Method and system for reactive power assessment and performance evaluation of unit

Abstract

The invention discloses a unit reactive power assessment and performance evaluation method and system, and relates to the technical field of power system dynamic monitoring, and the method comprises the steps: reading parameters used for unit reactive power assessment and performance evaluation; capturing real-time data of the unit, and monitoring, calculating and counting the data; providing reactive compensation equipment switching suggestions; performing assessment-free judgment processing; a visual human-computer interface is provided, and statistical curve data are monitored and updated in real time. According to the unit reactive power assessment and performance evaluation method provided by the invention, real-time measurement is carried out on parameters of a unit bus based on a PMU / WAMS system, and meanwhile, high-speed accurate sampling with the same time scale is carried out, so that an instantaneous value can be provided, a phase value can also be provided, and the reliability of acquired data is greatly improved; the method comprises the following steps: reading parameters of reactive compensation equipment, and switching suggestions according to the reactive compensation equipment; and examination-free analysis is automatically carried out on phase-in examination and phase-out examination, so that the accuracy and the automation degree of reactive examination are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic monitoring of electric power systems, and in particular to a method and system for reactive power assessment and performance evaluation of a generating unit. Background Art

[0002] In recent years, with the development of new energy, new energy such as wind power and photovoltaics has achieved unprecedented development in my country. However, due to the lack of support capacity of synchronous generators such as conventional hydropower and thermal power, new energy has led to increasingly prominent stability problems such as weakened grid strength, transient voltage instability, and wide-band oscillation. Therefore, in order to ensure the safe and stable operation of the power system, the power grid company has continuously improved the requirements for the dynamic grid-connected capabilities such as frequency regulation and voltage regulation of traditional hydropower and thermal power plants. The current analysis method of reactive power regulation capability requires manual analysis of the original change curves of various parameters. In order to improve the stability of the power system, reduce the work pressure of technicians, and improve the level of automation assistance of the power system, it is necessary to study a reactive power assessment and performance evaluation method for the unit based on a high-precision PMU / WAMS system. Summary of the invention

[0003] In view of the above-mentioned problems, the present invention is proposed.

[0004] Therefore, the technical problem solved by the present invention is that the existing analysis method of reactive power regulation capability has the problems of poor stability, low precision, inability to automatically analyze and adjust, and waste of manpower and material resources.

[0005] To solve the above technical problems, the present invention provides the following technical solutions: a method for reactive power assessment and performance evaluation of a unit, comprising reading parameters used for reactive power assessment and performance evaluation of the unit; capturing real-time data of the unit and monitoring, calculating and statistics the data; providing suggestions for switching on reactive power compensation equipment; performing assessment-free judgment processing; providing a visual human-machine interface, and real-time monitoring and updating of statistical curve data.

[0006] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, wherein: the reading of parameters used for reactive power assessment and performance evaluation of the unit includes reading reactive power assessment parameters and unit parameters saved in a CSV file.

[0007] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, the real-time data of the unit is captured and the data is monitored, calculated and counted, including calling the bus voltage, power factor, reactive output of the unit and other data measured in real time in the PMU / WAMS system, and calculating the parameters from the parameter reading module and the PMU measurement module.

[0008] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, the aforementioned assessment-free judgment processing and the proposal for reactive power compensation equipment switching include automatically making assessment-free judgment and processing for the leading phase assessment and the lagging phase assessment.

[0009] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, wherein: the performing of assessment-free judgment processing and proposing reactive power compensation equipment switching suggestions include proposing reactive power compensation equipment switching suggestions based on the assessment scores.

[0010] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, the provision of a visual human-machine interface, real-time monitoring and updating of statistical curve data includes realizing real-time monitoring of data and supporting display of the latest curve data at a display interval of 10 minutes.

[0011] As a preferred solution of the reactive power assessment and performance evaluation method of the unit described in the present invention, the provision of a visual human-machine interface, real-time monitoring, and updating of statistical curve data include functions such as reactive power compensation suggestions and parameter control, while supporting historical data query, including bus voltage, actual reactive voltage and other data of any day including the current day.

[0012] Another object of the present invention is to provide a unit reactive power assessment and performance evaluation system, which can measure the parameters of the unit bus in real time through the PMU / WAMS system, greatly increasing the reliability of the collected data; at the same time, it can automatically perform assessment-free analysis on the leading phase assessment and the lagging phase assessment, thereby improving the accuracy and automation of the reactive power assessment.

[0013] As a preferred solution of the reactive power assessment and performance evaluation system of the unit described in the present invention, it includes: a parameter reading module, a PMU measurement module, a data calculation module, and a visual human-machine interface module. The parameter reading module is used to read the reactive power assessment parameters and unit parameters stored in the csv file, and use them in the data calculation module; the PMU measurement module is used to call the bus voltage, power factor, unit reactive output and other data measured in real time in the PMU / WAMS system, and the above parameters will be used by the data calculation module; the data calculation module is used to automatically judge and process the leading phase assessment and the lagging phase assessment without assessment; the visual human-machine interface module is used to realize the functions of real-time data monitoring, historical data query, reactive power compensation suggestions, parameter control, etc.

[0014] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of a method for reactive power assessment and performance evaluation of a unit.

[0015] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for reactive power assessment and performance evaluation of a unit.

[0016] Beneficial effects of the present invention: The reactive power assessment and performance evaluation method provided by the present invention uses a PMU / WAMS system to measure the parameters of the unit bus in real time, and simultaneously performs high-speed and accurate sampling with the same time scale, which can not only provide instantaneous values, but also phase values, greatly increasing the reliability of the collected data; by reading the reactive compensation equipment parameters, and proposing switching suggestions for reactive compensation equipment based on the current reactive output and bus voltage level; automatically performing assessment-free analysis on the leading phase assessment and the lagging phase assessment, improving the accuracy and automation of the reactive power assessment. The present invention has achieved significant improvements in reliability, accuracy, and automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0018] Figure 1 An overall flow chart of a method for reactive power assessment and performance evaluation of a unit provided in the first embodiment of the present invention.

[0019] Figure 2 Another flow chart of a method for reactive power assessment and performance evaluation of a generator set provided in the first embodiment of the present invention.

[0020] Figure 3 A calculation flow chart of a method for reactive power assessment and performance evaluation of a unit provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0022] Example 1, reference Figure 1-Figure 3 , which is an embodiment of the present invention, provides a method for reactive power assessment and performance evaluation of a unit, comprising:

[0023] S1: Read the parameters used for reactive power assessment and performance evaluation of the unit.

[0024] Furthermore, reading the parameters used for reactive power assessment and performance evaluation of the unit includes reading reactive power assessment parameters and unit parameters saved in a CSV file.

[0025] S2: Capture the real-time data of the unit and monitor, calculate and count the data.

[0026] Furthermore, the real-time data of the unit is captured and the data is monitored, calculated, and counted, including calling the bus voltage, power factor, unit reactive output and other data measured in real time in the PMU / WAMS system, by calculating the parameters from the parameter reading module and the PMU measurement module.

[0027] S3: Perform assessment-free judgment processing and propose switching suggestions for reactive power compensation equipment

[0028] Further, refer to Figure 2 As an assessment step, the bus voltage is read and compared with the rated bus voltage to determine whether the bus voltage (wind power station is the grid connection point) exceeds the limit (±15%). If it exceeds the limit, determine whether it exceeds the upper limit or the lower limit. If the limit exceeds the limit for more than a certain period of time (which can be set through the parameter control interface, the same below), the bus voltage can be considered unqualified, and the event will be assessed as an advanced phase (exceeding the upper limit) or a delayed phase (exceeding the lower limit) until the bus voltage no longer exceeds the limit.

[0029] According to the assessment type obtained by calculation and comparison, read the lower limit of the leading phase or the upper limit of the lagging phase. If the reactive power actually absorbed by the unit is more than the lower limit of the leading phase, or the reactive power actually generated by the unit is more than the upper limit of the lagging phase, it is considered that this time period is exempt from assessment.

[0030] The difference between the reactive output of the unit and the lower limit of the leading phase / the upper limit of the lagging phase is integrated over time to obtain the reactive integrated power of the bus voltage abnormality event, and reactive compensation suggestions are issued to the system based on the difference.

[0031] It should be noted that the absolute value of the reactive integrated power of the unit is summed up every day to obtain the total reactive integrated power of the day. The final value of the reactive integrated power is then calculated by weighting the voltage fluctuation rate every day. The specific formula is as follows:

[0032]

[0033] in, It indicates the total integrated electricity of all events on the day; Dv indicates the voltage fluctuation rate of the day, which is calculated as (maximum voltage of the day - minimum voltage of the day) / reference voltage; Ref indicates the reference voltage fluctuation rate, which is 3.5% in 220kV power grid and 3% in 500kV power grid (both can be set). The result is assessed at 2 points / 10,000 kVar·h (can be set).

[0034] S4: Provides a visual human-machine interface to monitor and update statistical curve data in real time.

[0035] Furthermore, according to the measurement data of the PMU measurement module and the data calculated by the data calculation module, the operation data monitoring curve and reactive event curve of each unit are drawn. The operation data monitoring curve includes the actual bus voltage curve, the actual reactive power output authority and the rated bus voltage data; the reactive event curve can automatically query the latest record in the reactive assessment result table after selecting the unit and display the curve information and event information. The date can also be freely set for query and display. The curve information includes the excitation current curve, the actual reactive curve, the theoretical reactive curve and the actual voltage curve; the event information includes the basic parameters of the unit, voltage information (including event start voltage, extreme voltage, reactive extreme point voltage, end voltage, voltage change), reactive information (including event start reactive, voltage extreme point reactive, extreme reactive, end reactive, reactive change) and theoretical reactive information.

[0036] Example 2, an embodiment of the present invention, provides a method for reactive power assessment and performance evaluation of a unit. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0037] First, the test environment is set up and a typical generator set system is selected, including PMU (Phasor Measurement Unit) and WAMS (Wide Area Measurement System) equipment, which can obtain bus voltage, power factor and reactive output data in real time.

[0038] The reactive power assessment data and related unit parameters of all units are saved in CSV file format in advance to facilitate subsequent reading and processing.

[0039] The evaluation indicators include parameters such as the unit's reactive output, power factor, and bus voltage, and automatic assessment-free judgment is performed on the leading phase assessment and the lagging phase assessment.

[0040] First, the system reads the reactive power assessment parameters and unit operation parameters saved in the CSV file. The system starts to obtain the real-time data of the unit's bus voltage, current, power factor, etc. by calling the data monitored in real time by PMU / WAMS.

[0041] The system begins to obtain data such as voltage, current, power factor, etc. in real time through PMU / WAMS, and dynamically monitors and counts all data. All real-time data is recorded and summarized in the database in a timely manner to provide data support for subsequent calculations and evaluations.

[0042] When the reactive output data and power factor of the unit meet certain standards, the system will automatically make an assessment exemption judgment. If the assessment exemption conditions are met, the system will propose a reactive compensation device switching. This step processes the assessment results through the data calculation module and automatically decides whether to exempt the assessment.

[0043] During the experiment, the system displays the statistical curves of various evaluation parameters in real time through a visual human-machine interface. The interface displays the changing trends of bus voltage, reactive power output, power factor and other data at intervals of 10 minutes. At the same time, the interface supports querying historical data, including detailed data for the current day and any other day.

[0044] After the experiment, the system analyzes all the collected data and comprehensively calculates the performance evaluation score of the computer group. By comparing the reactive output data and power factor of the unit in different time periods, the system can accurately judge the operating status of the unit and give optimization suggestions.

[0045] Table 1 Experimental data comparison table

[0046]

[0047] Referring to Table 1, it can be seen that according to the reactive output and power factor of the unit, this method can effectively reduce unnecessary reactive assessments through the mechanism of automatic assessment-free judgment (as shown in the "assessment-free judgment" column). In the table, when the reactive assessment score reaches a certain standard, the system will automatically judge it as assessment-free (for example, the two sets of data at 10:20 and 10:50 on 2024-11-01). This can improve the efficiency of the assessment without reducing the accuracy of the assessment.

[0048] Based on the results of the assessment-free judgment, when the unit's assessment score is lower than a certain threshold (such as 75%), the system will automatically give suggestions for switching on reactive compensation equipment. In the period of 2024-11-01 10:30 and 10:40 in the table, the system puts forward suggestions for reactive compensation based on the changes in reactive output and power factor. This is of great significance for ensuring the stability of unit operation and optimizing the use of reactive compensation equipment.

[0049] Compared with the traditional reactive power assessment method, this system can reduce the reactive power assessment burden on the unit through real-time data monitoring and assessment-free judgment, and optimize reactive power output and reduce equipment loss by dynamically adjusting compensation equipment. Through data comparison, it can be seen that when the system gives reactive power compensation suggestions, the reactive power output and power factor of the unit remain in a relatively stable state, avoiding unnecessary equipment investment and waste.

[0050] Embodiment 3, an embodiment of the present invention provides a reactive power assessment and performance evaluation system for a generating unit, including a parameter reading module, a PMU measurement module, a data calculation module, and a visual human-machine interface module.

[0051] Among them, the parameter reading module is used to read the reactive assessment parameters and unit parameters saved in the csv file, and use them in the data calculation module; the PMU measurement module is used to call the bus voltage, power factor, unit reactive output and other data measured in real time in the PMU / WAMS system, and the above parameters will be used by the data calculation module; the data calculation module is used to automatically judge and process the leading phase assessment and the lagging phase assessment; the visual human-machine interface module is used to realize real-time data monitoring, historical data query, reactive compensation suggestions, and parameter control functions.

[0052] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0053] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0054] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering, or processing in another suitable manner as necessary, and then stored in a computer memory.

[0055] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc. It should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not limited. Although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

[0056] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for reactive power assessment and performance evaluation of a unit, characterized in that: include: Read the parameters used for reactive power assessment and performance evaluation of the unit; Capture the real-time data of the unit and monitor, calculate and count the data; Conduct assessment-free judgment and make suggestions on switching on and off reactive power compensation equipment; Provides a visual human-computer interface to monitor and update statistical curve data in real time.

2. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 1, characterized in that: The reading of parameters used for reactive power assessment and performance evaluation of the unit includes reading reactive power assessment parameters and unit parameters stored in a CSV file.

3. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 2, characterized in that: The real-time data of the unit is captured and the data is monitored, calculated and counted, including calling the bus voltage, power factor and reactive output data of the unit measured in real time in the PMU / WAMS system, and calculating the parameters from the parameter reading module and the PMU measurement module.

4. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 3, characterized in that: The performing of assessment-free judgment processing and proposing reactive compensation equipment switching suggestions include automatically performing assessment-free judgment and processing on leading phase assessment and lagging phase assessment.

5. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 4, characterized in that: The assessment-free judgment process includes proposing switching recommendations for reactive power compensation equipment based on the assessment score.

6. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 5, characterized in that: The provision of a visual human-machine interface, real-time monitoring, and updating of statistical curve data include achieving real-time monitoring of data and supporting display of the latest curve data at a display interval of 10 minutes.

7. The reactive power assessment and performance evaluation method of a generator set as claimed in claim 6, characterized in that: The provided visual human-machine interface monitors and updates the statistical curve data in real time, including reactive power compensation suggestions and parameter control functions, and supports historical data query, including bus voltage and actual reactive power voltage data of any day including the current day.

8. A system using the reactive power assessment and performance evaluation method of a generating unit as claimed in any one of claims 1 to 7, characterized in that: Including parameter reading module, PMU measurement module, data calculation module, and visual human-computer interface module; The parameter reading module is used to read reactive power assessment parameters and unit parameters stored in a csv file and use them in the data calculation module; The PMU measurement module is used to call the bus voltage, power factor, and unit reactive output data measured in real time in the PMU / WAMS system; The data calculation module is used to automatically judge and process the phase-advancing assessment and phase-delay assessment without assessment; The visual human-machine interface module is used to realize real-time monitoring of data, historical data query, reactive power compensation suggestion, and parameter control functions.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the unit reactive power assessment and performance evaluation method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the reactive power assessment and performance evaluation method of a unit as described in any one of claims 1 to 7 are implemented.

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