CN114089027A - Electric energy quality monitoring system and method - Google Patents
Electric energy quality monitoring system and method Download PDFInfo
- Publication number
- CN114089027A CN114089027A CN202111275659.4A CN202111275659A CN114089027A CN 114089027 A CN114089027 A CN 114089027A CN 202111275659 A CN202111275659 A CN 202111275659A CN 114089027 A CN114089027 A CN 114089027A
- Authority
- CN
- China
- Prior art keywords
- power quality
- module
- voltage
- monitoring
- phase voltage
- 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.)
- Pending
Links
- 238000012544 monitoring process Methods 0.000 title claims abstract description 142
- 238000000034 method Methods 0.000 title claims abstract description 36
- 238000007405 data analysis Methods 0.000 claims abstract description 25
- 230000005540 biological transmission Effects 0.000 claims abstract description 22
- 238000013441 quality evaluation Methods 0.000 claims abstract description 11
- 238000004458 analytical method Methods 0.000 claims description 27
- 238000001514 detection method Methods 0.000 claims description 11
- 230000009466 transformation Effects 0.000 claims description 7
- 230000008569 process Effects 0.000 abstract description 4
- 238000004364 calculation method Methods 0.000 description 12
- 239000013598 vector Substances 0.000 description 11
- 239000000463 material Substances 0.000 description 5
- 239000000284 extract Substances 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 238000000819 phase cycle Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R22/00—Arrangements for measuring time integral of electric power or current, e.g. electricity meters
- G01R22/06—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
- G01R22/061—Details of electronic electricity meters
- G01R22/063—Details of electronic electricity meters related to remote communication
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Remote Monitoring And Control Of Power-Distribution Networks (AREA)
Abstract
The invention discloses a power quality monitoring system and a method, comprising a data acquisition module, a data transmission module, a power quality monitoring module, an alarm module and a remote user query module; the data acquisition module is used for acquiring three-phase voltage signals of each monitoring node in real time and transmitting the acquired three-phase voltage signals to the electric energy quality monitoring module through the data transmission module; the power quality monitoring module comprises a data analysis module and a power quality evaluation module; the data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain the power quality indexes of the three-phase voltage signals; the power quality evaluation module determines the power quality grade of each monitoring node according to the power quality index; and the remote user query module is used for querying the electric energy quality index and the electric energy quality grade stored in the electric energy quality monitoring module. The monitoring of the power quality is realized, manual intervention is not needed in the whole process, and the monitoring efficiency of the power quality is improved.
Description
Technical Field
The invention relates to the technical field of power equipment monitoring, in particular to a power quality monitoring system and method.
Background
With the development of social economy, the power supply load of a power grid is increasing day by day, for the safe operation of the power grid and the guarantee of the requirements of residents and industrial power utilization, the power quality problem is more and more concerned by the society, and accidents caused by serious power quality problems occur occasionally, so that the loss of manpower, material resources and financial resources is caused, and therefore, the rapid, accurate and real-time safety monitoring on the power quality is very important.
At present, for the monitoring of the power quality, the staff mainly carries the power detection equipment to go to the power supply site to detect, and the power quality is determined according to the detection result, and because the terminal to be detected is more, part of the terminal to be detected is distributed in the area with bad conditions, and the position distribution is also more complicated, detects extravagant a large amount of manpower and materials on the spot, is difficult to satisfy the real-time demand of actual system business, and the transmission timeliness of the power quality monitoring system is directly influenced, resulting in the monitoring efficiency of the power quality to be low.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a power quality monitoring system and a power quality monitoring method, which solve the technical problem of low power quality monitoring efficiency in the prior art and achieve the technical effect of improving the power quality monitoring efficiency.
In a first aspect, the present disclosure provides an electric energy quality monitoring system:
a power quality monitoring system comprising: the device comprises a data acquisition module, a data transmission module, an electric energy quality monitoring module, an alarm module and a remote user query module.
The data acquisition module is used for acquiring three-phase voltage signals of each monitoring node in real time and transmitting the acquired three-phase voltage signals to the electric energy quality monitoring module through the data transmission module;
the power quality monitoring module comprises a data analysis module and a power quality evaluation module, and the data analysis module is used for analyzing the three-phase voltage signals of each monitoring node to obtain power quality indexes of the three-phase voltage signals; the power quality evaluation module is used for determining the power quality grade of each monitoring node according to the power quality index;
the remote user query module is used for querying the electric energy quality indexes and the electric energy quality grades of all monitoring nodes stored in the electric energy quality monitoring module.
According to a further technical scheme, the electric energy quality index comprises: voltage harmonic amplitude, three-phase unbalance and sag voltage characteristic quantity.
According to a further technical scheme, the power quality monitoring module further comprises a transmission detection module, the transmission detection module is used for monitoring data transmitted in the data transmission module, if the data are not transmitted successfully within a specified time or the data are transmitted in a specified time and are lost, data alarm information is generated, and an alarm is given through the alarm module.
According to the further technical scheme, the data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain voltage harmonic amplitude, and the method comprises the following steps:
performing voltage harmonic analysis on the three-phase voltage signals based on fast Fourier transform to obtain real part voltage amplitude values and imaginary part voltage amplitude values of the three-phase voltage signals;
and calculating to obtain a voltage harmonic amplitude according to the real part voltage amplitude and the imaginary part voltage amplitude.
Further technical scheme, the data analysis module analysis each monitoring node's three-phase voltage signal obtains three-phase unbalance degree, includes:
determining a positive sequence component and a negative sequence component of the three-phase voltage signal based on a symmetric component method;
and calculating to obtain the three-phase unbalance according to the positive sequence component and the negative sequence component.
The further technical scheme is that the method for determining the positive sequence component and the negative sequence component of the three-phase voltage signal based on the symmetrical component method comprises the following steps:
respectively determining the voltage vector of each phase of the three-phase voltage signal based on a symmetrical component method to obtain a plurality of voltage vectors;
and calculating to obtain a positive sequence component and a negative sequence component according to the plurality of voltage vectors.
Further technical scheme, data analysis module analysis each monitoring node's three-phase voltage signal obtains the sag voltage characteristic quantity, includes:
analyzing the three-phase voltage based on a voltage dq coordinate transformation analysis method to obtain a first voltage component of a d axis and a second voltage component of a q axis;
and calculating the sag voltage characteristic quantity according to the first voltage component and the second voltage component.
According to a further technical scheme, the step-down voltage characteristic quantity is obtained through calculation according to the first voltage component and the second voltage component, and the step-down voltage characteristic quantity comprises the following steps:
determining the amplitude variation of each phase of the three-phase voltage according to the first voltage component and the second voltage component;
and determining the phase jump of each phase of the three-phase voltage according to the first voltage component and the second voltage component.
According to the further technical scheme, the method for determining the power quality grade of each monitoring node comprises the following steps:
and comparing the received power quality index with a pre-stored standard power quality index range to determine the power quality grade of each monitoring node.
According to the further technical scheme, when any index in the electric energy quality indexes of the monitoring node exceeds the range of the prestored standard electric energy quality indexes, the monitoring node is indicated to have a fault, the alarm module gives an alarm, and the electric energy quality monitoring module retrieves the voltage data of the monitoring node and sends the data to the remote client.
In a second aspect, the present disclosure provides a power quality monitoring method, including:
step S01: collecting three-phase voltage signals of each monitoring node in real time;
step S02: analyzing the three-phase voltage signals of each monitoring node to obtain the electric energy quality index of the three-phase voltage signals;
step S03: determining the power quality grade of each monitoring node according to the power quality index;
step S04: and inquiring the power quality index and the power quality grade of each monitoring node through the remote client.
According to a further technical scheme, the electric energy quality index comprises: voltage harmonic amplitude, three-phase unbalance and sag voltage characteristic quantity.
According to the further technical scheme, the method for determining the power quality grade of each monitoring node comprises the following steps:
and comparing the received power quality index with a pre-stored standard power quality index range to determine the power quality grade of each monitoring node.
A computer readable storage medium having stored therein a plurality of instructions adapted to be loaded by a processor of a terminal device and to implement a power quality monitoring system as described above.
A computer-readable storage medium characterized by: in which a plurality of instructions are stored, said instructions being adapted to be loaded by a processor of a terminal device and to execute a power quality monitoring system as described above.
The above one or more technical solutions have the following beneficial effects:
the invention provides a power quality monitoring system and a power quality monitoring method.
The invention provides a power quality monitoring system and a power quality monitoring method, which do not need manual intervention in the whole process, solve the technical problem of low power quality monitoring efficiency in the prior art and achieve the technical effect of improving the power quality monitoring efficiency.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.
Fig. 1 is a schematic structural diagram of a power quality monitoring system according to an embodiment of the present invention;
fig. 2 is a flowchart of a power quality monitoring method according to a second embodiment of the present invention.
Detailed Description
It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
With the continuous development of society, electric power plays an increasingly important role in various industries, but with the continuous expansion of electric power application range, the phenomenon of electric power pollution is increasingly serious. The direct result of the power pollution is the reduction of the power quality, which can cause great damage to both the power supplier and the power consumer, such as affecting the use quality of the alternating current by the user, and even damaging the electric equipment. At present, the monitoring of the power quality is mainly carried out by a worker to carry a power detection device to a power supply site, the power quality is determined according to a detection result, a large amount of manpower and material resources are wasted due to manual field detection, the real-time service requirement of an actual system is difficult to meet, the transmission timeliness of a power quality monitoring system is directly influenced, and the monitoring efficiency of the current power quality is low.
Therefore, the embodiment of the application provides an electric energy quality monitoring system and method, a three-phase voltage signal of each monitoring node is collected in real time, the three-phase voltage signal is analyzed to obtain an electric energy quality index, the electric energy quality grade of each monitoring node is further determined, a worker inquires the electric energy quality information of each monitoring node through a remote client, the electric energy quality is monitored, waste of manpower and material resources is avoided, and the monitoring efficiency is improved.
Example one
The embodiment provides an electric energy quality monitoring system:
as shown in fig. 1, a power quality monitoring system includes: the system comprises a data acquisition module, a data transmission module, an electric energy quality monitoring module, an alarm module and a remote user query module;
the data acquisition module is used for acquiring three-phase voltage signals of each monitoring node in real time and transmitting the acquired three-phase voltage signals to the electric energy quality monitoring module through the data transmission module;
the power quality monitoring module comprises a data analysis module and a power quality evaluation module;
the data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain the power quality indexes of the three-phase voltage signals;
the power quality evaluation module determines the power quality grade of each monitoring node according to the power quality index;
the remote user query module is used for querying the electric energy quality indexes and the electric energy quality grades of all monitoring nodes stored in the electric energy quality monitoring module.
In this embodiment, the data acquisition module can be any kind of voltage signal collection equipment, and it is installed at each monitoring node, gathers the voltage signal of each monitoring node, three-phase voltage signal promptly, through communication equipment, for example GSM communication module etc. with this three-phase voltage signal transmission to the electric energy quality monitoring module in high in the clouds, electric energy quality monitoring module receives this three-phase voltage signal, can acquire the three-phase voltage signal who obtains this three phase current. It is noted that the three-phase voltage signals include an a-phase voltage signal, a B-phase voltage signal, and a C-phase voltage signal.
The system also comprises a transmission detection module, wherein in the data transmission process, the transmission detection module monitors the data transmitted to the power quality monitoring module by the data acquisition module, if the data is not transmitted successfully within the specified time, such as the transmission line is damaged, or the data is transmitted successfully within the specified time but the transmission data is lost, namely the transmission data is incomplete, data alarm information is generated, and the alarm module gives an alarm.
The data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain electric energy quality indexes of the three-phase voltage signals, wherein the electric energy quality indexes comprise voltage harmonic amplitude, three-phase unbalance and sag voltage characteristic quantities.
Specifically, the specific process of analyzing the three-phase voltage signal by the data analysis module includes:
the data analysis module stores a voltage harmonic analysis model in advance, such as a fourier model, a fast fourier model, and the like, which can perform harmonic analysis. And after receiving the three-phase voltage signals, the data analysis module inputs the three-phase voltage signals to an internally stored voltage harmonic analysis model, and the voltage harmonic analysis model performs waveform analysis on the three-phase voltage signals and extracts harmonics. The harmonic wave refers to a series of component waves with frequencies higher than the fundamental frequency in the periodic non-sinusoidal wave in the power supply system, except for the component wave with the same frequency as the fundamental frequency, and is collectively referred to as a harmonic wave. The control equipment obtains the harmonic wave based on the voltage harmonic wave analysis model, and extracts the amplitude of the harmonic wave, namely the voltage harmonic wave amplitude can be obtained.
In this embodiment, the data analysis module performs voltage harmonic analysis on the three-phase voltage signal based on fast fourier transform to obtain a real part voltage amplitude and an imaginary part voltage amplitude of the three-phase voltage signal.
The data analysis module is pre-stored with a fast Fourier transform algorithm, and carries out waveform analysis on the three-phase voltage signal based on the fast Fourier transform algorithm, extracts real part voltages and imaginary part voltages of all harmonics in the three-phase voltage signal, and stores the real part voltages and the imaginary part voltages.
After the data analysis module obtains the real part voltage and the imaginary part voltage of all the harmonics in the three-phase voltage signal, the voltage harmonic amplitude of the K-th harmonic can be obtained through calculation according to the following formula (1):
in the above formula, UkThe voltage harmonic amplitude of the kth harmonic,
is the real part voltage of the kth harmonic,
the imaginary voltage of the kth harmonic.
And similarly, the voltage harmonic amplitudes of other harmonics in the three-phase voltage signal are obtained through calculation according to the formula.
The method and the device for evaluating the power quality of the power system have the advantages that the real part voltage and the imaginary part voltage of each harmonic are obtained through extraction based on fast Fourier transform, then the voltage harmonic amplitude of each harmonic can be obtained through simple square root calculation, the calculation is simple, and the evaluation efficiency of the method for evaluating the power quality provided by the embodiment of the application can be greatly improved. Meanwhile, the calculation of the embodiment of the application is simple, the calculation amount is small, the requirement on the calculation capacity of the control equipment is low, common equipment with a data processing function can meet the requirement, and the cost of the control equipment can be effectively reduced.
The data analysis module is prestored with an unbalance degree analysis model, receives three-phase voltage signals, inputs the three-phase voltage signals to the unbalance degree analysis model, calculates the unbalance degree of the three-phase voltage signals through the unbalance degree analysis model, outputs the unbalance degree of the three-phase voltage signals, and can obtain the three-phase unbalance degree of the three-phase voltage signals. The three-phase unbalance degree is used for representing the three-phase voltage unbalance degree of the three-phase voltage signal.
First, positive and negative sequence components of the three-phase voltage signals are determined based on a symmetric component method.
For asymmetric three-phase voltage, the fundamental frequency component of the three-phase voltage is asymmetric, a symmetric component algorithm is stored in the control equipment in advance, and the obtained three-phase voltage signal is decomposed into three-phase symmetric components through the symmetric component algorithm: one set is the positive sequence component, indicated by the subscript "1", the phase sequence is identical to the phase sequence of the original asymmetric sinusoid, i.e. the order of a-B-C, the phases being 120 degrees apart. One set is the negative sequence component, indicated by the subscript "2", and the phase sequence is opposite to the original sinusoid, i.e., A-C-B, and the phases are also 120 degrees apart. The other set is the zero sequence component, denoted by the subscript "0", and the phases of the three phases are the same.
And secondly, calculating according to the positive sequence component and the negative sequence component to obtain the three-phase unbalance.
After obtaining the zero sequence component, the positive sequence component and the negative sequence component of the three-phase voltage signal, calculating the three-phase unbalance of the three-phase voltage signal according to the following formula (2):
in the above formula, ε represents a three-phase unbalance degree, U'1Is a positive sequence component, U'2Is the negative sequence component.
The method comprises the steps of determining a positive sequence component and a negative sequence component of a three-phase voltage signal based on a symmetrical component method, and calculating to obtain the three-phase unbalance degree according to the positive sequence component and the negative sequence component.
The above numbers respectively determine the positive sequence component and the negative sequence component of the three-phase voltage signal based on a symmetrical component method, including: the data analysis module is stored with a symmetrical component algorithm, and voltage vectors of each phase in three-phase voltage are analyzed and extracted based on the algorithm to obtain a plurality of voltage vectors, namely voltage vectors of A phase, B phase and C phase;
and calculating to obtain a positive sequence component and a negative sequence component according to the plurality of voltage vectors.
After a plurality of voltage vectors of the three-phase voltage signal are obtained through calculation, the zero sequence component, the positive sequence component and the negative sequence component of the three-phase voltage signal are obtained through calculation according to the following formula (3):
in the above formula, U'0Is zero sequence component, U'1Is a positive sequence component, U'2Is a negative sequence component, U'AIs an A phase voltage vector, U'BIs a B-phase voltage vector, U'CThe C-phase voltage vector is denoted by α, which is a rotation factor, and the rotation factor is specifically set according to actual conditions, and this embodiment is not limited in any way.
The data analysis module is pre-stored with a voltage sag analysis model, receives three-phase voltage signals, inputs the three-phase voltage signals to the voltage sag analysis model, and analyzes the voltage sag characteristics of the three-phase voltage signals through the voltage sag analysis model, so that the sag voltage characteristic quantity can be obtained. The sag voltage characteristic quantity is used for representing the voltage change degree of the three-phase voltage signal under the preset sag condition.
In this embodiment, first, the three-phase voltages are analyzed based on a voltage dq coordinate transformation analysis method, and a first voltage component of the d-axis and a second voltage component of the q-axis are obtained.
The voltage sag characteristic quantity is a short-time voltage variation characteristic value with the duration of 0.5 cycle to 1min, wherein the voltage effective value is reduced to 0.1-0.9 pu under the power frequency condition. The sag voltage characteristic quantities include, but are not limited to, two kinds: and voltage sag and phase jump, wherein the control equipment converts the three-phase voltage into a coordinate point in a dq coordinate based on a voltage dq coordinate transformation analysis method, and directly extracts a first voltage component of a d axis and a second voltage component of a q axis in the coordinate.
And secondly, calculating to obtain the sag voltage characteristic quantity according to the first voltage component and the second voltage component.
If the sag voltage characteristic quantity includes two types, namely voltage sag and phase jump, the relationship among the first voltage component, the second voltage component, the voltage sag and the phase jump is as shown in the following formula (4) and formula (5):
(4) in formulae (5) and (5), UdαA first voltage component of d-axis, UqαA second voltage component of q-axis, UsagIs the voltage sag amplitude and alpha is the phase jump angle.
Specifically, the first voltage component U of the d-axis is extracted through the above stepsdαAnd a second voltage component U of the q-axisqαAnd then:
determining the amplitude variation of each phase of the three-phase voltage according to the first voltage component and the second voltage component:
in the above formula, UdαA first voltage component of d-axis, UqαA second voltage component of q-axis, UsagIs the voltage sag magnitude.
The data analysis module determines phase jump of each phase of the three-phase voltage according to the first voltage component and the second voltage component:
according to the method and the device, the three-phase voltage signals are analyzed through a voltage dq coordinate transformation analysis method, finally, the characteristic quantity of voltage sag, such as voltage sag and phase jump, is obtained through calculation, the voltage dq coordinate transformation analysis method is mature, the calculation is simple, and the evaluation efficiency and the evaluation stability of the power quality evaluation method provided by the embodiment of the application can be greatly improved.
After the three-phase voltage signals of each monitoring node are processed to obtain the voltage harmonic amplitude, the three-phase unbalance degree and the sag voltage characteristic quantity of the three-phase voltage signals, the electric energy quality evaluation module determines the electric energy quality grade of each monitoring node according to the electric energy quality index.
Specifically, the power quality evaluation module compares the received power quality index with a pre-stored standard power quality index range to determine the power quality level of each monitoring node.
The pre-stored standard electric energy quality index range is set manually and is formulated according to the national standard of electric energy quality, and the monitored electric energy quality index is closer to the standard value and the electric energy quality grade is higher.
When any index in the electric energy quality indexes of the monitoring node exceeds the range of the prestored standard electric energy quality indexes, the monitoring node is indicated to have a fault, the alarm module gives an alarm, and the electric energy quality monitoring module calls the voltage data of the monitoring node and sends the data to the remote client.
The remote user query module provides a remote query function for workers, the workers send data query requests through the remote client, and the cloud server receives the requests and then calls real-time voltage signals, electric energy quality indexes and electric energy quality grades of monitoring nodes stored in the electric energy quality monitoring module.
The utility model provides a pair of power quality monitoring system, through the three-phase voltage signal of each monitoring node of real-time acquisition, carry out the analysis to this three-phase voltage signal and obtain the power quality index, and then confirm the power quality grade of each monitoring node, the staff passes through the power quality information of each monitoring node of remote client inquiry, realizes the monitoring to power quality, avoids the waste of manpower and materials, improves monitoring efficiency.
Example two
The embodiment provides a power quality monitoring method, which comprises the following steps:
as shown in fig. 2, a power quality monitoring method is implemented based on the above system. The method for monitoring the power quality provided by the embodiment comprises the following steps:
step S01: collecting three-phase voltage signals of each monitoring node in real time;
step S02: analyzing the three-phase voltage signals of each monitoring node to obtain the electric energy quality index of the three-phase voltage signals;
step S03: determining the power quality grade of each monitoring node according to the power quality index;
step S04: and inquiring the power quality index and the power quality grade of each monitoring node through the remote client.
In this embodiment, in the step S02, the power quality indicator includes a voltage harmonic amplitude, a three-phase imbalance degree, and a sag voltage characteristic quantity.
In step S02, analyzing the three-phase voltage signals of each monitoring node to obtain a voltage harmonic amplitude, including:
performing voltage harmonic analysis on the three-phase voltage signals based on fast Fourier transform to obtain real part voltage amplitude values and imaginary part voltage amplitude values of the three-phase voltage signals;
and calculating to obtain a voltage harmonic amplitude according to the real part voltage amplitude and the imaginary part voltage amplitude.
In step S02, analyzing the three-phase voltage signals of each monitoring node to obtain three-phase imbalance, including:
determining a positive sequence component and a negative sequence component of the three-phase voltage signal based on a symmetric component method;
and calculating to obtain the three-phase unbalance according to the positive sequence component and the negative sequence component.
In step S02, analyzing the three-phase voltage signals of each monitoring node to obtain a sag voltage characteristic quantity, including:
analyzing the three-phase voltage based on a voltage dq coordinate transformation analysis method to obtain a first voltage component of a d axis and a second voltage component of a q axis;
and calculating the sag voltage characteristic quantity according to the first voltage component and the second voltage component.
In step S03, determining the power quality level of each monitoring node according to the power quality index includes:
and comparing the received power quality index with a pre-stored standard power quality index range to determine the power quality grade of each monitoring node.
The specific working process of the system is implemented in the manner of the first embodiment, and is not described herein again.
Those skilled in the art will appreciate that the modules or steps of the present invention described above can be implemented using general purpose computer means, or alternatively, they can be implemented using program code that is executable by computing means, such that they are stored in memory means for execution by the computing means, or they are separately fabricated into individual integrated circuit modules, or multiple modules or steps of them are fabricated into a single integrated circuit module. The present invention is not limited to any specific combination of hardware and software.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.
Claims (10)
1. An electric energy quality monitoring system, characterized by, includes: the system comprises a data acquisition module, a data transmission module, an electric energy quality monitoring module, an alarm module and a remote user query module;
the data acquisition module is used for acquiring three-phase voltage signals of each monitoring node in real time and transmitting the acquired three-phase voltage signals to the electric energy quality monitoring module through the data transmission module;
the power quality monitoring module comprises a data analysis module and a power quality evaluation module; the data analysis module is used for analyzing the three-phase voltage signals of each monitoring node to obtain the electric energy quality indexes of the three-phase voltage signals; the power quality evaluation module is used for determining the power quality grade of each monitoring node according to the power quality index;
the remote user query module is used for querying the electric energy quality indexes and the electric energy quality grades of all monitoring nodes stored in the electric energy quality monitoring module.
2. A power quality monitoring system according to claim 1 wherein said power quality indicators comprise: voltage harmonic amplitude, three-phase unbalance and sag voltage characteristic quantity.
3. The power quality monitoring system according to claim 1, wherein the system further comprises a transmission detection module, the transmission detection module is configured to monitor the data transmitted in the data transmission module, and if the data is not successfully transmitted within a specified time or the data is missing within the specified time, generate a data alarm message and alarm through the alarm module.
4. The power quality monitoring system of claim 2, wherein the data analysis module analyzes the three-phase voltage signals at each monitoring node to obtain voltage harmonic amplitudes, and comprises:
performing voltage harmonic analysis on the three-phase voltage signals based on fast Fourier transform to obtain real part voltage amplitude values and imaginary part voltage amplitude values of the three-phase voltage signals;
and calculating to obtain a voltage harmonic amplitude according to the real part voltage amplitude and the imaginary part voltage amplitude.
5. The power quality monitoring system of claim 2, wherein the data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain three-phase imbalance, and comprises:
determining a positive sequence component and a negative sequence component of the three-phase voltage signal based on a symmetric component method;
and calculating to obtain the three-phase unbalance according to the positive sequence component and the negative sequence component.
6. The power quality monitoring system according to claim 2, wherein the data analysis module analyzes the three-phase voltage signals of each monitoring node to obtain the sag voltage characteristic quantity, and comprises:
analyzing the three-phase voltage based on a voltage dq coordinate transformation analysis method to obtain a first voltage component of a d axis and a second voltage component of a q axis;
and calculating the sag voltage characteristic quantity according to the first voltage component and the second voltage component.
7. The power quality monitoring system of claim 1 wherein determining the power quality level of each monitoring node based on the power quality indicator comprises:
and comparing the received power quality index with a pre-stored standard power quality index range to determine the power quality grade of each monitoring node.
8. The power quality monitoring system according to claim 7, wherein when any one of the power quality indexes of the monitoring node exceeds a pre-stored standard power quality index range, it indicates that the monitoring node has a fault, the alarm module gives an alarm, and the power quality monitoring module retrieves the voltage data of the monitoring node and sends the data to the remote client.
9. A power quality monitoring method is characterized by comprising the following steps:
step S01: collecting three-phase voltage signals of each monitoring node in real time;
step S02: analyzing the three-phase voltage signals of each monitoring node to obtain the electric energy quality index of the three-phase voltage signals;
step S03: determining the power quality grade of each monitoring node according to the power quality index;
step S04: and inquiring the power quality index and the power quality grade of each monitoring node through the remote client.
10. The power quality monitoring method according to claim 9, wherein the power quality indicators include: voltage harmonic amplitude, three-phase unbalance and sag voltage characteristic quantity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111275659.4A CN114089027A (en) | 2021-10-29 | 2021-10-29 | Electric energy quality monitoring system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111275659.4A CN114089027A (en) | 2021-10-29 | 2021-10-29 | Electric energy quality monitoring system and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114089027A true CN114089027A (en) | 2022-02-25 |
Family
ID=80298297
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111275659.4A Pending CN114089027A (en) | 2021-10-29 | 2021-10-29 | Electric energy quality monitoring system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114089027A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013057416A1 (en) * | 2011-10-19 | 2013-04-25 | Schneider Electric Industries Sas | Method and device for analysing the quality of the electrical energy in a three-phase electric network |
| CN103454530A (en) * | 2013-09-03 | 2013-12-18 | 苏州太谷电力股份有限公司 | Detection device and detection method for power quality |
| CN105301416A (en) * | 2015-11-30 | 2016-02-03 | 曾正扬 | Electric energy quality monitoring device and monitoring method thereof |
| CN112698133A (en) * | 2020-12-14 | 2021-04-23 | 国网上海市电力公司 | Voltage quality comprehensive evaluation method based on big data |
| CN112782503A (en) * | 2020-12-24 | 2021-05-11 | 深圳供电局有限公司 | Power quality evaluation method and device, control equipment and storage medium |
-
2021
- 2021-10-29 CN CN202111275659.4A patent/CN114089027A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013057416A1 (en) * | 2011-10-19 | 2013-04-25 | Schneider Electric Industries Sas | Method and device for analysing the quality of the electrical energy in a three-phase electric network |
| CN103454530A (en) * | 2013-09-03 | 2013-12-18 | 苏州太谷电力股份有限公司 | Detection device and detection method for power quality |
| CN105301416A (en) * | 2015-11-30 | 2016-02-03 | 曾正扬 | Electric energy quality monitoring device and monitoring method thereof |
| CN112698133A (en) * | 2020-12-14 | 2021-04-23 | 国网上海市电力公司 | Voltage quality comprehensive evaluation method based on big data |
| CN112782503A (en) * | 2020-12-24 | 2021-05-11 | 深圳供电局有限公司 | Power quality evaluation method and device, control equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103439613A (en) | Electric power security integrated monitoring device and analyzing method thereof | |
| CN108074198B (en) | Power system PMU bad data identification method | |
| CN115327445B (en) | Abnormal judgment method and system for grounding current of converter transformer iron core and clamping piece | |
| CN113285471A (en) | Method, device and equipment for sensing and positioning sub-supersynchronous oscillation source of offshore wind power plant | |
| CN113484596A (en) | Power quality monitoring method, device and equipment and readable storage medium | |
| CN107797023A (en) | Imbalance of three-phase voltage source localization method, device and system | |
| Li et al. | Research on new characteristics of power quality in distribution network | |
| CN113376456A (en) | Cloud platform-based method for analyzing and managing electric quantity and electric charge of large electric power user | |
| CN114089027A (en) | Electric energy quality monitoring system and method | |
| CN202066925U (en) | Harmonic monitor of electric network | |
| CN107181460B (en) | A kind of photovoltaic system method for detecting arc | |
| Wang et al. | Implementation of state-wide power quality monitoring and analysis system in China | |
| CN103219724B (en) | A kind of intelligent grid multi objective control system and method | |
| CN104850751A (en) | Current quality assessment method | |
| Nadhiroh et al. | Real-time monitoring of power quality for web based electrical power panel using LabVIEW | |
| CN104849548A (en) | Instantaneous frequency monitoring method and system for electric power system | |
| CN113990057B (en) | Broadband oscillation station terminal early warning method, system, storage medium and server | |
| CN115632410A (en) | Broadband oscillation protection method for new energy power system | |
| CN110231541B (en) | Method for carrying out inverse calculation on equivalent electrical parameters of system based on online monitoring of damped oscillation waves | |
| CN108092272A (en) | A kind of voltage stabilization on-line monitoring method based on the Kalman filtering that fades | |
| CN110417111B (en) | Power quality detection method | |
| Gao et al. | Harmonic source identification method based on sinusoidal approximation | |
| Yang et al. | Power quality evaluation method for multi-power quality problem in distribution network | |
| CN109842110B (en) | Low-voltage analysis algorithm for power distribution terminal of low-voltage transformer area | |
| Jiang et al. | Power Analysis Based on Non-intrusive Power Load Monitoring and Decomposition |
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 |