WO2023207124A1

WO2023207124A1 - Power grid oscillation source distributed positioning method and system, device, storage medium, computer program, and computer program product

Info

Publication number: WO2023207124A1
Application number: PCT/CN2022/138043
Authority: WO
Inventors: 吴艳平; 赵国庆; 张海东; 姚志强; 樊陈; 窦仁晖; 任浩; 任辉; 杨青; 姜玉磊
Original assignee: 中国电力科学研究院有限公司; 国网江苏省电力有限公司电力科学研究院; 国家电网有限公司
Priority date: 2022-04-25
Filing date: 2022-12-09
Publication date: 2023-11-02
Also published as: CN114865653A

Abstract

Disclosed in the present invention are a power grid low-frequency and wide-frequency oscillation source distributed positioning method and system, a device, a storage medium, a computer program, and a computer program product. The method comprises: collecting synchronous phasor data and harmonic and inter-harmonic phasor data of each branch in a transformer substation, a power plant, and a new energy pooling station; apparatuses in stations using the synchronous phasor data to calculate a low-frequency oscillation source positioning characteristic quantity, and using the harmonic and inter-harmonic phasor data to calculate a wide-frequency oscillation source positioning characteristic quantity; and uploading the low-frequency oscillation source positioning characteristic quantity and the wide-frequency oscillation source positioning characteristic quantity for power grid wide-area oscillation source positioning.

Description

Distributed positioning method and system of power grid oscillation sources, equipment, storage media, computer program, computer program products

Cross-application of related applications

This disclosed embodiment is based on a Chinese patent application with application number 202210458998.4, application date is April 25, 2022, and the application name is "Power Grid Oscillation Source Distributed Positioning Method, System, Equipment and Storage Medium", and requires the Chinese patent Priority of the application, the entire content of this Chinese patent application is hereby incorporated by reference into this disclosure.

Technical field

The present disclosure relates to but is not limited to the field of power system automation, and in particular, to a distributed positioning method and system of power grid oscillation sources, equipment, storage media, computer programs, and computer program products.

Background technique

With the large-scale application of new energy technology and AC and DC transmission technology, the proportion of power electronic equipment in the power grid continues to increase, injecting a large number of harmonics and inter-harmonics, and interacting with the power grid to form high frequency signals ranging from several hertz (Hz) to thousands. Hz oscillation phenomenon, the oscillation form has expanded from the original low-frequency oscillation dominated by electromechanical transients to a more complex broadband oscillation. Oscillation seriously affects the safe and stable operation of the power system. How to quickly and accurately locate the oscillation source is an important issue in power grid operation control and a long-term research hotspot in the academic community.

With the acceleration of the construction of new power systems, measurement equipment such as broadband measurement devices and synchronized phasor measurement devices are more and more widely used for measurement and monitoring of the main network and distribution network of the power system. Massive amounts of data are processed centrally at the dispatching main station. Using synchronized phasor and harmonic and inter-harmonic phasor measurement data to identify oscillations and locate oscillation sources, there are problems such as high data storage and computing pressure, and difficulty in ensuring the real-time performance of oscillation monitoring and positioning.

Currently, synchronized phasor measurement devices and measurement and control devices installed at factories and stations (such as substations, power stations, and new energy collection stations) measure synchronized phasor data and harmonics such as fundamental voltage, current amplitude, phase angle, and power. , interharmonic and oscillation power phasor data, and monitor low-frequency oscillation and broadband oscillation events in real time. At present, the oscillation source positioning function is implemented centrally through main stations such as Wide Area Measurement System (WAMS), which mainly includes the positioning of low-frequency oscillation sources related to electromechanical transients. The positioning algorithm is mainly based on synchronized phasor transient energy. Streaming algorithm. However, the application of broadband oscillation source positioning is still in its infancy, and the source is mainly traced through the size and phase characteristics of the dominant components of harmonics and interharmonics.

Contents of the invention

In view of the problems and difficulties existing in the centralized monitoring and positioning of low-frequency oscillations and broadband oscillations at the main station, this disclosure proposes a distributed positioning method and system, equipment, storage media, computer programs, and computer program products for power grid oscillation sources, which can be used in substations and power plants and new energy collection stations and other measurement data sources. Each branch is used as a unit to calculate the characteristic quantities required for monitoring and positioning of low-frequency oscillation and broadband oscillation in real time, and the analysis results are sent to the main station to reduce the processing pressure of the main station. Achieve quick positioning of low-frequency and broadband oscillation sources.

In order to achieve the above objectives, the embodiments of the present disclosure adopt the following technical solutions to achieve:

A distributed positioning method of power grid oscillation sources, applied to the plant and station side, including:

Collect synchronized phasor, harmonic and inter-harmonic phasor data based on bus and branch units;

Triggered by plant station oscillation monitoring alarms or commands issued by the master station, synchronized phasors are used to calculate the location characteristics of low-frequency oscillation sources on-site, and harmonic and inter-harmonic phasor data are used to calculate the location characteristics of broadband oscillation sources;

The low-frequency oscillation source positioning characteristic quantity and the broadband oscillation source positioning characteristic quantity are sent to the main station for distributed positioning of power grid oscillation sources.

In some embodiments of the present disclosure, calculating the low-frequency oscillation source positioning characteristic quantity using synchronized phasor data includes:

The criterion for the plant station to trigger the low-frequency _oscillation alarm is: within the set _number of _oscillations

After the low-frequency oscillation alarm is triggered or the master station command is received, the plant station device uses the collected synchronized phasor data to start the transient energy integration calculation for the bus and branch units; when the low-frequency oscillation alarm is eliminated or the set integration time is reached T _{max_int} , the device ends the transient energy flow integral calculation;

The plant and station device uses the bus branch as a unit and uses the integration start time as the origin to perform transient energy integration curve fitting calculations and output the low-frequency oscillation characteristic quantity of each bus i branch j. The low-frequency oscillation characteristic quantity is the fitting slope k _ij and intercept b _ij .

In some embodiments of the present disclosure, the fundamental wave active power P _base is calculated as:

In formula (1), U _a , I _a , U _b , I _b , U _c , and I _c are voltage and current synchronized phasors;

The plant and station devices use synchronized phasor data to calculate the transient energy integral of each bus i branch j. The method is:

or

In formula (2), T _{max_int} is the set integration time, E _dis is the transient energy integral, ΔP _ij =P _{base_ij} -P _{ave_ij} , and P _{ave_ij} is the current average value of the fundamental wave power of branch j of bus i.

In some embodiments of the present disclosure, after the low-frequency oscillation alarm is triggered or the plant station device receives a master station command, if the low-frequency oscillation alarm is not eliminated, the transient energy integration duration T _{max_int} is reached, and the fitting slope k _ij and When the intercept b _ij is, take the current time as T ₀ and re-execute the transient energy integration and fitting according to the integration time T _{max_int} in a loop until the low-frequency oscillation alarm is eliminated.

In some embodiments of the present disclosure, the distributed positioning of power grid oscillation sources refers to the low-frequency oscillation source positioning based on the power grid topology and the fitting parameters k _ij and b _ij of each branch's transient energy integral curve sent from the plant and station. position.

In some embodiments of the present disclosure, the use of harmonic and inter-harmonic phasor data to calculate the broadband oscillation source positioning characteristic quantity includes:

The plant and station device calculates the instantaneous active power sampling sequence based on the voltage and current sampling values u _a , _ia , u _b , _ib , _uc , _ic , and uses the Fast Fourier Transform (FFT) algorithm according to Equation (3) Extract the dominant oscillation power component, the amplitude P _fk and frequency f _k of the oscillation power component;

{P _f1 ...P _fn }=FFT{u _a i _a +u _b i _b +u _c i _c } (3);

The factory station device takes the bus branch as a unit. Within the set time T _sso , the factory station device detects that the amplitude of any wide-band oscillation power component P _fk continuously exceeds the set alarm setting value P _sso , triggering a wide-band oscillation alarm.

In some embodiments of the present disclosure, after the broadband oscillation alarm is triggered, the factory station device tracks the n oscillation power components with the largest amplitude according to the set frequency deviation f _offset in each calculation cycle. When the oscillation power component frequency f _k is different from the previous When the deviation of the measured oscillation frequency f _lastk satisfies equation (4), it is judged to be the same oscillation power component, f _lastk is updated to f _k , and the tracking of f _k is performed in the next period;

f _lastk -f _offset ＜f _k ＜f _lastk +f _offset (4);

In some embodiments, according to the frequency f _k of the oscillation power component P _fk and the fundamental frequency f _base , the harmonic or interharmonic phasors of the phase voltage and current are matched, such as Equation (5); the voltage and current phases are obtained by matching. Quantity: U _Xfk- , I _Xfk- , U _Xfk+ , I _Xfk+ ; the subscript

f _base -f _k -f _offset <f _YX <f _base -f _k +f _offset or f _base +f _k -f _offset <f _YX <f _base +f _k +f _offset (5).

In some embodiments of the present _disclosure _, the plant and station device calculates the active power _P

P _{fk_r} =P _{Afk_r} +P _{Bfk_r} +P _{Cfk_r} (7);

Calculate the accumulated energy according to the set number of cycles N

When E _Nfk ≤E _set- , the amplitude of the oscillation power component P _fk of the bus i branch j is marked as negative. When E _Nfk ≥ E _set+ , the amplitude of the oscillation power component P _fk is marked as positive.

The amplitude of the oscillation power after the mark is transmitted to the master station: a characteristic quantity for positioning the broadband oscillation source.

In some embodiments of the present disclosure, the distributed positioning of power grid oscillation sources means that the plant station device calculates the amplitude and sign of each branch and each oscillation power component, and the main station calculates the broadband oscillation source sent by the substation according to the The positioning feature quantity locates the oscillation source within the network.

A distributed positioning device for power grid oscillation sources, applied at the factory and station ends, including:

The acquisition module is configured to collect synchronized phasor, harmonic and inter-harmonic phasor data based on bus and branch units;

The calculation module is configured to use synchronized phasors to calculate the location characteristics of low-frequency oscillation sources on-site when triggered by plant station oscillation monitoring alarms or commands issued by the master station, and use harmonic and inter-harmonic phasor data to calculate the location characteristics of broadband oscillation sources. quantity;

The uploading module is configured to send the low-frequency oscillation source positioning characteristic quantity and the broadband oscillation source positioning characteristic quantity to the main station for distributed positioning of power grid oscillation sources by the main station.

A distributed positioning device for power grid oscillation sources, applied to the main station, including:

The issuing module is configured to issue distributed positioning start commands for power grid oscillation sources;

The receiving module is configured to receive the oscillation source positioning characteristic quantity sent from the factory station;

A positioning module configured to perform distributed positioning of power grid oscillation sources based on low-frequency oscillation source positioning characteristic quantities or broadband oscillation source positioning characteristic quantities.

A distributed positioning system for power grid oscillation sources, including:

The factory station adopts the power grid oscillation source distributed positioning device, configured to collect synchronized phasor data, harmonic and inter-harmonic phasor data, and oscillation power components, and starts based on local oscillation monitoring alarms or commands issued by the master station Calculation of low-frequency oscillation source characteristic quantities and broadband oscillation source characteristic quantities;

The master station, the power grid oscillation source distributed positioning device, is configured to issue a power grid oscillation source distributed positioning start command to the factory station; receive and perform low-frequency or broadband power grid operation based on the oscillation source characteristic quantity sent by the factory station. Oscillation source location.

An electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the distributed positioning method of power grid oscillation sources. A step of.

A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the power grid oscillation source distributed positioning method are implemented.

Embodiments of the present disclosure provide a computer program that includes computer readable code. When the computer readable code is read and executed by a computer, part of the method in any embodiment of the present disclosure is implemented or All steps.

Embodiments of the present disclosure provide a computer program product. The computer program product includes a non-transitory computer-readable storage medium storing a computer program. When the computer program is read and executed by a computer, any embodiment of the present disclosure is implemented. some or all of the steps in the method.

Compared with the existing technology, the embodiments of the present disclosure have the following beneficial effects:

In view of the low-frequency and broadband oscillation problems that may occur in the grid-connected operation of conventional power supplies and distributed new energy sources under the background of power system development, the disclosed embodiments propose a distributed oscillation source positioning method based on substations, power stations and new energy stations. This method Low-frequency and broadband oscillation monitoring and traceability characteristic calculations can be performed on all accessed lines and equipment branches at the installation site of measurement or communication devices. The calculation results are sent to main stations such as dispatching to support distributed positioning of power grid oscillation sources. The disclosed embodiments can improve the real-time and comprehensiveness of power grid oscillation monitoring and positioning, and reduce the data storage, calculation and processing pressure of the main station.

Description of drawings

Figure 1 is a schematic diagram of the architecture of the oscillation source distributed positioning system proposed in the disclosed embodiment;

Figure 2 is a schematic diagram of the calculation process of the distributed positioning characteristic quantity of the oscillation source proposed in the disclosed embodiment;

Figure 3 is a block diagram 1 of a power grid oscillation source distributed positioning system proposed by an embodiment of the present disclosure;

Figure 4 is a block diagram 2 of a power grid oscillation source distributed positioning system proposed by an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of an electronic device according to an embodiment of the present disclosure.

Detailed ways

In order to enable those skilled in the art to better understand the embodiments of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described implementation The examples are only examples of a part of the disclosure, but not all of the examples. Based on the embodiments in this disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of protection of this disclosure.

It should be noted that the terms "first", "second", etc. in the description and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances so that the embodiments of the disclosure described herein can be practiced in sequences other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, e.g., a process, method, system, product, or apparatus that encompasses a series of steps or units and need not be limited to those explicitly listed. Those steps or elements may instead include other steps or elements not expressly listed or inherent to the process, method, product or apparatus.

As shown in Figure 1, the first purpose of the embodiment of the present disclosure is to provide a distributed positioning method of power grid oscillation sources, which is applied to the factory side, including:

Collect synchronized phasor, harmonic and inter-harmonic phasor data in busbars and branches at substations, power plants, new energy stations and other plants;

The plant and station device uses synchronized phasors to calculate the positioning characteristics of low-frequency oscillation sources on-site, and uses harmonic and inter-harmonic phasor data to calculate the positioning characteristics of wide-band oscillation sources;

The calculation and transmission of oscillation source positioning characteristic quantities are triggered by factory station oscillation monitoring alarms or commands issued by the master station;

The factory station sends the low-frequency oscillation source positioning characteristic quantity and the broadband oscillation source positioning characteristic quantity to the dispatching and other main stations for positioning of wide-area oscillation sources in the power grid.

As shown in Figure 1, the distributed positioning method of power grid oscillation sources may include: dispatching 101 and other master stations, dispatching data network 102, first plant station 103, Nth plant station 104, etc. Master stations such as the dispatching 101 can be used to realize oscillation source positioning, and factory stations such as the first factory station 103 and the Nth factory station 104 can realize oscillation monitoring and calculation of oscillation source characteristic quantities. The dispatch data network 102 can realize the interaction between the main station and the factory station, such as the issuance of networking trigger commands and the uploading of oscillation source characteristic quantity results. The first factory station 103 may include a broadband processing unit 1031 for communication, a data concentrator 1032, a communication gateway 1033, a broadband measurement device 1034 for measurement, a synchronized phasor measurement device 1035, a measurement and control device 1036, and support Current transformer (CT)/voltage transformer (Potential transformer, PT) or acquisition unit 1037, etc. The Nth factory station 104 may include a broadband processing unit 1041 for communication, a data concentrator 1042, a communication gateway 1043, a broadband measurement device 1044 for measurement, a synchronized phasor measurement device 1045, a measurement and control device 1046, and support CT/PT or acquisition unit 1047, etc.

Embodiments of the present disclosure also provide a distributed positioning method for power grid oscillation sources, which is applied to the main station, including:

The master station issues distributed positioning commands for power grid oscillation sources triggered by the network;

The main station receives the oscillation source characteristic quantity sent from the factory station. The oscillation source characteristic quantity is calculated by the factory station. The method is:

Distributed positioning of power grid oscillation sources is carried out based on the positioning characteristics of low-frequency oscillation sources or the positioning characteristics of broadband oscillation sources.

Among them, embodiments of the present disclosure propose a distributed positioning method of power grid oscillation sources, including low-frequency oscillation of 0.1 to 2.5 Hz and wide-band oscillation of frequencies above 2.5 Hz.

The principle of the embodiment of the present disclosure is to calculate the low-frequency oscillation sources respectively at the factory and station based on the synchronized phasors and harmonic and inter-harmonic voltages and current phasors measured by devices such as broadband measuring devices, synchronized phasor measuring devices or measurement and control devices. , broadband oscillation source positioning characteristic quantity, and the calculation results are sent to the main station such as transmission dispatching to realize distributed positioning of power grid oscillation sources.

Embodiments of the present disclosure can perform feature quantity calculations for low-frequency and broadband oscillation source positioning on synchronized phasor, harmonic and inter-harmonic phasor data in-situ at substations, power stations and new energy sites, and then use the calculation results to It is sent to the main station such as dispatching to realize the analysis and positioning of power grid oscillation sources, thereby improving the real-time and comprehensiveness of power grid oscillation monitoring and positioning, and reducing the data processing pressure of the main station.

As shown in Figures 1 and 2, the steps for calculating the positioning characteristics of low-frequency oscillation sources and broadband oscillation sources are explained below:

Taking the calculation of low-frequency oscillation source positioning characteristic quantities as an example, it includes:

Step 1: Monitor the low-frequency oscillation in real time according to the alarm setting value P _osc , and monitor the wide-band oscillation in real time according to the alarm setting value P _sso ; within the set number of oscillations X _osc , the average peak-to-valley difference of the fundamental wave active power P _base fluctuation exceeds the alarm setting value In the case of P _osc , a low-frequency oscillation alarm signal is triggered;

Step 2: After the low-frequency oscillation alarm signal is triggered or the main station networking trigger signal is received, the plant-side measurement or communication device based on the collected and measured synchronized phasor data such as active power, reactive power, frequency and voltage, according to the branch Start the transient energy integral calculation. When the low-frequency oscillation alarm signal is eliminated or reaches the settable integration time T _{max_int} , the device ends the transient energy flow integral calculation.

Step 3: The plant-side device performs linear fitting calculation on the transient energy integral curve, and outputs the fitting slope k _ij and intercept b _ij of the transient energy integral curve of bus i branch j with the integration start time as the origin.

Step 4: The plant-side device writes the transient energy linear fitting parameter results into the communication protocol message with the master station, and the master station fits the parameters according to the power grid topology and the transient energy integral curve of each branch sent from the plant-station side. k _ij and b _ij perform low-frequency oscillation source positioning.

Step 5: When the plant-side measurement or communication device detects that the amplitude of the oscillation power component at any frequency f _k exceeds P _sso for the set time T _sso , a broadband oscillation alarm signal is triggered.

In plant-side measurement or communication devices such as substations, power stations, and new energy stations, based on synchronized phasor, harmonic and inter-harmonic phasor data, the characteristic quantities used to locate low-frequency and broadband oscillation sources are sent to The overall plan for oscillation source positioning by the master station.

The starting method and calculation period for collecting and calculating the characteristic quantities used for low-frequency oscillation source positioning at the factory station are started by the low-frequency oscillation alarm signal and the master station networking trigger signal respectively. The calculation period is a settable parameter, and finally the low-frequency oscillation alarm is eliminated. .

Taking the calculation of broadband oscillation source positioning characteristic quantities as an example, it includes:

Step 6: After the broadband oscillation alarm signal is triggered, the factory station device selects the n oscillation power components with the largest amplitude (n can be set), and tracks them according to the settable frequency deviation f _offset in each calculation cycle. When the oscillation power When the deviation between the frequency f _k of the component and the previously measured oscillation frequency f _lastk satisfies equation (4), it is judged to be the same oscillation power component, and f _lastk is set to f _k to track f _k in the next calculation cycle.

f _lastk -f _offset ＜f _k ＜f _lastk +f _offset (4);

Step 7: Match the harmonic or interharmonic phasor of the A, B, and C phase voltages and currents according to the oscillation power frequency f _k and the fundamental frequency f _base . When the frequency of the harmonic or interharmonic phasor satisfies the formula (5 ), the voltage and current phasors obtained by matching are recorded as U _Xfk- , I _Xfk- , U _Xfk+ , I _Xfk+ respectively. The generated active power _P ) Calculate the three-phase total active power P _{fk_r} generated on the branch by the oscillation frequency f _k .

f _base -f _k -f _offset <f _YX <f _base -f _k +f _offset or f _base +f _k -f _offset <f _YX <f _base +f _k +f _offset (5);

P _{fk_r} =P _{Afk_r} +P _{Bfk_r} +P _{Cfk_r} (7);

Step 8: Calculate the accumulated energy according to the settable N periods

When E _Nfk ≤E _set- , it is determined that the branch is the source of the energy of the oscillation power component P _fk ; when E _Nfk ≥ E _set+ , it is determined that the branch consumes the energy of the frequency oscillation power component P _fk . The absolute values of E _set- and E _set+ can be the same or different.

Step 9: The factory station marks the sign of the oscillation power of bus i branch j with frequency f _k . When E _Nfk ≤ E _set- , the mark is a negative number; when E _Nfk ≥ E _set+ , the sign is marked as a positive number; after the mark The measured value of the oscillation power is sent to the main station; the main station locates the oscillation source based on the sign and amplitude of the oscillation power at each frequency of each branch.

Among them, the criterion for iterative tracking and identification of the broadband oscillation power component is that the oscillation frequency of the power component is within the deviation range of the frequency value recorded in the previous calculation cycle. The deviation can be fixed or set.

The direction criterion of the broadband oscillation power component is determined by comparing the time accumulation of its associated voltage, current harmonics or inter-harmonic active power with the set value. If it is greater than the positive set value, it will be judged as positive, and if it is less than the negative set value, it will be judged as positive. The value is judged as negative.

The identification method of the wide-band oscillation power component is to mark the sign of the wide-band oscillation power component direction as the sign of the wide-band oscillation power component amplitude. The marked oscillation power component amplitude and frequency are transmitted to the Main site.

Step 10: The main station implements low-frequency oscillation source positioning and broadband oscillation source positioning respectively based on the sign and amplitude of each branch k _ij and b _ij sent from each factory station, and the amplitude of the oscillation power component.

As shown in Figure 2, the synchronized phasor 201 can include active power, reactive power, frequency and voltage, etc. The factory-side measurement or communication device can implement the calculation of the active power change 202, the frequency change calculation 203, and the reactive power change. Energy calculation 204, voltage amplitude change calculation 205, etc.; after the low-frequency oscillation alarm signal is triggered or the master station networking trigger signal 206 is received, the transient energy calculation 207 is started according to the branch. When the low-frequency oscillation alarm signal is eliminated or reaches a settable The integration time is , and the device ends the transient energy flow integral calculation; then, the plant-side device performs linear fitting calculation 208 on the transient energy integral curve. Harmonics and inter-harmonic phasors 209 can include voltage, current, oscillation power components, etc. Broadband power oscillation alarm 211 can be performed for the oscillation power component to achieve oscillation component frequency tracking 210; harmonics, Interharmonic phasor matching 212, and then perform active power accumulation calculation 213, so that the plant and station end can mark the oscillation power symbol identification 214; finally, the plant and station end can calculate the transient energy linear fitting parameter results and the oscillation power symbol identification. The results are uploaded to the main station to locate the oscillation source 215.

The disclosed embodiments are not limited by the structure and type of the measurement or communication device used, the communication protocol between the factory station and the master station, and the best embodiments for specific applications.

In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure more clear, the implementation examples of the present disclosure will be further described in detail below with reference to Figure 1 . Here, the illustrative embodiments of the present disclosure and their descriptions are used to explain the present invention, but are not used to limit the present disclosure.

Step 1: According to equation (1), the plant-side device calculates the fundamental active power P _base based on the voltage and current synchronized phasors U _a , I _a , U _b , I _b , U _c , and I _c , and sets the alarm value P _osc monitors low-frequency oscillations in real time. When the difference between adjacent peaks and valleys of the active power P _base exceeds _Posc and reaches or exceeds the set number of times X _osc , a low-frequency oscillation alarm signal is triggered.

Step 2: After the low-frequency oscillation alarm signal is triggered or the main station network is triggered, the plant-side device can be based on the measured synchronized phasor data such as active power, reactive power, frequency and voltage, according to Equation (2) or its simplification The formula starts the branch transient energy integral calculation. When the low-frequency oscillation alarm signal is eliminated or reaches the set integration time T _{max_int} , the device ends the transient energy flow integral E _dis calculation.

or

Step 3: The plant-side device performs a linear fitting calculation on the curve of the transient energy integral E _dis , and outputs the fitting slope k _ij and intercept of the transient energy integral curve of the bus i branch j with the integration starting time as the origin. _bij . Write k _ij and b _ij into the recommended national standard (GB/T26865.2) protocol message and send it to the main station.

Step 4: If the low-frequency oscillation alarm signal is not eliminated, set the previous integration end time to T ₀ and press T _{max_int} to execute (1) and (2) until the low-frequency oscillation alarm signal is eliminated.

Step 5: According to equation (3), the plant-side device calculates the instantaneous active power sampling sequence based on the voltage and current sampling values u _a , _ia , u _b , _ib , _uc , and _ic , and extracts the dominant 10 An oscillation power component, the amplitude P _fk and frequency f _k of the oscillation power component, k=1~10. The wide-band oscillation power components are monitored in real time one by one according to the alarm setting value P _sso . If the amplitude of the oscillation power component of any frequency f _k exceeds P _sso and reaches the set time T _sso , the wide-band oscillation alarm signal is triggered.

{P _f1 ...P _fn }=FFT{u _a i _a +u _b i _b +u _c i _c } (3);

(6) After the broadband oscillation alarm signal is triggered, the plant-side device selects the five oscillation power components with the largest amplitude; each calculation cycle tracks each oscillation power component according to the set frequency deviation f _offset = 2.5Hz. When the oscillation power frequency f The deviation of _k's previously measured oscillation frequency f _lastk satisfies equation (4), and is judged to be the same oscillation power component. f _lastk is set to f _k to track f _k in the next calculation period.

(7) According to f _k matching related A, B, C phase voltage, current harmonics and inter-harmonic phasors, the voltage and current phasors are obtained by matching according to the frequency deviation conditions shown in equation (5), which are recorded as U respectively. _Xfk- , _I _Xfk- , _U _Xfk+ , I _Xfk+ , calculate the single-phase active power P

(8) Take N=10 and calculate the accumulated energy E _Nfk . When E _Nfk ≤E _set- , it is judged that this branch is the source of oscillation energy with frequency P _fk ; when E _Nfk ≥E _set+ , it is judged that this branch consumes oscillation energy with frequency f _k . The absolute values of E _set- and E _set+ can be the same or different.

(9) The plant-side acquisition and measurement device marks the sign of the oscillation power component P _fk of bus i branch j. When E _Nfk ≤ E _set- , it is marked as a negative number; when E _Nfk ≥ E _set+ , it is marked as a positive number; the mark is The final oscillation power component measurement value is written into the GB/T26865.2 protocol message and sent to the master station;

(10) The main station realizes low-frequency oscillation source positioning and broadband oscillation source positioning respectively according to the branch k _ij , b _ij , the amplitude and sign of the oscillation power component P _fk sent from each factory station.

As shown in Figure 3, the embodiment of the present disclosure also provides a distributed positioning device for power grid oscillation sources, which is applied to factories and stations, including:

The acquisition module 301 is integrated in the factory station device to collect synchronized phasor data, harmonic and inter-harmonic phasor data;

The calculation module 302 is integrated in the factory station device, and calculates the positioning characteristic quantity of the low-frequency oscillation source based on the synchronized phasor data, and calculates the positioning characteristic quantity of the broadband oscillation source based on the harmonic and inter-harmonic phasor data and the broadband oscillation power component;

The uploading module 303 is integrated in the factory station device and uploads low-frequency oscillation source positioning characteristics and broadband oscillation source positioning characteristics for dispatching and other master stations to locate low-frequency and wide-band oscillation sources in the power grid.

In the calculation module, the use of synchronized phasor data to calculate low-frequency oscillation source positioning features specifically includes:

The calculation method of the fundamental wave active power P _base is:

The plant and station devices use synchronized phasor data to calculate the transient energy integral of each bus i branch j. The specific method is:

or

In the calculation module, the use of harmonic and inter-harmonic phasor data to calculate broadband oscillation source positioning characteristic quantities specifically includes:

The plant and station device calculates the instantaneous active power sampling sequence based on the voltage and current sampling values u _a , _ia , _ub , _ib , uc , _ic _, and extracts the dominant oscillation power component through the FFT algorithm according to Equation (3). The oscillation power The amplitude P _fk and frequency f _k of the component;

{P _f1 ...P _fn }=FFT{u _a i _a +u _b i _b +u _c i _c }(3);

After the wide-band oscillation alarm is triggered, the factory station device tracks the n oscillation power components with the largest amplitude according to the set frequency deviation f _offset in each calculation cycle. When the oscillation power component frequency f _k is equal to the previously measured oscillation frequency f _lastk When the deviation satisfies equation (4), it is judged to be the same oscillation power component, f _lastk is updated to f _k , and tracking of f _k is performed in the next period;

f _lastk -f _offset ＜f _k ＜f _lastk +f _offset (4);

_The plant and station devices calculate _the active power _P

P _{fk_r} =P _{Afk_r} +P _{Bfk_r} +P _{Cfk_r} (7);

Calculate the accumulated energy according to the set number of cycles N

When E _Nfk ≤E _set- , the amplitude of the oscillation power component P _fk of the bus i branch j is marked as negative; when E _Nfk ≥ E _set+ , the amplitude of the oscillation power component P _fk is marked as positive;

Among them, the distributed positioning of power grid oscillation sources means that the plant station device calculates the amplitude and sign of each branch and each oscillation power component, and the main station performs the positioning characteristics of the broadband oscillation source within the network based on the broadband oscillation source sent by the sub-station. The oscillation source is located.

As shown in Figure 4, an embodiment of the present disclosure also provides a distributed positioning device for power grid oscillation sources, including:

The issuing module 401 is integrated in the main station such as power grid dispatching and is configured to issue distributed positioning start commands for power grid oscillation sources;

The receiving module 402 is integrated in the main station such as power grid dispatching and is configured to receive the oscillation source positioning characteristic quantity sent from the factory station;

The positioning module 403 is integrated in a main station such as power grid dispatching and is configured to perform distributed positioning of power grid oscillation sources based on low-frequency oscillation source positioning characteristics or broadband oscillation source positioning characteristics.

The distributed positioning of power grid oscillation sources based on the positioning characteristics of low-frequency oscillation sources or the positioning characteristics of broadband oscillation sources specifically includes:

The specific calculation method of using synchronized phasors to calculate the positioning characteristics of low-frequency oscillation sources in situ and using harmonic and inter-harmonic phasor data to calculate the positioning characteristics of wide-band oscillation sources is as described in the above embodiments and will not be repeated here.

As shown in Figure 1, an embodiment of the present disclosure also provides a distributed positioning system for power grid oscillation sources, including:

The factory station adopts a distributed positioning device for power grid oscillation sources applied to the factory station. It is configured to collect synchronized phasor data, harmonic and inter-harmonic phasor data, and oscillation power components. Based on the local oscillation monitoring alarm or the main station issued The command starts the calculation of low-frequency oscillation source characteristic quantities and broadband oscillation source characteristic quantities;

The main station adopts a power grid oscillation source distributed positioning device applied to the main station, and is configured to issue a power grid oscillation source distributed positioning start command to the factory station; receive and perform power grid operation based on the oscillation source characteristic quantities sent by the factory station. Locating low-frequency or broadband oscillation sources.

As shown in Figure 5, an embodiment of the present disclosure provides an electronic device 500, including a memory 501, a processor 502, a communication interface 503, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the distributed positioning method of the power grid oscillation source are implemented.

The steps of the power grid oscillation source distributed positioning method adopt the above positioning method.

Embodiments of the present disclosure provide a computer-readable storage medium that stores a computer program. When the computer program is executed by a processor, the steps of the distributed positioning method for power grid oscillation sources are implemented.

A computer-readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device, and may be a volatile storage medium or a non-volatile storage medium. The computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), Erasable programmable read-only memory (flash memory), static random access memory, portable compact disk read-only memory, digital versatile disk, memory stick, floppy disk, mechanical encoding device, such as a punched card or recessed card with instructions stored on it The protruding structure in the groove, and any suitable combination of the above. As used herein, computer-readable storage media are not to be construed as transient signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or through electrical wires. transmitted electrical signals.

Embodiments of the present disclosure also provide a computer program. The computer program includes computer readable code. When the computer readable code is read and executed by a computer, part of the method in any embodiment of the present disclosure is implemented. or all steps.

Embodiments of the present disclosure also provide a computer program product, including computer readable code, or a non-volatile computer readable storage medium carrying the computer readable code. When the computer readable code is stored in a processor of an electronic device, When running, the processor in the electronic device executes part or all of the steps of the above method.

Those skilled in the art will appreciate that embodiments of the present disclosure may be provided as methods, systems, or computer program products. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media having computer-usable program code embodied therein. Available storage media for computers include, but are not limited to, disk storage, CD-ROM (Compact Disc Read-Only Memory, CD-ROM), optical storage, etc.

The disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a use A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure but not to limit it. Although the present disclosure has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that the present disclosure can still be modified. Modifications or equivalent substitutions may be made to the specific implementations, and any modifications or equivalent substitutions that do not depart from the spirit and scope of the disclosure shall be covered by the protection scope of the claims of this disclosure.

Claims

A distributed positioning method of power grid oscillation sources, applied to the plant and station side, including:

Collect synchronized phasor, harmonic and inter-harmonic phasor data based on bus and branch units;

Triggered by plant station oscillation monitoring alarms or commands issued by the master station, synchronized phasors are used to calculate the location characteristics of low-frequency oscillation sources on-site, and harmonic and inter-harmonic phasor data are used to calculate the location characteristics of broadband oscillation sources;

The low-frequency oscillation source positioning characteristic quantity and the broadband oscillation source positioning characteristic quantity are sent to the main station for distributed positioning of power grid oscillation sources.
The method of claim 1, wherein,

The use of synchronized phasor data to calculate low-frequency oscillation source positioning characteristics includes:

The criterion for the plant station to trigger the low-frequency oscillation alarm is: within the set number of oscillations

After the low-frequency oscillation alarm is triggered or the master station command is received, the plant station device uses the collected synchronized phasor data to start the transient energy integration calculation for the bus and branch units; when the low-frequency oscillation alarm is eliminated or the set integration time is reached T max_int , the device ends the transient energy flow integral calculation;

The plant and station device uses the bus branch as a unit and uses the integration start time as the origin to perform transient energy integration curve fitting calculations and output the low-frequency oscillation characteristic quantity of each bus i branch j. The low-frequency oscillation characteristic quantity is the fitting slope k ij and intercept b ij .
The method of claim 2, wherein

The calculation method of the fundamental wave active power P base is:

In formula (1), U a , I a , U b , I b , U c , and I c are voltage and current synchronized phasors;

The plant and station devices use synchronized phasor data to calculate the transient energy integral of each bus i branch j. The method is:

In formula (2), T max_int is the set integration time, E dis is the transient energy integral, ΔP ij =P base_ij -P ave_ij , and P ave_ij is the current average value of the fundamental wave power of branch j of bus i.
The method of claim 2, wherein

After the low-frequency oscillation alarm is triggered or the master station command is received by the plant station device, if the low-frequency oscillation alarm is not eliminated, the transient energy integration duration T max_int is reached, and the slope k ij and intercept b ij are obtained by fitting, the current time is is T 0 , re-execute the transient energy integration and fitting according to the integration time T max_int in a loop until the low-frequency oscillation alarm is eliminated.
The method of claim 2, wherein

The distributed positioning of power grid oscillation sources refers to the positioning of low-frequency oscillation sources based on the power grid topology and the fitting parameters k ij and b ij of each branch's transient energy integral curve sent from the plant and station.
The method of claim 1, wherein,

The use of harmonic and inter-harmonic phasor data to calculate broadband oscillation source positioning characteristic quantities includes:

The plant and station device calculates the instantaneous active power sampling sequence based on the voltage and current sampling values ua , ia , ub , ib , uc, ic , and extracts the dominant oscillation through the fast Fourier transform FFT algorithm according to Equation (3) Power component, the amplitude P fk and frequency f k of the oscillation power component;

{P f1 ...P fn }=FFT{u a i a +u b i b +u c i c } (3);

The factory station device takes the bus branch as a unit. Within the set time T sso , the factory station device detects that the amplitude of any wide-band oscillation power component P fk continuously exceeds the set alarm setting value P sso , triggering a wide-band oscillation alarm.
The method of claim 6, wherein

After the wide-band oscillation alarm is triggered, the factory station device tracks the n oscillation power components with the largest amplitude according to the set frequency deviation f offset in each calculation cycle. When the oscillation power component frequency f k is equal to the previously measured oscillation frequency f lastk When the deviation satisfies equation (4), it is judged to be the same oscillation power component, f lastk is updated to f k , and tracking of f k is performed in the next period;

f lastk -f offset ＜f k ＜f lastk +f offset (4);

In some embodiments, according to the frequency f k of the oscillation power component P fk and the fundamental frequency f base , the harmonic or interharmonic phasors of the phase voltage and current are matched, such as Equation (5); the voltage and current phases are obtained by matching. Quantity: U Xfk- , I Xfk- , U Xfk+ , I Xfk+ ; the subscript

f base -f k -f offset <f YX <f base -f k +f offset or f base +f k -f offset <f YX <f base +f k +f offset (5).
The method of claim 6, wherein

The plant and station devices calculate the active power P

P fk_r =P Afk_r +P Bfk_r +P Cfk_r (7);

Calculate the accumulated energy according to the set number of cycles N
When E Nfk ≤E set- , the amplitude of the oscillation power component P fk of the bus i branch j is marked as negative; when E Nfk ≥ E set+ , the amplitude of the oscillation power component P fk is marked as positive;

The amplitude of the oscillation power after the mark is transmitted to the master station: a characteristic quantity for positioning the broadband oscillation source.
The method of claim 6, wherein

The described distributed positioning of power grid oscillation sources means that the plant and station devices calculate the amplitude and sign of each branch and each oscillation power component, and the main station determines the oscillation within the network based on the broadband oscillation source positioning characteristics sent by the sub-stations. source to locate.
A distributed positioning device for power grid oscillation sources, applied at the factory and station ends, including:

The acquisition module is configured to collect synchronized phasor, harmonic and inter-harmonic phasor data based on bus and branch units;

The calculation module is configured to use synchronized phasors to calculate the location characteristics of low-frequency oscillation sources on-site when triggered by plant station oscillation monitoring alarms or commands issued by the master station, and use harmonic and inter-harmonic phasor data to calculate the location characteristics of broadband oscillation sources. quantity;

The uploading module is configured to send the low-frequency oscillation source positioning characteristic quantity and the broadband oscillation source positioning characteristic quantity to the main station for distributed positioning of power grid oscillation sources by the main station.
The device of claim 10, wherein:

In the calculation module, the use of synchronized phasor data to calculate the low-frequency oscillation source positioning feature is configured as:

The criterion for the plant station to trigger the low-frequency oscillation alarm is: within the set number of oscillations

After the low-frequency oscillation alarm is triggered or the master station command is received, the plant station device uses the collected synchronized phasor data to start the transient energy integration calculation for the bus and branch units; when the low-frequency oscillation alarm is eliminated or the set integration time is reached T max_int , the device ends the transient energy flow integral calculation;

The plant and station device uses the bus branch as a unit and uses the integration start time as the origin to perform transient energy integration curve fitting calculations and output the low-frequency oscillation characteristic quantity of each bus i branch j. The low-frequency oscillation characteristic quantity is the fitting slope k ij and intercept b ij .
The device of claim 11, wherein:

The calculation method of the fundamental wave active power P base is:

In formula (1), U a , I a , U b , I b , U c , and I c are voltage and current synchronized phasors;

The plant and station devices use synchronized phasor data to calculate the transient energy integral of each bus i branch j. The method is:

In formula (2), T max_int is the set integration time, E dis is the transient energy integral, ΔP ij =P base_ij -P ave_ij , and P ave_ij is the current average value of the fundamental wave power of branch j of bus i.
The device of claim 10, wherein:

In the calculation module, the use of harmonic and inter-harmonic phasor data to calculate broadband oscillation source positioning characteristic quantities includes:

The plant and station device calculates the instantaneous active power sampling sequence based on the voltage and current sampling values u a , ia , ub , ib , uc , ic , and extracts the dominant oscillation power component through the FFT algorithm according to Equation (3). The oscillation power The amplitude P fk and frequency f k of the component;

{P f1 ...P fn }=FFT{u a i a +u b i b +u c i c } (3);

The factory station device takes the bus branch as a unit. Within the set time T sso , the factory station device detects that the amplitude of any wide-band oscillation power component P fk continuously exceeds the set alarm setting value P sso , triggering a wide-band oscillation alarm.
The device of claim 13, wherein:

After the wide-band oscillation alarm is triggered, the factory station device tracks the n oscillation power components with the largest amplitude according to the set frequency deviation f offset in each calculation cycle. When the oscillation power component frequency f k is equal to the previously measured oscillation frequency f lastk When the deviation satisfies equation (4), it is judged to be the same oscillation power component, f lastk is updated to f k , and tracking of f k is performed in the next period;

f lastk -f offset ＜f k ＜f lastk +f offset (4);

In some embodiments, according to the frequency f k of the oscillation power component P fk and the fundamental frequency f base , the harmonic or interharmonic phasors of the phase voltage and current are matched, such as Equation (5); the voltage and current phases are obtained by matching. Quantity: U Xfk- , I Xfk- , U Xfk+ , I Xfk+ ; the subscript

f base -f k -f offset <f YX <f base -f k +f offset or f base +f k -f offset <f YX <f base +f k +f offset (5).
The device of claim 13, wherein:

The plant and station devices calculate the active power P

P fk_r =P Afk_r +P Bfk_r +P Cfk_r (7);

Calculate the accumulated energy according to the set number of cycles N
When E Nfk ≤E set- , the amplitude of the oscillation power component P fk of the bus i branch j is marked as negative; when E Nfk ≥ E set+ , the amplitude of the oscillation power component P fk is marked as positive;

The amplitude of the oscillation power after the mark is transmitted to the master station: a characteristic quantity for positioning the broadband oscillation source.
The device of claim 13, wherein:

The described distributed positioning of power grid oscillation sources means that the plant and station devices calculate the amplitude and sign of each branch and each oscillation power component, and the main station determines the oscillation within the network based on the broadband oscillation source positioning characteristics sent by the sub-stations. source to locate.
A distributed positioning device for power grid oscillation sources, applied to the main station, including:

The issuing module is configured to issue distributed positioning start commands for power grid oscillation sources;

The receiving module is configured to receive the oscillation source positioning characteristic quantity sent from the factory station;

A positioning module configured to perform distributed positioning of power grid oscillation sources based on low-frequency oscillation source positioning characteristic quantities or broadband oscillation source positioning characteristic quantities.
A distributed positioning system for power grid oscillation sources, including:

The factory station adopts the power grid oscillation source distributed positioning device according to any one of claims 10 to 16, configured to collect synchronized phasor data, harmonic and inter-harmonic phasor data, and oscillation power components, and monitor and alarm based on local oscillation Or the command issued by the master station starts the calculation of low-frequency oscillation source characteristic quantity and wide-band oscillation source characteristic quantity;

The master station adopts the power grid oscillation source distributed positioning device according to claim 17 and is configured to issue a power grid oscillation source distributed positioning start command to the factory station; receive and perform the operation according to the oscillation source characteristic quantity sent by the factory station. Locating low-frequency or broadband oscillation sources in the power grid.
An electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements any one of claims 1 to 9. The steps of the distributed positioning method of power grid oscillation sources are described.
A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the power grid oscillation source distributed positioning method described in any one of claims 1 to 9 are implemented.
A computer program, including computer readable code. When the computer readable code is run on the device, the processor in the device executes the distributed positioning of the power grid oscillation source according to any one of claims 1 to 9. Method steps.
A computer program product configured to store computer-readable instructions that, when executed, cause the computer to perform steps for implementing the distributed positioning method of power grid oscillation sources according to any one of claims 1 to 9.