CN113866628B - Switch state analysis method based on current and voltage double-phase sequence comparison - Google Patents
Switch state analysis method based on current and voltage double-phase sequence comparison Download PDFInfo
- Publication number
- CN113866628B CN113866628B CN202111398561.8A CN202111398561A CN113866628B CN 113866628 B CN113866628 B CN 113866628B CN 202111398561 A CN202111398561 A CN 202111398561A CN 113866628 B CN113866628 B CN 113866628B
- Authority
- CN
- China
- Prior art keywords
- current
- voltage
- switch
- graph
- harmonic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000004458 analytical method Methods 0.000 title claims abstract description 17
- 238000000819 phase cycle Methods 0.000 title claims abstract description 15
- 230000000737 periodic effect Effects 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 8
- 230000008878 coupling Effects 0.000 claims description 3
- 238000010168 coupling process Methods 0.000 claims description 3
- 238000005859 coupling reaction Methods 0.000 claims description 3
- 230000009466 transformation Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention provides a switch state analysis method based on current and voltage double-phase sequence comparison, 1) detecting current and voltage on upper and lower side lines of a switch subjected to double-phase sequence comparison by using a current meter and a voltage meter, and carrying out harmonic analysis; 2) According to the formulas of fundamental wave sinusoidal current and fundamental wave sinusoidal voltage, five points are respectively taken in each period on the obtained fundamental wave current graph and the obtained fundamental wave voltage graph through the formulas of periodic signals; 3) Connecting five points in each period on the fundamental wave current graph and the fundamental wave voltage graph, and changing the current and voltage harmonic graph into current and voltage triangular waves; 4) And a fixed direct current component is coupled on the triangular wave graph, and the time sequences of the direct current component, the current and voltage crossing values are identical, namely the points on the corresponding lines at the upper end and the lower end of the same switch. The power states of the upper side and the lower side of the switch are determined through comparison of the current and the voltage double-phase sequences, so that the method is simple and feasible, the occurrence of the phenomenon of line burnout is effectively reduced, and the cost consumption is reduced.
Description
Technical Field
The invention relates to the technical field of transformer switches, in particular to a switch state analysis method based on current and voltage double-phase sequence comparison.
Background
The requirements on the reliability of electricity consumption are relatively improved, uninterrupted and reliable power distribution live working is ensured, the stable development of various enterprises in China is promoted, the importance of the power distribution live working is highlighted, and the improvement of the reliability of power supply is a particularly important and difficult task. When live working is carried out, one section of power supply needs to be disconnected, and because a user supplies power, a load (a generator or other power supplies) is added to one end of the disconnected power supply, and at the moment, the upper end and the lower end of a switch between the generator and the load are required to be consistent, and the switch synchronization of an external power supply for live working is required.
Disclosure of Invention
In order to solve the technical problems of the background technology, the invention provides a switch state analysis method based on current and voltage double-phase sequence comparison, which is simple and feasible, effectively reduces the occurrence of line burning phenomenon and reduces the cost consumption by determining the power states of the upper side and the lower side of a switch through the current and voltage double-phase sequence comparison.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
a switch switching state analysis method based on current and voltage double phase sequence comparison comprises the following steps:
1) Detecting current and voltage on the upper and lower side lines of the switch which are compared with each other by using a current meter and a voltmeter, and carrying out harmonic analysis;
2) According to the formulas of fundamental wave sinusoidal current and fundamental wave sinusoidal voltage, five points are respectively taken in each period on the obtained fundamental wave current graph and the obtained fundamental wave voltage graph through the formulas of periodic signals;
3) Connecting five points in each period on the fundamental wave current graph and the fundamental wave voltage graph, and changing the current and voltage harmonic graph into current and voltage triangular waves;
4) And a fixed direct current component is coupled on the triangular wave graph, and the time sequences of the direct current component, the current and voltage crossing values are identical, namely the points on the corresponding lines at the upper end and the lower end of the same switch.
Further, the harmonic analysis in the step 1) specifically includes:
setting: the three phases of harmonic current at the upper end of the switch are respectively I A 、I B 、I C The three phases of the harmonic voltage at the upper end of the switch are U respectively A 、U B 、U C The three phases of the harmonic current at the lower end of the switch are respectively I a 、I b 、I c The three phases of the harmonic voltage at the lower end of the switch are U respectively a 、U b 、U c ，；
A periodic current is decomposed by fourier transformation into a linear superposition of a direct current component I0 and sinusoidal currents of different frequencies:m is the number of Fourier times, ω is the angular frequency; the three-phase harmonic current at the upper end of the switch and the three-phase harmonic current at the lower end of the switch are converted by using the formula;
similarly, a periodic voltage is decomposed by fourier transform into a linear superposition of a dc component U0 and a sinusoidal voltage of different frequencies:m is the Fourier frequency, ω is the angular frequency, and the three-phase harmonic voltages at the upper end of the switch and the three-phase harmonic voltages at the lower end of the switch are transformed by the formula.
Further, the five points in the step 2) are respectively:
the fundamental current is (0, 0), (pi/2, I) 1 )，(0，π)，(3π/2，-I 1 ),(2π，0)；
The fundamental voltage is (0, 0), (pi/2, U) 1 )，(0，π)，(3π/2，-U 1 ),(2π，0)。
Further, the step 4) of coupling a fixed direct current component to the triangular wave pattern specifically includes:
in the obtained current triangle wave image, i=i is taken 1 2 and i= -I 1 2, counting the intersection points of the current triangular wave image and the two straight lines;
in the obtained voltage triangle wave image, u=u is taken 1 2 and u= -U 1 2, counting the intersection points of the voltage triangular wave image and the two straight lines;
upper three-phase current I of switch A 、I B 、I C Three phases of harmonic current at the lower end of the switch are respectively I a 、I b 、I c Comparing the obtained intersection points, wherein the intersection points are identical, namely the points on the corresponding lines at the two ends of the same switch;
three-phase voltage U at upper end of switch A 、U B 、U C The three phases of the harmonic voltage at the lower end of the switch are U respectively a 、U b 、U c And comparing the obtained intersection points, wherein the intersection points are identical, namely the points on the corresponding lines at the two ends of the same switch.
Compared with the prior art, the invention has the beneficial effects that:
1) The invention determines the power supply states of the upper side and the lower side of the switch by comparing the current and the voltage double phase sequences, and is simple and effective;
2) The circuit burning phenomenon is effectively reduced, the cost consumption is reduced, the occurrence of fire is reduced, and the safety of lives and properties of people is ensured.
Drawings
FIG. 1 is a flow chart of a method for analyzing the switching state of a switch based on current and voltage double phase sequence comparison;
fig. 2 is a plot of the harmonic, triangular, fixed dc component of the voltage/current of an embodiment of the present invention.
In the figure: the 1-fundamental current/fundamental voltage curve 2-harmonic curve takes five points 3-DC component 4-current and voltage triangle 5-crossing values every cycle.
Detailed Description
The following detailed description of the embodiments of the invention is provided with reference to the accompanying drawings.
As shown in fig. 1-2, a switch switching state analysis method based on current and voltage double phase sequence comparison comprises the following steps:
1) Detecting current and voltage on the upper and lower side lines of the switch which are compared with each other by using a current meter and a voltmeter, and carrying out harmonic analysis 1;
2) According to the formulas of fundamental wave sinusoidal current and fundamental wave sinusoidal voltage through the formulas of periodic signals, five points 2 are respectively taken in each period on the obtained fundamental wave current graph and the fundamental wave current/fundamental wave voltage curve 1 of the fundamental wave voltage graph;
3) Five points 2 in each period on the wiring fundamental wave current diagram and the fundamental wave voltage diagram change the current and voltage harmonic diagram into current and voltage triangular wave 4;
4) A fixed direct current component 3 is graphically coupled to the triangular wave 4,
5) Judging: the direct current component 3 and the current and voltage crossing value 5 have the same time sequence, namely the points on the corresponding lines at the upper end and the lower end of the same switch.
The specific implementation process of the method is as follows:
the harmonic analysis of step 1) is specifically:
setting: the three phases of harmonic current at the upper end of the switch are respectively I A 、I B 、I C The three phases of the harmonic voltage at the upper end of the switch are U respectively A 、U B 、U C The three phases of the harmonic current at the lower end of the switch are respectively I a 、I b 、I c The three phases of the harmonic voltage at the lower end of the switch are U respectively a 、U b 、U c ，；
A periodic current is decomposed by fourier transformation into a linear superposition of a direct current component I0 and sinusoidal currents of different frequencies:m is the number of Fourier times, ω is the angular frequency, and t is the time; the three-phase harmonic current at the upper end of the switch and the three-phase harmonic current at the lower end of the switch are converted by using the formula;
similarly, a periodic voltage is decomposed into a DC component U0 and sinusoidal voltages of different frequencies by Fourier transformationIs a linear superposition of:m is the Fourier frequency, ω is the angular frequency, t is the time, and the three-phase harmonic voltages at the upper end of the switch and the three-phase harmonic voltages at the lower end of the switch are transformed by the formula.
The step 2) is specifically as follows:
from the formula of the periodic signal, we can know that the formula of the fundamental sine current is i=i 1 sin(ωt+φ 1 ) According to this formula we take five points 2 on the resulting fundamental current plot, which are:
the fundamental current is (0, 0), (pi/2, I) 1 )，(0，π)，(3π/2，-I 1 ),(2π，0)。
The formula of the fundamental sine voltage is u=u 1 sin(ωt+φ 1 ) According to this formula we take five points 2 on the resulting harmonic voltage plot, which are:
the fundamental voltage is (0, 0), (pi/2, U) 1 )，(0，π)，(3π/2，-U 1 ),(2π，0)。
In the embodiment of fig. 2, the fundamental current and fundamental voltage curve 1 are located at the same point.
The step 3) is specifically as follows:
referring to fig. 2, the current and voltage harmonic diagram is formed into triangular wave 4 of current and voltage by connecting five points 2 in each period above the fundamental wave current diagram and the fundamental wave voltage diagram.
The triangular wave pattern in the step 4) is coupled with a fixed direct current component 3 specifically as follows:
in the obtained current triangle wave 4 image, i=i is taken 1 2 and i= -I 1 2, counting the intersection points of the current triangular wave image and the two straight lines;
in the obtained voltage triangle wave 4 image, u=u is taken 1 2 and u= -U 1 2, counting the intersection points of the voltage triangular wave image and the two straight lines;
in the embodiment of fig. 2, the two straight lines of the dc component 3 in the triangle wave 4 pattern of the current and voltage are identical in position.
Step 5) judging:
and (3) performing the operation on the voltages of all the measured points in the experiment, and comparing the obtained intersection points (the intersection value 5), wherein the intersection points are identical, namely the points on the two end lines of the same switch.
Upper three-phase current I of switch A 、I B 、I C Three phases of harmonic current at the lower end of the switch are respectively I a 、I b 、I c Comparing the obtained intersection points (5) and obtaining the same intersection point which is the point on the corresponding line of the two ends of the same switch;
three-phase voltage U at upper end of switch A 、U B 、U C The three phases of the harmonic voltage at the lower end of the switch are U respectively a 、U b 、U c And comparing the obtained intersection points (the intersection value 5), wherein the intersection points are identical, namely the points on the corresponding lines at the two ends of the same switch.
Comprehensive analysis
The analysis of the current and the voltage are combined, and only the pattern of the points on the two lines of the same switch is the pattern of the points on the two lines of the same switch. The method for analyzing the switching state of the switch by comparing the current and voltage double phase sequences effectively reduces the occurrence of the phenomenon of line burning, reduces the cost consumption, simultaneously reduces the occurrence of fire and ensures the safety of lives and properties of people.
The above examples are implemented on the premise of the technical scheme of the present invention, and detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the above examples. The methods used in the above examples are conventional methods unless otherwise specified.
Claims (2)
1. The switching state analysis method based on the comparison of the current and voltage double phase sequences is characterized by comprising the following steps:
1) Detecting current and voltage on the upper and lower side lines of the switch which are compared with each other by using a current meter and a voltmeter, and carrying out harmonic analysis;
2) According to the formulas of fundamental wave sinusoidal current and fundamental wave sinusoidal voltage, five points are respectively taken in each period on the obtained fundamental wave current graph and the obtained fundamental wave voltage graph through the formulas of periodic signals;
3) Connecting five points in each period on the fundamental wave current graph and the fundamental wave voltage graph, and changing the current and voltage harmonic graph into current and voltage triangular waves;
4) Coupling a fixed direct current component on the triangular wave graph, wherein the time sequences of the direct current component, the current and voltage crossing values are identical, namely the points on the corresponding lines at the upper end and the lower end of the same switch;
the five points of the step 2) are respectively:
the fundamental current is (0, 0), (pi/2, I) 1 )，(0，π)，(3π/2，-I 1 ),(2π，0)；
The fundamental voltage is (0, 0), (pi/2, U) 1 )，(0，π)，(3π/2，-U 1 ),(2π，0)。
The step 4) of coupling a fixed direct current component on the triangular wave graph specifically comprises the following steps:
in the obtained current triangle wave image, i=i is taken 1 2 and i= -I 1 2, counting the intersection points of the current triangular wave image and the two straight lines;
in the obtained voltage triangle wave image, u=u is taken 1 2 and u= -U 1 And (2) counting the intersection points of the voltage triangular wave image and the two straight lines.
2. The method for analyzing the switch state based on the comparison of the current and the voltage double phase sequences according to claim 1, wherein the harmonic analysis in the step 1) is specifically as follows:
setting: the three phases of harmonic current at the upper end of the switch are respectively I A 、I B 、I C The three phases of the harmonic voltage at the upper end of the switch are U respectively A 、U B 、U C The three phases of the harmonic current at the lower end of the switch are respectively I a 、I b 、I c The three phases of the harmonic voltage at the lower end of the switch are U respectively a 、U b 、U c ，；
One or more ofThe periodic current is decomposed by fourier transformation into a linear superposition of a direct current component I0 and sinusoidal currents of different frequencies:m is the number of Fourier times, ω is the angular frequency; the three-phase harmonic current at the upper end of the switch and the three-phase harmonic current at the lower end of the switch are converted by using the formula;
similarly, a periodic voltage is decomposed by fourier transform into a linear superposition of a dc component U0 and a sinusoidal voltage of different frequencies:m is the Fourier frequency, ω is the angular frequency, and the three-phase harmonic voltages at the upper end of the switch and the three-phase harmonic voltages at the lower end of the switch are transformed by the formula.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111398561.8A CN113866628B (en) | 2021-11-19 | 2021-11-19 | Switch state analysis method based on current and voltage double-phase sequence comparison |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111398561.8A CN113866628B (en) | 2021-11-19 | 2021-11-19 | Switch state analysis method based on current and voltage double-phase sequence comparison |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113866628A CN113866628A (en) | 2021-12-31 |
| CN113866628B true CN113866628B (en) | 2023-12-19 |
Family
ID=78985163
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111398561.8A Active CN113866628B (en) | 2021-11-19 | 2021-11-19 | Switch state analysis method based on current and voltage double-phase sequence comparison |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113866628B (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0298675A (en) * | 1988-10-05 | 1990-04-11 | Kawasoo Tekuseru Kk | Phase checker |
| JPH03206974A (en) * | 1990-01-10 | 1991-09-10 | Tokyo Electric Power Co Inc:The | Method and apparatus for phase discrimination |
| US5298853A (en) * | 1992-12-18 | 1994-03-29 | Lubos Ryba | Electrical apparatus for detecting relationships in three phase AC networks |
| CN102361446A (en) * | 2011-10-27 | 2012-02-22 | 上海贝岭股份有限公司 | Triangular wave oscillating circuit |
| CN102590646A (en) * | 2012-02-15 | 2012-07-18 | 上海大学 | Method for detecting positive sequence, negative sequence and harmonic current based on phase sequence filter |
| CN109683030A (en) * | 2019-01-09 | 2019-04-26 | 江苏智臻能源科技有限公司 | A kind of terminal phase sequence automatic identifying method |
| CN110850166A (en) * | 2019-12-09 | 2020-02-28 | 国网辽宁省电力有限公司鞍山供电公司 | Portable harmonic detector and harmonic analysis method thereof |
| CN111884339A (en) * | 2020-07-24 | 2020-11-03 | 贵州电网有限责任公司 | Judgment method and system based on self-adaptive switch action |
| CN112285608A (en) * | 2020-11-20 | 2021-01-29 | 西安热工研究院有限公司 | High-frequency power supply full-bridge inverter circuit open-circuit fault method |
| CN113267685A (en) * | 2021-07-05 | 2021-08-17 | 珠海格力电器股份有限公司 | Phase sequence detection device and method and electrical equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101537682B1 (en) * | 2014-01-28 | 2015-07-22 | 엘에스산전 주식회사 | Three-phase wiring detection device and coincidence phase detection method |
-
2021
- 2021-11-19 CN CN202111398561.8A patent/CN113866628B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0298675A (en) * | 1988-10-05 | 1990-04-11 | Kawasoo Tekuseru Kk | Phase checker |
| JPH03206974A (en) * | 1990-01-10 | 1991-09-10 | Tokyo Electric Power Co Inc:The | Method and apparatus for phase discrimination |
| US5298853A (en) * | 1992-12-18 | 1994-03-29 | Lubos Ryba | Electrical apparatus for detecting relationships in three phase AC networks |
| CN102361446A (en) * | 2011-10-27 | 2012-02-22 | 上海贝岭股份有限公司 | Triangular wave oscillating circuit |
| CN102590646A (en) * | 2012-02-15 | 2012-07-18 | 上海大学 | Method for detecting positive sequence, negative sequence and harmonic current based on phase sequence filter |
| CN109683030A (en) * | 2019-01-09 | 2019-04-26 | 江苏智臻能源科技有限公司 | A kind of terminal phase sequence automatic identifying method |
| CN110850166A (en) * | 2019-12-09 | 2020-02-28 | 国网辽宁省电力有限公司鞍山供电公司 | Portable harmonic detector and harmonic analysis method thereof |
| CN111884339A (en) * | 2020-07-24 | 2020-11-03 | 贵州电网有限责任公司 | Judgment method and system based on self-adaptive switch action |
| CN112285608A (en) * | 2020-11-20 | 2021-01-29 | 西安热工研究院有限公司 | High-frequency power supply full-bridge inverter circuit open-circuit fault method |
| CN113267685A (en) * | 2021-07-05 | 2021-08-17 | 珠海格力电器股份有限公司 | Phase sequence detection device and method and electrical equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113866628A (en) | 2021-12-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhao et al. | Universal high-frequency-link characterization and practical fundamental-optimal strategy for dual-active-bridge DC-DC converter under PWM plus phase-shift control | |
| Liu et al. | A three-phase PLL algorithm based on signal reforming under distorted grid conditions | |
| CN103259251B (en) | A kind of transformer excitation flow recognition method based on weight mathematical morphology | |
| CN105099200A (en) | Alternating-current phasor analysis method and modeling method for phase-shifting control dual active bridge direct-current converters | |
| CN102445595B (en) | Real-time measuring method for time-varying power of electrical power system | |
| JP6059751B2 (en) | Phase calibration device | |
| Pang et al. | Multi-timescale-based fault section location in distribution networks | |
| CN113866628B (en) | Switch state analysis method based on current and voltage double-phase sequence comparison | |
| CN110601620A (en) | Phase sequence self-adaptive control system and method for three-phase full-control rectifier bridge trigger pulse | |
| JP2014139541A (en) | Quantity of electricity measuring apparatus and measuring method for quantity of electricity, monitoring device using device and method thereof, three phase circuit measuring device, electric power system step-out forecast device, active filter, and opening and closing pole phase control device | |
| CN103308821B (en) | Intermittent arcing ground-fault line selection method based on improved phase locked loop | |
| Xiu et al. | Voltage sag detection method based on dq transform and complex wavelet transform | |
| CN209148771U (en) | A kind of Measurement of Harmonics in Power System device based on synchronized sampling complete cycle | |
| CN203981796U (en) | The transmission line power frequency parameter test instrument that the anti-high induction voltage of electronic type disturbs | |
| Zhao et al. | A passive islanding detection method based on interharmonic impedance | |
| CN110389251A (en) | A kind of instantaneous voltage dq decomposition method for grid voltage sags detection | |
| CN206250776U (en) | A kind of commutation device | |
| CN110146780A (en) | Isolated neutral flexibility distribution network system ferromagnetic resonance method of discrimination | |
| CN111431171B (en) | Device and method for changing low-voltage uninterrupted power supply into two phases and three phases | |
| CN110389252B (en) | Alpha beta detection method for power grid voltage drop | |
| CN204008885U (en) | A kind of electronic type is with many back transmission lines of tower power frequency parameter test instrument | |
| Wang et al. | A new phase selection method for single-phase grounding faults in distribution networks with full compensation arc suppression technology | |
| CN203368041U (en) | Device in on-line detection self-excitation type MCR for performing excitation control on state of thyristor | |
| CN102820654B (en) | Cooperative control method of power electronic system | |
| Liu et al. | Fault detection and location of microgrid based on distributed decision |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |