a rotating coordinate system, which comprises the following steps: the device comprises a power grid voltage signal acquisition module, a synchronous rotation coordinate transformation module, a delay sampling period filtering module, an amplitude and phase calculation module and a synchronous rotation coordinate inverse transformation module.
And the power grid voltage signal acquisition module is used for acquiring three-phase unbalanced voltage signals of the power grid voltage to obtain three-phase power grid voltage signals containing positive sequence components and negative sequence components.
And the synchronous rotating coordinate transformation module is used for carrying out synchronous rotating coordinate transformation on the three-phase power grid voltage signal containing the positive sequence component and the negative sequence component to obtain a voltage component under a two-phase rotating coordinate system.
The delay sampling period filtering module is used for respectively delaying one sampling period and two sampling periods for the voltage component under the synchronous rotating coordinate system to quickly extract a direct current component and a double-frequency alternating current component, namely a positive sequence voltage component and a negative sequence voltage component of the power grid voltage.
The double-frequency alternating current component extraction method is combined with the amplitude and phase calculation module, and the real-time amplitude and phase of the power grid voltage are calculated respectively from the direct current component voltage signals and the double-frequency alternating current component voltage signals under the two-phase rotating coordinate system. The synchronous rotation coordinate inverse transformation module is used for transforming direct-current component voltage signals and double-frequency alternating-current component voltage signals under a two-phase rotation coordinate system into positive and negative sequence component signals of three-phase power grid voltage.
The invention relates to a method for extracting a double-frequency alternating current component in a rotating coordinate system, which comprises the following steps:
(1) the unbalanced three-phase network voltage signal is composed of a positive sequence component and a negative sequence component, and the three-phase voltage can be represented by the following formula:
U＝U++U-
the positive sequence voltage component and the negative sequence voltage component have the expression:
in the formula: u. ofa、ub、ucRespectively representing a phase voltage, b phase voltage, c phase voltage, omega represents voltage angular frequency, t represents time, theta represents positive sequence voltage initial phase, represents negative sequence voltage initial phase, UmRepresenting the amplitude.
(2) Carrying out synchronous rotating coordinate transformation on the three-phase power grid voltage signal to obtain a voltage signal under a two-phase rotating coordinate system, wherein the mathematical transformation equation is as follows:
in the formula: u shapedRepresenting d-axis voltage, UqRepresenting the q-axis voltage, Tabc/dqRepresenting a synchronous rotating coordinate transformation matrix.
Wherein,
(3) obtaining the voltage component of the unbalanced three-phase voltage under the rotating coordinate system through the step (2), wherein the expression is as follows:
(4) respectively delaying the voltage components under the synchronous rotating coordinate system in the step (3) by TsAnd 2TsTo obtain Ud(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) Wherein said T issIs the sampling period. Solving for U by simultaneousd(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) And four equations can obtain the direct current component under the synchronous rotating coordinate system.
The calculation formula of k-th sampling of the direct current component under the synchronous rotating coordinate system is as follows:
(5) in the same way, step (4) is carried out, and U is solved through simultaneousd(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) Four equations can obtain the double frequency alternating current component under the synchronous rotating coordinate system.
The calculation formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotation coordinate system is as follows:
preferably, the delay sampling period filtering module includes a delay module and a delay sampling period filtering algorithm. The delay sampling period filtering module is used for rapidly extracting direct current components and double-frequency alternating current components, namely positive sequence voltage components and negative sequence voltage components of the power grid voltage by respectively delaying one sampling period and two sampling periods for voltage components in a rotating coordinate system.
The time delay sampling period filtering algorithm is realized by enabling an original signal U on a synchronous rotating coordinate system to be synchronousd/qDelaying the signal U by one sampling periodd/q(t–Ts) Delaying signal U for two sampling periodsd/q(t–2Ts) And performing mathematical operation to obtain a direct current component and a double frequency alternating current component under a synchronous rotating coordinate system.
The direct current component in the synchronous rotating coordinate system has a structural formula in k sampling:
in the formula: x is the number ofdRepresenting the d-axis component, xqRepresenting the q-axis component. The structural formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotation coordinate system is as follows:
(6) the synchronous rotation transformation matrix in the synchronous rotation coordinate transformation module in the step (4) is Tabc/dq(ωt) Wherein
preferably, the amplitude and phase calculation module calculates the real-time amplitude and phase of the grid voltage respectively from the direct current component and the double frequency alternating current component signals in the two-phase rotating coordinate system. The positive sequence component phase calculation formula of the three-phase power grid voltage is as follows:
wherein, thetaexIndicating the phase of the determination condition.
Assuming that the phase is between 0 and 2 pi, but the phase obtained by obtaining the direct current component signal under the two-phase rotating coordinate system according to the step (4) may not be in the interval, adding a judgment condition phase to enable the obtained phase to be between 0 and 2 pi, wherein the judgment condition is as follows:
the calculation formula of the voltage component amplitudes of the positive sequence and the negative sequence of the three-phase power grid voltage is as follows:
(7) the synchronous rotation coordinate inverse transformation module is used for transforming direct-current component voltage signals and double-frequency alternating-current component voltage signals under a two-phase rotation coordinate system into positive and negative sequence component signals of three-phase power grid voltage. Wherein the transformation formula is
Synchronous rotation inverse transformation matrix as Tdq/abc(ω t) wherein,
the double-frequency alternating current component extraction method can be used in the fields of grid-connected inverter control and the like, such as positive sequence component separation, power grid synchronous phase detection, power quality control, unbalanced power grid fault ride-through and the like. Compared with the prior art, the invention has the following advantages:
(1) the filtering method can filter the double-frequency alternating current component in the unbalanced power grid voltage by using the delay sampling period filtering module only by carrying out synchronous rotating coordinate transformation once, and does not need a parameter debugging process in a closed-loop detection method;
(2) the filtering method has the advantage of high response speed, and greatly shortens the dynamic response time in the filtering process;
(3) the filtering method has the advantages of simple algorithm and practicality, is mainly characterized by easy realization, and particularly obviously reduces the calculation burden;
(4) the filtering method has the advantage of less memory occupation, and meets the requirements of real-time digital control;
(5) the filtering method has the advantage of high precision, and the method cannot be changed due to the change of the sampling frequency of the detection device;
(6) through the technical scheme, when the power grid frequency fluctuates within the limit range allowed by the national standard, the method can quickly and accurately filter the double-frequency alternating current component in the unbalanced power grid without updating the power grid frequency information in real time, and the calculation precision can meet the requirements of engineering application, so that the method is a simple, effective and practical algorithm and has good application value.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of the operation of the extraction method of the present invention;
FIG. 2 is a block diagram of a delayed sample period filtering algorithm of the present invention;
FIG. 3 is a waveform of three-phase voltage signals before and after an unbalanced abrupt change according to the present invention;
FIG. 4 is a filtered front d-axis component of the present invention;
FIG. 5 is a pre-filter q-axis component of the present invention;
FIG. 6 is the filtered d-axis component of the present invention;
FIG. 7 is a filtered q-axis component of the present invention;
FIG. 8 illustrates the application of the extraction method of the present invention to positive sequence component extraction;
FIG. 9 is the positive sequence component extraction result of the extraction method of the present invention;
FIG. 10 illustrates the application of the extraction method of the present invention to synchronous phase acquisition;
fig. 11 is a result of the acquisition of the synchronization phase of the extraction method of the present invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Examples
As shown in fig. 1-11, a method for extracting a frequency-doubled ac component in a rotating coordinate system according to the present invention includes: the device comprises a power grid voltage signal acquisition module, a synchronous rotation coordinate transformation module, a delay sampling period filtering module, an amplitude and phase calculation module and a synchronous rotation coordinate inverse transformation module. The method comprises the following steps:
(1) the power grid voltage signal acquisition module acquires three-phase unbalanced voltage signals of power grid voltage to obtain three-phase power grid voltage signals containing positive sequence components and negative sequence components. The unbalanced three-phase network voltage signal is composed of a positive sequence component and a negative sequence component, and the three-phase voltage can be represented by the following formula:
U＝U++U-
the positive sequence voltage component and the negative sequence voltage component have the expression:
in the formula: u. ofa、ub、ucRespectively representing a phase voltage, b phase voltage, c phase voltage, omega represents voltage angular frequency, t represents time, theta represents positive sequence voltage initial phase, represents negative sequence voltage initial phase, UmRepresenting the amplitude.
(2) And the synchronous rotating coordinate transformation module carries out synchronous rotating coordinate transformation on the three-phase power grid voltage signal containing the positive sequence component and the negative sequence component to obtain a voltage component under a two-phase rotating coordinate system. Wherein the mathematical transformation equation is:
in the formula: u shapedRepresenting d-axis voltage, UqRepresenting the q-axis voltage, Tabc/dqRepresenting a synchronous rotating coordinate transformation matrix.
Wherein,
(3) obtaining the voltage component of the unbalanced three-phase voltage under the rotating coordinate system through the step (2), wherein the expression is as follows:
(4) the delay sampling period filtering module respectively delays one sampling period and two sampling periods for voltage components under a synchronous rotating coordinate system to quickly extract direct current components and double-frequency alternating current components, namely positive sequence voltage components and negative sequence voltage components of the power grid voltage.
Respectively delaying the voltage components under the synchronous rotating coordinate system in the step (3) by TsAnd 2TsTo obtain Ud(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) Wherein said T issIs the sampling period. Solving for U by simultaneousd(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) And four equations can obtain the direct current component under the synchronous rotating coordinate system. The calculation formula of k-th sampling of the direct current component under the synchronous rotating coordinate system is as follows:
(5) in the same way, step (4) is carried out, and U is solved through simultaneousd(t–Ts),Ud(t–2Ts),Uq(t–Ts),Uq(t–2Ts) Four equations can obtain the double frequency alternating current component under the synchronous rotating coordinate system.
The calculation formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotation coordinate system is as follows:
as shown in fig. 2, the delay sampling period filtering module includes a delay module Z and a delay sampling period filtering algorithm. The delay sampling period filtering module is used for rapidly extracting direct current components and double-frequency alternating current components, namely positive sequence voltage components and negative sequence voltage components of the power grid voltage by respectively delaying one sampling period and two sampling periods for voltage components in a rotating coordinate system.
The time delay sampling period filtering algorithm is realized by enabling an original signal U on a synchronous rotating coordinate system to be synchronousd/qDelaying the signal U by one sampling periodd/q(t–Ts) Delaying signal U for two sampling periodsd/q(t–2Ts) And performing mathematical operation to obtain a direct current component and a double frequency alternating current component under a synchronous rotating coordinate system.
The direct current component in the synchronous rotating coordinate system has a structural formula in k sampling:
in the formula: x is the number ofdRepresenting the d-axis component, xqRepresenting the q-axis component.
The structural formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotation coordinate system is as follows:
(6) the synchronous rotation transformation matrix in the synchronous rotation coordinate transformation module in the step (4) is Tabc/dq(ω t) wherein,
the amplitude and phase calculation module respectively calculates the real-time amplitude and phase of the power grid voltage according to the direct-current component signals and the double-frequency alternating-current component signals under the two-phase rotating coordinate system. The positive sequence component phase calculation formula of the three-phase power grid voltage is as follows:
wherein, thetaexIndicating the phase of the determination condition.
Assuming that the phase is between 0 and 2 pi, but the phase obtained by obtaining the direct current component signal under the two-phase rotating coordinate system according to the step (4) may not be in the interval, adding a judgment condition phase to enable the obtained phase to be between 0 and 2 pi, wherein the judgment condition is as follows:
the calculation formula of the voltage component amplitudes of the positive sequence and the negative sequence of the three-phase power grid voltage is as follows:
(7) the synchronous rotation coordinate inverse transformation module is used for transforming direct-current component voltage signals and double-frequency alternating-current component voltage signals under a two-phase rotation coordinate system into positive and negative sequence component signals of three-phase power grid voltage. Wherein, the transformation formula is as follows:
synchronous rotation inverse transformation matrix as Tdq/abc(ω t) wherein,
the double-frequency alternating current component extraction method can be used in the fields of grid-connected inverter control and the like, such as positive sequence component separation, power grid synchronous phase detection, power quality control, unbalanced power grid fault ride-through and the like.
Claims (5)
1. A method for extracting a double frequency alternating current component in a rotating coordinate system is characterized by comprising the following steps: the device comprises a power grid voltage signal acquisition module, a synchronous rotation coordinate transformation module, a delay sampling period filtering module, an amplitude and phase calculation module and a synchronous rotation coordinate inverse transformation module;
(1) the power grid voltage signal acquisition module acquires three-phase unbalanced voltage signals of power grid voltage to obtain three-phase power grid voltage signals containing positive sequence components and negative sequence components;
(2) the synchronous rotating coordinate transformation module carries out synchronous rotating coordinate transformation on the three-phase power grid voltage signal containing the positive sequence component and the negative sequence component to obtain a voltage component under a two-phase rotating coordinate system;
(3) the delay sampling period filtering module respectively delays one sampling period and two sampling periods for voltage components under a synchronous rotating coordinate system to quickly extract direct current components and double-frequency alternating current components, namely positive sequence voltage components and negative sequence voltage components of the power grid voltage;
(4) the amplitude and phase calculation module respectively calculates the real-time amplitude and phase of the power grid voltage according to the direct-current component and the double-frequency alternating-current component voltage component under the two-phase rotating coordinate system;
(5) the synchronous rotation coordinate inverse transformation module transforms direct-current component and double-frequency alternating-current component voltage signals under a two-phase rotation coordinate system into positive and negative sequence component signals of three-phase power grid voltage.
2. The method of claim 1, wherein the method further comprises the steps of: in the step (3), the voltage components in the synchronous rotating coordinate system are respectively delayed by TsAnd 2TsWherein said T issIs a sampling period;
the calculation formula of the k-th sampling of the direct current component under the synchronous rotating coordinate system is as follows:
the calculation formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotating coordinate system is as follows:
3. the method according to claim 2, wherein the method further comprises the steps of: in the step (3), the delay sampling period filtering module comprises a delay module and a delay sampling period filtering algorithm;
the time delay sampling period filtering algorithm is realized by enabling an original signal U on a synchronous rotating coordinate system to be synchronousd/qDelaying the signal U by one sampling periodd/q(t–Ts) Delaying signal U for two sampling periodsd/q(t–2Ts) Performing mathematical operation to obtain a direct current component and a double frequency alternating current component under a synchronous rotating coordinate system;
the direct current component k-th sampling time under the synchronous rotating coordinate system has the structural formula as follows:
wherein x isdRepresenting the d-axis component, xqRepresenting a q-axis component;
the structural formula of the k-th sampling of the double-frequency alternating current component under the synchronous rotating coordinate system is as follows:
4. the method of claim 1, wherein the method further comprises the steps of: in the step (4), the positive sequence component phase calculation formula of the three-phase grid voltage is as follows:
wherein, thetaexIndicating a judgment condition phase;
adding a judgment condition phase to ensure that the obtained phase is between 0 and 2 pi, wherein the judgment condition is as follows:
the calculation formula of the voltage component amplitudes of the positive sequence and the negative sequence of the three-phase power grid voltage is as follows:
5. the method of claim 1, wherein the method further comprises the steps of: in the step (5), the synchronous rotating coordinate inverse transformation module transforms the direct current component and the double-frequency alternating current component voltage signals under the two-phase rotating coordinate system into positive and negative sequence component signals of the three-phase power grid voltage, wherein the transformation formula is
Synchronous rotation inverse transformation matrix as Tdq/abc(ω t) wherein,
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Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101487861A (en) * | 2009-02-27 | 2009-07-22 | 国网电力科学研究院 | Detection method for electric voltage phase angle jump at network voltage dip |
| US20130322123A1 (en) * | 2012-05-31 | 2013-12-05 | Delta Electronics, Inc. | Control device and control method during bypassing of power units |
| US9048726B1 (en) * | 2013-03-11 | 2015-06-02 | The Boeing Company | Power system having repetitive control in symmetric sequences with harmonics cancellation |
| CN104836460A (en) * | 2015-06-04 | 2015-08-12 | 湖南大学 | Positive- and negative-sequence combined control method for three-phase PWM current transformer when power grid is imbalanced |
| CN105021872A (en) * | 2015-07-02 | 2015-11-04 | 北京国电通网络技术有限公司 | Active and passive component detection method for different current components in distorted and asymmetric voltage state of electrical network |
| CN105610178A (en) * | 2016-01-22 | 2016-05-25 | 广东志成冠军集团有限公司 | Unbalanced load control method and control system of three-phase half-bridge inverter |
| CN107045082A (en) * | 2017-06-12 | 2017-08-15 | 南京工程学院 | The synchronized phase open loop detection method of high accuracy and anti-noise jamming |
| CN107093954A (en) * | 2017-05-26 | 2017-08-25 | 电子科技大学 | The two-stage type three-phase four-arm inversion system and control strategy boosted with BOOST |
| CN108020731A (en) * | 2017-11-21 | 2018-05-11 | 浙江日风电气股份有限公司 | Positive-negative sequence extracting method |
| CN108761222A (en) * | 2018-05-21 | 2018-11-06 | 南京工程学院 | It is a kind of imbalance operating mode under network voltage order components quick extraction system and method |
| CN109582918A (en) * | 2018-11-16 | 2019-04-05 | 国网江苏省电力有限公司盐城供电分公司 | A kind of distribution voltage detecting algorithm |
| CN110308326A (en) * | 2019-07-15 | 2019-10-08 | 国网山西省电力公司电力科学研究院 | A method of open loop can be improved and surveys phase algorithm noiseproof feature |
| CN111122952A (en) * | 2019-12-12 | 2020-05-08 | 电子科技大学 | Method for rapidly detecting three-phase voltage sag |
-
2020
- 2020-06-18 CN CN202010562964.0A patent/CN111521858A/en active Pending
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101487861A (en) * | 2009-02-27 | 2009-07-22 | 国网电力科学研究院 | Detection method for electric voltage phase angle jump at network voltage dip |
| US20130322123A1 (en) * | 2012-05-31 | 2013-12-05 | Delta Electronics, Inc. | Control device and control method during bypassing of power units |
| US9048726B1 (en) * | 2013-03-11 | 2015-06-02 | The Boeing Company | Power system having repetitive control in symmetric sequences with harmonics cancellation |
| CN104836460A (en) * | 2015-06-04 | 2015-08-12 | 湖南大学 | Positive- and negative-sequence combined control method for three-phase PWM current transformer when power grid is imbalanced |
| CN105021872A (en) * | 2015-07-02 | 2015-11-04 | 北京国电通网络技术有限公司 | Active and passive component detection method for different current components in distorted and asymmetric voltage state of electrical network |
| CN105610178A (en) * | 2016-01-22 | 2016-05-25 | 广东志成冠军集团有限公司 | Unbalanced load control method and control system of three-phase half-bridge inverter |
| CN107093954A (en) * | 2017-05-26 | 2017-08-25 | 电子科技大学 | The two-stage type three-phase four-arm inversion system and control strategy boosted with BOOST |
| CN107045082A (en) * | 2017-06-12 | 2017-08-15 | 南京工程学院 | The synchronized phase open loop detection method of high accuracy and anti-noise jamming |
| CN108020731A (en) * | 2017-11-21 | 2018-05-11 | 浙江日风电气股份有限公司 | Positive-negative sequence extracting method |
| CN108761222A (en) * | 2018-05-21 | 2018-11-06 | 南京工程学院 | It is a kind of imbalance operating mode under network voltage order components quick extraction system and method |
| CN109582918A (en) * | 2018-11-16 | 2019-04-05 | 国网江苏省电力有限公司盐城供电分公司 | A kind of distribution voltage detecting algorithm |
| CN110308326A (en) * | 2019-07-15 | 2019-10-08 | 国网山西省电力公司电力科学研究院 | A method of open loop can be improved and surveys phase algorithm noiseproof feature |
| CN111122952A (en) * | 2019-12-12 | 2020-05-08 | 电子科技大学 | Method for rapidly detecting three-phase voltage sag |
Non-Patent Citations (6)
| Title |
|---|
| TIANQU HAO等: "Fast Symmetrical Component Extraction From Unbalanced Three-Phase Signals Using Non-Nominal dq -Transformation", 《IEEE TRANSACTIONS ON POWER ELECTRONICS》 * |
| 张臣: "MMC型柔性直流电网动态特性分析", 《中国优秀博硕士学位论文全文数据库(硕士)工程科技Ⅱ辑》 * |
| 彭诚等: "一种改进的三相不平衡电压暂降检测算法", 《电测与仪表》 * |
| 熊连松等: "不平衡工况下电网电压序分量快速提取方法", 《电力系统自动化》 * |
| 郝捷等: "基于可变采样周期滤波算法的电网电压序分量快速提取方法", 《电测与仪表》 * |
| 陈东明等: "基于改进滤波及正负序分离法的锁相环", 《电网技术》 * |
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