Comprehensive evaluation method for operation mode of power system

Abstract

The invention relates to the technical field of power systems, and discloses a power system operation mode comprehensive evaluation method, which comprises the following steps: a data acquisition step; an index construction step; a weight determination step; a comprehensive evaluation step; a result display step; and an evaluation result storage step. According to the comprehensive evaluation method for the operation mode of the electric power system, through comprehensive and scientific steps of data acquisition, index construction, weight determination and comprehensive evaluation, the operation efficiency, reliability, economy, safety and electric energy quality of the electric power system can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a comprehensive evaluation method for power system operation modes. Background Art

[0002] As the scale and complexity of power systems continue to expand, traditional power system operation mode evaluation methods can no longer meet the needs of modern power systems. Traditional methods usually focus on the evaluation of a single indicator, such as power generation, load demand or line flow, and lack a comprehensive evaluation of the overall operation status of the power system. This single indicator evaluation method has the following main problems: Incomplete assessment: It only focuses on a single indicator and ignores important factors such as reliability, economy, safety and power quality.

[0003] Data collection is not timely: fixed time intervals or manual collection cannot reflect the system status in real time.

[0004] The indicator construction is unscientific: it lacks scientific basis and systematicity, and the evaluation results are not accurate and reliable enough.

[0005] Inaccurate weight determination: using empirical methods or subjective judgment, and lacking a scientific method for weight determination.

[0006] The evaluation results are not intuitive: they are presented in text or table form, lacking intuitiveness and visualization.

[0007] Insufficient data storage and analysis: Simple file storage or manual recording is used, and the utilization rate of historical data is low. Summary of the invention

[0008] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides a comprehensive evaluation method for the operation mode of an electric power system to solve the above problems.

[0009] (II) Technical solution To achieve the above object, the present invention provides the following technical solution: a method for comprehensively evaluating the operation mode of a power system, comprising the following steps: Step 1: Data collection step, Collect various data related to the operation mode of the power system, including but not limited to the power generation data, load demand data, line flow data, node voltage data, equipment operation status data, and power market price data of the power system; The time interval for data collection is a preset fixed time interval Δt, where the value range of Δt is 1 minute to 60 minutes.

[0010] Step 2: Indicator construction steps, Construct multiple evaluation indicators based on the collected data, including reliability indicators, economic indicators, safety indicators and power quality indicators; Among them, the reliability index includes the power shortage probability index, which is determined by counting the probability that the power supply cannot meet the load demand within a certain period of time; Economic indicators include power generation cost indicators, which calculate the total power generation cost based on power generation data and power market price data; Safety indicators include line overload rate indicators, which determine the overload rate of each line through the ratio of line flow data to line rated capacity; The power quality index includes the voltage deviation index, and the voltage deviation of each node is calculated based on the difference between the node voltage data and the rated voltage.

[0011] Step 3: Weight determination step, The weights of reliability index, economic index, safety index and power quality index are determined by using the analytic hierarchy process; A hierarchical model is constructed, with the comprehensive evaluation of the power system operation mode as the target layer, and reliability indicators, economic indicators, safety indicators and power quality indicators as the criterion layer; The judgment matrix is ​​constructed through expert scoring, and the judgment matrix is ​​tested for consistency. If the consistency ratio is less than 0.1, the judgment matrix is ​​valid, and the weight of each indicator is calculated based on the valid judgment matrix.

[0012] Step 4: Comprehensive evaluation step, Normalize each evaluation indicator and map the value of each indicator to the interval [0,1]; According to the normalized index values ​​and corresponding weights, the comprehensive evaluation value of the power system operation mode is calculated using the weighted summation method.

[0013] Preferably, in the data collection step, collecting equipment operation status data includes collecting transformer oil temperature data and circuit breaker opening and closing status data, and the collected data is transmitted to a data processing center via a sensor network, and the sensor network adopts ZigBee or Wi-Fi communication protocol.

[0014] Preferably, in the index construction step, the reliability index also includes an average power outage duration index, which is determined by counting the ratio of the total duration of power outage events within a certain period of time to the number of power outages.

[0015] Preferably, in the indicator construction step, the economic indicator also includes a network loss indicator, and the network loss of the power system is calculated based on the line flow data.

[0016] Preferably, the safety index also includes a short-circuit current level index, which is determined by calculating the short-circuit current of the power system under fault conditions.

[0017] Preferably, the power quality index also includes a frequency deviation index, which is determined according to the difference between the actual frequency and the rated frequency of the power system.

[0018] Preferably, in the weight determination step, the entropy weight method can also be used to determine the weight of each indicator, and the weight is calculated according to the information entropy of each indicator. When the entropy weight method is used, the weight determined by the entropy weight method is combined with the weight determined by the hierarchical analysis method, and the combined weight is determined by linear weighting, wherein the coefficient of the hierarchical analysis method weight is α, and the coefficient of the entropy weight method weight is 1-α, and the value range of α is 0.3-0.7.

[0019] Preferably, in the comprehensive evaluation step, an improved weighted summation method is used to calculate the comprehensive evaluation value, and the improved weighted summation method is: comprehensive evaluation value = ∑(w_i*x_i^β), where w_i is the weight of the i-th indicator, x_i is the i-th normalized indicator value, β is the adjustment coefficient, and the value range of β is 0.8-1.2.

[0020] Preferably, it also includes a result display step, in which the comprehensive evaluation value and the evaluation results of each indicator are displayed in a visual manner, and the visualization method includes but is not limited to a bar chart, a line chart, and a pie chart, and can be displayed on the power system monitoring platform.

[0021] Preferably, the method also includes an evaluation result storage step, storing the result of each evaluation in a database, the database adopts a relational database, such as MySQL or Oracle, and the stored data includes evaluation time, comprehensive evaluation value, each indicator value and each indicator weight.

[0022] Compared with the prior art, the present invention provides a comprehensive evaluation method for the operation mode of a power system, which has the following beneficial effects: Improve the efficiency of power system operation: By real-time collection and analysis of data such as power generation, load demand, and line flow in the power system, bottlenecks and problems in system operation can be discovered in a timely manner, thereby optimizing the dispatching strategy and improving the operating efficiency of the power system.

[0023] The comprehensive evaluation method can comprehensively consider the reliability, economy, safety and power quality of the power system, ensuring that the system achieves optimal operating status in many aspects.

[0024] Enhance power system reliability: By constructing reliability indicators such as power shortage probability and average power outage duration, it is possible to quantitatively evaluate the reliability level of the power system, promptly identify potential power shortage problems, and take corresponding measures to improve the reliability of the system.

[0025] Real-time monitoring of equipment operating status data, such as transformer oil temperature and circuit breaker opening and closing status, can provide early warning of equipment failures and reduce the occurrence of power outages.

[0026] Optimizing power system economics: Through economic indicators, such as power generation cost and network loss indicators, it is possible to quantitatively evaluate the economic efficiency of the power system, optimize power generation scheduling strategies, reduce power generation costs and network losses, and improve economic benefits.

[0027] Combined with electricity market price data, power generation plans can be adjusted dynamically to maximize economic benefits.

[0028] Improving power system safety: Through safety indicators such as line overload rate and short-circuit current level, the safety status of the power system can be monitored in real time, potential safety hazards can be discovered and dealt with in a timely manner, and the safe and stable operation of the system can be ensured.

[0029] The comprehensive assessment method can comprehensively consider the safety factors of the power system, avoid the limitations of single indicator evaluation, and improve the overall safety of the system.

[0030] Improve power quality: Through power quality indicators such as voltage deviation and frequency deviation, the power quality of the power system can be monitored in real time, power quality problems can be discovered and handled in a timely manner, and the stability and reliability of users' electricity use can be ensured.

[0031] The comprehensive evaluation method can comprehensively consider all aspects of power quality and improve the power quality level of the system.

[0032] Support decision making: The comprehensive evaluation method can provide comprehensive and scientific evaluation results for power system operation managers, support decision making, and optimize power system operation strategies.

[0033] Through visual display, the evaluation results can be presented intuitively, which is convenient for managers to quickly understand and analyze and improve decision-making efficiency.

[0034] Data Storage and Analysis: Storing the evaluation results in a relational database can preserve the evaluation data for a long time, facilitate subsequent query and analysis, and support the long-term optimization and improvement of the power system.

[0035] Through the analysis of historical data, we can discover the laws and trends of power system operation and provide reference for future operation strategies.

[0036] This comprehensive evaluation method for the operation mode of the power system can effectively improve the operation efficiency, reliability, economy, safety and power quality of the power system through comprehensive and scientific data collection, indicator construction, weight determination and comprehensive evaluation steps. This method can not only monitor and evaluate the operation status of the power system in real time, but also provide a scientific basis for decision-making and support the optimization and improvement of the power system. Through visual display and data storage, the evaluation results can be presented intuitively, which is convenient for managers to quickly understand and analyze and improve decision-making efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The figure is a flow chart of the evaluation steps of the present invention. DETAILED DESCRIPTION

[0038] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the invention.

[0039] See also Figure 1 , a specific implementation method of a comprehensive evaluation method for power system operation mode: 1. Data Collection Steps 1. Determine the time interval Δt for data collection The value of Δt is determined based on the scale of the power system, its operating characteristics, and the requirements for data real-time performance. For large and complex power systems with high real-time performance requirements, Δt can be set to 1-5 minutes; for relatively small and relatively stable power systems, Δt can be set to 15-60 minutes.

[0040] After selecting Δt, ensure that the data acquisition system collects data at this fixed time interval.

[0041] 2. Data collection content Power generation data At the power plant end, power sensors are used to accurately collect the real-time power generation of various power generation equipment (such as thermal power generators, hydropower generators, wind power generators, etc.). For different types of power generation equipment, their special power measurement methods and accuracy requirements need to be considered. For example, the power generation measurement of thermal power generators needs to be accurately calculated in combination with parameters such as steam flow and pressure; wind power generators need to determine the power generation based on factors such as wind speed and blade speed.

[0042] The collected power generation data is packaged according to the preset communication protocol and data format for transmission to the data processing center.

[0043] Load demand data At each load node in the power system, users' real-time power load demand is collected through smart meters and other equipment. Smart meters can accurately measure the power consumption of different types of users (residential, industrial, commercial, etc.) and upload the data in real time.

[0044] In order to ensure the accuracy of load demand data, smart meters need to be calibrated and maintained regularly, and the collected data needs to be cleaned to remove outliers and erroneous data.

[0045] Line flow data Flow monitoring devices are installed on power transmission lines. These devices can measure parameters such as active power, reactive power, and current on the lines to determine the line flow conditions.

[0046] For long-distance, high-voltage transmission lines, high-precision power flow monitoring equipment is required to cope with complex electromagnetic environments and high current and high voltage measurement requirements.

[0047] Node voltage data Install voltage transformers and data acquisition devices at each node of the power system (substation, distribution station, etc.) to measure node voltage in real time.

[0048] In order to ensure the reliability of voltage data, the voltage transformer needs to be regularly inspected for insulation and calibrated for accuracy, and the data acquisition device must have anti-interference capabilities to prevent external electromagnetic interference from affecting voltage measurement.

[0049] Equipment operating status data Transformer oil temperature data Install an oil temperature sensor on the transformer. The sensor should be installed in a position that can accurately reflect the transformer oil temperature, such as inside the transformer oil tank or near the radiator.

[0050] The oil temperature sensor transmits real-time oil temperature data to the monitoring system, which sets an oil temperature threshold alarm function. When the oil temperature exceeds the set normal range, an alarm is issued in time to remind the operation and maintenance personnel to check.

[0051] Circuit breaker opening and closing status data The circuit breaker's built-in status monitoring device obtains the opening and closing status information. These devices can accurately determine whether the circuit breaker is in the closed or open state, and transmit the status information to the data processing center in real time.

[0052] Real-time monitoring of the circuit breaker opening and closing status data is carried out to promptly detect abnormal operation or fault conditions of the circuit breaker, such as malfunction, refusal to operate, etc.

[0053] Electricity market price data Obtain power market price data from the power trading platform. The power trading platform publishes power price information for different time periods and regions at certain time intervals (such as every hour or every day).

[0054] Establish a data interface to ensure that price data can be obtained from the power trading platform in a timely and accurate manner, and correlate it with the power system operation data for analysis.

[0055] The collected data is transmitted to the data processing center through the sensor network, which can use ZigBee or Wi-Fi communication protocol.

[0056] ZigBee Communication Protocol For some sensor nodes that are more dispersed, have smaller data volumes and lower power consumption requirements, such as some equipment operation status monitoring sensors, the ZigBee protocol can be used to build a wireless sensor network.

[0057] ZigBee network adopts star, tree or mesh topology, and optimizes the configuration according to the physical layout of the power system and the distribution of sensors. The data collected by each sensor node is aggregated and transmitted to the data processing center through the ZigBee coordinator.

[0058] Wi-Fi Communication Protocol In some areas with large data volumes, high transmission speed requirements and Wi-Fi coverage, such as some data acquisition equipment inside substations, the Wi-Fi protocol can be used for data transmission.

[0059] Establish Wi-Fi access points to ensure that sensor devices can stably connect to the Wi-Fi network and transmit data. At the same time, set up security on the Wi-Fi network to prevent data leakage and illegal access.

[0060] 2. Indicator Construction Steps 1. Construct multiple evaluation indicators based on the collected data, including reliability indicators, economic indicators, safety indicators and power quality indicators.

[0061] Reliability Index Power shortage probability indicator Set the statistical period, such as one day, one week or one month.

[0062] In each statistical period, the total power supply (the sum of the power generation of all power generation equipment) is compared with the total load demand (the sum of the load demand of all load nodes).

[0063] When the total power supply is less than the total load demand, it is recorded as a power shortage event.

[0064] Power shortage probability = number of power shortage events / total number of times in the statistical period.

[0065] Average outage duration indicator Establish a power outage event monitoring mechanism to determine the occurrence and end time of power outage events by monitoring node voltage data, line flow data, etc.

[0066] When the node voltage is lower than the set power outage threshold (such as less than 10% of the rated voltage) and lasts for a certain period of time (such as more than 1 minute), it is determined that the power outage event has begun; when the voltage returns to the normal range and remains stable for a certain period of time (such as more than 5 minutes), it is determined that the power outage event has ended.

[0067] The duration of each power outage event is counted, and the ratio of the total duration of power outage events within a certain period of time to the number of power outages is calculated.

[0068] Economic indicators Power generation cost index Based on the power generation data, determine the power generation of each power generation method (such as thermal power generation, hydropower generation, wind power generation, etc.) in different time periods.

[0069] Combined with the electricity market price data corresponding to different power generation methods obtained from the electricity market, the power generation cost of each power generation method is calculated. For example, the cost of thermal power generation includes fuel cost, equipment maintenance cost, etc. The fuel consumption cost is calculated based on the power generation and the corresponding price, and the total cost of thermal power generation is obtained by adding the shared cost of equipment maintenance; the cost of hydropower generation mainly considers equipment depreciation, operation and maintenance costs, etc., and the total cost is obtained based on the power generation and the corresponding cost calculation method; the cost of wind power generation includes wind turbine equipment depreciation, operation and maintenance and management costs, etc., and the total cost of wind power generation is calculated according to the power generation.

[0070] Add up the generation costs of various power generation methods to obtain the total generation cost of the power system.

[0071] Network loss index The power loss of each line is calculated based on the active power and reactive power in the line flow data. The power loss calculation formula is: $P_{loss}=I^2R$ (for active power loss, where $I$ is the line current and $R$ is the line resistance) and $Q_{loss}=I^2X$ (for reactive power loss, where $X$ is the line reactance).

[0072] Summarizing the power losses of all lines, we get the network loss of the power system.

[0073] Safety indicators Line overload rate indicator For each transmission line, obtain the actual power (including active power and reactive power) in its line flow data.

[0074] Calculate the line overload rate based on the rated capacity of the line (determined by the design parameters of the line). Overload rate = (actual power / rated capacity) × 100%.

[0075] Set an overload rate threshold, such as 120%. When the line overload rate exceeds the threshold, it is marked as an overloaded line for subsequent safety analysis and processing.

[0076] Short circuit current level indicator A power system fault analysis model is established, taking into account the topological structure and equipment parameters of the power system (such as generator reactance, transformer reactance, line reactance, etc.).

[0077] Different types of fault scenarios (such as three-phase short circuit, two-phase short circuit, etc.) are set in the fault analysis model, and the short-circuit current of the power system under each fault condition is calculated.

[0078] Based on the calculation results of the short-circuit current, it is evaluated whether the short-circuit current level of the power system in the event of a fault is within the tolerance range of the equipment to determine the safety of the power system.

[0079] Power quality indicators Voltage deviation index For each node, obtain its node voltage data.

[0080] Calculate the voltage deviation based on the rated voltage (determined by the design standard of the power system). Voltage deviation = (node ​​voltage - rated voltage) / rated voltage × 100%.

[0081] Set the qualified range of voltage deviation, such as ±5%. When the node voltage deviation exceeds this range, it is judged as a node with unqualified voltage quality so that corresponding voltage regulation measures can be taken.

[0082] Frequency Deviation Indicator The actual frequency data of the power system is obtained. The frequency of the power system is measured in real time through a frequency monitoring device.

[0083] Based on the rated frequency (such as 50Hz or 60Hz, depending on the power standards in the area), calculate the frequency deviation. Frequency deviation = (actual frequency - rated frequency).

[0084] The allowable range of frequency deviation is set, such as ±0.2Hz. When the frequency deviation exceeds this range, the frequency regulation mechanism is triggered, such as adjusting the output of the generator, to maintain the frequency stability of the power system.

[0085] 3. Weight determination steps 1. Build a hierarchical model Target layer: Comprehensive assessment of the operation mode of the power system. The overall goal of the assessment is to conduct a comprehensive and integrated evaluation of the operation mode of the power system.

[0086] Criteria layer: reliability index, economic index, safety index and power quality index, which decomposes the comprehensive evaluation target into the index system of these four main aspects.

[0087] 2. Determine weights using the analytic hierarchy process Constructing a judgment matrix through expert scoring Experts in the field of power systems (including power engineers, power system researchers, power operation managers, etc.) are invited to score the relative importance of reliability indicators, economic indicators, safety indicators and power quality indicators.

[0088] For example, a 1-9 scale is used, where 1 means that two indicators are equally important, and 9 means that one indicator is extremely important than the other. Experts score the relative importance of each two indicators based on their professional knowledge and experience and construct a judgment matrix.

[0089] Consistency test of judgment matrix Calculate the maximum eigenvalue $\lambda_{max}$ and consistency index $CI=(\lambda_{max}-n) / (n-1)$ of the judgment matrix (where $n$ is the order of the judgment matrix).

[0090] Find the average random consistency index $RI$ (there is a corresponding value table based on the order of the judgment matrix) and calculate the consistency ratio $CR=CI / RI$.

[0091] If the consistency ratio is less than 0.1, the judgment matrix is ​​valid; if it is greater than 0.1, experts are required to re-score and adjust the judgment matrix until the consistency requirements are met.

[0092] Calculate the weight of each indicator according to the effective judgment matrix By calculating the eigenvector of the judgment matrix, the weight vectors of the reliability index, economic index, safety index and power quality index are obtained.

[0093] 3. Determine weights using entropy weight method Calculate the information entropy of each indicator For each evaluation indicator, assuming that there are $m$ evaluation objects (which can be the operation conditions of the power system in different time periods or the operation modes of different power systems), the $i$th indicator value of each evaluation object is $x_{ij}$ ($j=1,2,\cdots,m$).

[0094] First, normalize the index value to get $y_{ij}$. For positive indicators (the larger the index value, the better), $y_{ij}=x_{ij} / \sum_{j=1}^{m}x_{ij}$; for negative indicators (the smaller the index value, the better), $y_{ij}=1-x_{ij} / \sum_{j=1}^{m}x_{ij}$.

[0095] Calculate the information entropy $E_i=-k\sum_{j=1}^{m}y_{ij}\lny_{ij}$ of the $i$th indicator (where $k=1 / \lnm$).

[0096] Calculate weights based on information entropy The entropy weight of the $i$th indicator $w_i=(1-E_i) / \sum_{i=1}^{n}(1-E_i)$ (where $n$ is the number of indicators).

[0097] 4. Determination of combination weight When the entropy weight method is used, the weights determined by the entropy weight method are combined with the weights determined by the analytic hierarchy process.

[0098] The combined weight is determined by linear weighting. Let the coefficient of the AHP weight be α, the coefficient of the entropy weight method weight be 1-α, and the value range of α is 0.3-0.7. For example, when α=0.5, the combined weight $W_i=0.5\timesw_{i1}+0.5\timesw_{i2}$ (where $w_{i1}$ is the weight of the $i-th indicator determined by the AHP method, and $w_{i2}$ is the weight of the $i$-th indicator determined by the entropy weight method).

[0099] 4. Comprehensive Assessment Steps Index normalization For each evaluation metric, a normalization method is determined according to its properties.

[0100] For positive indicators (such as the power shortage probability indicator in the reliability indicator, the smaller the value, the better, and it can be converted into a positive indicator, such as subtracting the indicator value from 1), the formula $x_{i}^{}=\frac{x_{i}-min(x_{i})}{max(x_{i})-min(x_{i})}$ is used for normalization, where $x_{i}$ is the original indicator value, $x_{i}^{}$ is the normalized indicator value, $min(x_{i})$ and $max(x_{i})$ are the minimum and maximum values ​​of the indicator among all evaluation objects, respectively.

[0101] For negative indicators (such as the power generation cost indicator in the economic indicators, the larger the value, the worse), the formula $x_{i}^{*}=\frac{max(x_{i})-x_{i}}{max(x_{i})-min(x_{i})}$ is used for normalization.

[0102] The value of each indicator is mapped to the interval [0,1] to ensure that all indicators are comprehensively evaluated under the same dimension.

[0103] Calculation of comprehensive evaluation value According to the normalized index values ​​and corresponding weights, the comprehensive evaluation value of the power system operation mode is calculated using the weighted summation method.

[0104] The improved weighted summation method is adopted: comprehensive evaluation value = ∑(w_i*x_i^β), where w_i is the weight of the i-th indicator, x_i is the i-th normalized indicator value, β is the adjustment coefficient, and the value range of β is 0.8-1.2.

[0105] During the calculation process, the β value can be adjusted according to the actual operation of the power system and the focus of the evaluation. For example, when more attention is paid to the balance between the indicators, the β value can be set to 1; when the impact of certain important indicators is to be highlighted, the β value can be set to 1.2, so that these indicators account for a relatively larger proportion in the comprehensive evaluation value.

[0106] 5. Result display steps Visualization method selection Bar Chart Used to show the proportion of different indicators in the comprehensive evaluation. Reliability indicators, economic indicators, safety indicators and power quality indicators are used as different columns. The height of the column represents the weight of the indicator in the comprehensive evaluation value or the normalized indicator value. The bar chart can be used to intuitively compare the relative importance or performance of each indicator.

[0107] For each indicator, the sub-indicators it contains can be further broken down and displayed. For example, in the reliability indicator column, the power shortage probability indicator and the average power outage duration indicator can be broken down and displayed according to their respective weights or numerical proportions in the reliability indicator, so that users can understand the internal composition of each indicator in more detail.

[0108] Line chart It is used to show the changes in the comprehensive evaluation value of the power system in different time periods. With time as the horizontal axis and the comprehensive evaluation value as the vertical axis, a line graph is drawn. Through the line graph, the fluctuation trend of the comprehensive evaluation value of the power system operation mode over time can be observed, and the stability and change law of the power system operation can be analyzed.

[0109] At the same time, you can add the broken lines of each major indicator (such as reliability index, economic index, etc.) to the same broken line chart to analyze which indicators caused the change in the comprehensive evaluation value. For example, if you find that the comprehensive evaluation value decreases in a certain period of time, and the broken line of the reliability index also shows a downward trend, you can further analyze which sub-indicators in the reliability index have changed, so as to find out the key factors affecting the operation mode of the power system.

[0110] Pie Chart Used to show the contribution ratio of each indicator in the comprehensive evaluation value. The comprehensive evaluation value is regarded as a whole, and it is divided into different sectors according to the weight of each indicator. Each sector represents the proportion of an indicator in the comprehensive evaluation value. The pie chart can intuitively show the relative contribution of each indicator to the comprehensive evaluation result.

[0111] Demonstrate platform capabilities Display on the power system monitoring platform, the monitoring platform should have the following functions: Real-time update function: It can obtain the latest evaluation results in real time and update the display content in time to ensure that users see the current operation mode evaluation of the power system.

[0112] Interactive function: Users can view more detailed indicator information by clicking on an area in the chart (such as a column in a bar chart, a sector area in a pie chart), including the original indicator value, normalized indicator value, weight calculation process, etc.

[0113] Multi-screen display support: Different visualization contents can be displayed on multiple screens at the same time according to different monitoring needs, such as a line chart of the comprehensive evaluation value on one screen and a bar chart and pie chart of each indicator on another screen.

[0114] 6. Evaluation result storage steps The results of each evaluation are stored in a database using a relational database such as MySQL or Oracle. The stored data includes the evaluation time, comprehensive evaluation value, each indicator value and each indicator weight for subsequent query and analysis.

[0115] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A comprehensive evaluation method for power system operation mode, characterized in that: The following steps are involved: Step 1: Data collection step, Collect various data related to the operation mode of the power system, including but not limited to the power generation data, load demand data, line flow data, node voltage data, equipment operation status data, and power market price data of the power system; The time interval for data collection is a preset fixed time interval Δt, wherein the value range of Δt is 1 minute to 60 minutes. Step 2: Indicator construction steps, Constructing multiple evaluation indicators based on the collected data, wherein the evaluation indicators include reliability indicators, economic indicators, safety indicators and power quality indicators; Among them, the reliability index includes the power shortage probability index, which is determined by counting the probability that the power supply cannot meet the load demand within a certain period of time; Economic indicators include power generation cost indicators, which calculate the total power generation cost based on power generation data and power market price data; Safety indicators include line overload rate indicators, which determine the overload rate of each line through the ratio of line flow data to line rated capacity; The power quality index includes the voltage deviation index, and the voltage deviation of each node is calculated based on the difference between the node voltage data and the rated voltage. Step 3: Weight determination step, The weights of reliability index, economic index, safety index and power quality index are determined by using the analytic hierarchy process; A hierarchical model is constructed, with the comprehensive evaluation of the power system operation mode as the target layer, and reliability indicators, economic indicators, safety indicators and power quality indicators as the criterion layer; The judgment matrix is ​​constructed through expert scoring, and the judgment matrix is ​​tested for consistency. If the consistency ratio is less than 0.1, the judgment matrix is ​​valid, and the weight of each indicator is calculated based on the valid judgment matrix. Step 4: Comprehensive evaluation step, Normalize each evaluation indicator and map the value of each indicator to the interval [0,1]; According to the normalized index values ​​and corresponding weights, the comprehensive evaluation value of the power system operation mode is calculated using the weighted summation method.

2. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: In the data collection step, collecting equipment operation status data includes collecting transformer oil temperature data and circuit breaker opening and closing status data, and the collected data is transmitted to a data processing center through a sensor network, and the sensor network adopts ZigBee or Wi-Fi communication protocol.

3. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: In the index construction step, the reliability index also includes an average power outage duration index, which is determined by counting the ratio of the total duration of power outage events within a certain period of time to the number of power outages.

4. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: In the indicator construction step, the economic indicator also includes a network loss indicator, and the network loss of the power system is calculated based on the line flow data.

5. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: The safety index also includes a short-circuit current level index, which is determined by calculating the short-circuit current of the power system under fault conditions.

6. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: The power quality index also includes a frequency deviation index, which is determined according to the difference between the actual frequency and the rated frequency of the power system.

7. A method for comprehensive evaluation of power system operation mode according to claim 1, characterized in that: In the weight determination step, the entropy weight method can also be used to determine the weight of each indicator, and the weight is calculated according to the information entropy of each indicator. When the entropy weight method is used, the weight determined by the entropy weight method is combined with the weight determined by the hierarchical analysis method, and the combined weight is determined by linear weighting, wherein the coefficient of the hierarchical analysis method weight is α, and the coefficient of the entropy weight method weight is 1-α, and the value range of α is 0.3-0.

7.

8. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: In the comprehensive evaluation step, an improved weighted summation method is used to calculate the comprehensive evaluation value, and the improved weighted summation method is: comprehensive evaluation value = ∑(w_i*x_i^β), where w_i is the weight of the i-th indicator, x_i is the i-th normalized indicator value, β is the adjustment coefficient, and the value range of β is 0.8-1.

2.

9. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: It also includes a result display step five, which displays the comprehensive evaluation value and the evaluation results of each indicator in a visual manner. The visualization method includes but is not limited to a bar chart, a line chart, and a pie chart, and can be displayed on the power system monitoring platform.

10. A comprehensive evaluation method for power system operation mode according to claim 1, characterized in that: The method also includes an evaluation result storage step six, storing the result of each evaluation in a database, wherein the database adopts a relational database, such as MySQL or Oracle, and the stored data includes evaluation time, comprehensive evaluation value, each indicator value and each indicator weight.

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