Photovoltaic reverse transmission out-of-limit management and control method based on new energy access and related equipment

Abstract

The invention belongs to the technical field of power distribution network management and control, and particularly relates to a photovoltaic reverse transmission out-of-limit management and control method and related equipment based on new energy access, and the method comprises the steps: obtaining new energy data, and dividing a power flow out-of-limit analysis decision based on an access scene of the new energy data; obtaining a target analysis object in the power distribution network, and searching a photovoltaic reverse transmission out-of-limit line according to the load rate of the target analysis object; carrying out branch switching of a main line on the photovoltaic reverse transmission out-of-limit line, carrying out load flow calculation on the switched line, and adjusting the operation mode of the power distribution network after the new energy data is accessed until each operation state data meets a constraint condition; and if the photovoltaic reverse transmission out-of-limit line still exists in the power distribution network after the constraint condition is met, adjusting the photovoltaic reverse transmission out-of-limit line according to the day-ahead scene analysis strategy or the intra-day scene analysis strategy. The analysis data provided by the invention is higher in reliability, the management and control accuracy is more accurate, the capability of managing and controlling the power flow out-of-limit of the power distribution network is improved, and safe and stable operation of the power distribution network is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of distribution network control, and specifically relates to a photovoltaic reverse transmission over-limit control method based on new energy access and related equipment. Background Art

[0002] With the access of a large number of loads and distributed power sources to the power grid, the structure of the power grid has changed greatly, and the acceptable capacity of the lines and substations also needs to be dynamically adjusted. Therefore, it is necessary to analyze the acceptable load capacity margin and photovoltaic capacity margin of the lines and substations on the basis of comprehensive evaluation of the grid carrying capacity, adjustable margin, and reactive power response characteristics. With the rapid development of new energy, the proportion of distributed generation (DG) in the distribution network is getting higher and higher. The introduction of DG has changed the radial structure of the distribution network, resulting in the original unidirectional load transfer strategy no longer being applicable to the bidirectional load transfer strategy. The bidirectional flow caused by DG access has brought new problems to the adjustment of the operation mode, such as flow over-limit and node voltage exceeding the standard. These problems not only affect the safe and stable operation of the distribution network, but also affect the absorption efficiency and economic benefits of DG.

[0003] There are some research results in the existing technology for the problem of power flow over-limit after DG is connected to the distribution network, including the proposal to balance the line load rate and node voltage by adjusting the DG output and load demand, or to coordinate the DG output and line load rate through fuzzy reasoning and PID controller, or to reduce line loss and improve voltage quality by optimizing the DG output and switch state. However, simply relying on the adjustment of DG output to solve the power flow over-limit problem without considering the impact of the operation of the distribution network itself on the power flow distribution, the data reliability is poor, and the accuracy of the power flow over-limit control of the distribution network is low. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of poor data reliability and low accuracy of distribution network power flow over-line control in the prior art due to the simple reliance on the adjustment of DG output to solve the power flow over-limit problem. A photovoltaic reverse transmission over-limit control method based on new energy access and related equipment are proposed. After the distribution network is connected to the new energy data, the method solves the power flow over-limit problem by comprehensively considering the adjustment of the distribution network operation mode and combining the day-ahead scenario analysis strategy and the intra-day scenario analysis strategy. The over-limit analysis and adjustment are combined with the new energy itself and the operation mode of the distribution network. The data reliability is higher, and the photovoltaic reverse transmission over-limit line can be determined more accurately and the power flow calculation can be performed. The more accurate the calculation result, the better the performance. The final control results are more accurate, which is more conducive to improving the control capabilities of power flow over-limit in distribution networks, ensuring safe and stable operation of distribution networks, and reducing failures and losses caused by power flow over-limit. According to the new energy data access scenario, the power flow over-limit analysis and decision-making are divided into two scenarios: day-ahead and intraday. The corresponding strategy is selected according to the access scenario for over-limit adjustment, and real-time data and forecast data are fully utilized for over-limit analysis and decision-making. For photovoltaic reverse transmission over-limit lines, the branches of the main lines are exchanged and power flow calculation and constraint condition analysis are performed, so as to adjust the operation mode of the distribution network, quickly find a suitable branch exchange plan, and improve the adjustment efficiency of the operation mode.

[0005] In a first aspect, an embodiment of the present invention provides a photovoltaic reverse transmission over-limit control method based on new energy access, comprising the following steps: Acquire new energy data, and divide power flow over-limit analysis decisions based on access scenarios of the new energy data, wherein the power flow over-limit analysis decisions include a day-ahead scenario analysis strategy for power flow analysis based on forecast data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on real-time data of the distribution network after access to the new energy data; Acquire a target analysis object in the distribution network connected to the new energy data, and find a photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object; For the photovoltaic reverse transmission over-limit line, the branch line of the trunk line is exchanged, and the power flow calculation is performed on the exchanged line based on the accessed new energy data, and the operation mode of the distribution network after the access to the new energy data is adjusted until the various operation status data obtained by the power flow calculation meet the constraint conditions; If the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met, the photovoltaic reverse transmission over-limit line is adjusted according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy.

[0006] Further, the acquiring of the target analysis object in the distribution network connected to the new energy data, and searching for the photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object, comprises: Obtaining each main transformer and each feeder in the distribution network after accessing the new energy data, and determining each main transformer and each feeder as the target analysis object; The load rate of the target analysis object is calculated, and the photovoltaic reverse transmission over-limit line is determined according to the load rate of the target analysis object.

[0007] Furthermore, the calculating of the load rate of the target analysis object and determining the photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object include: Calculate the load rate of the main transformer according to the maximum load of the main transformer after the new energy data is connected and the maximum load capacity of the main transformer itself; Calculate the load rate of the feeder according to the maximum load of the feeder after accessing the new energy data and its own maximum capacity; The photovoltaic reverse transmission over-limit line existing in the distribution network is determined according to the load rate of each of the main transformers and the load rate of each of the feeders.

[0008] Furthermore, the branch exchange of the main line of the photovoltaic reverse transmission over-limit line and the flow calculation of the exchanged line based on the accessed new energy data are performed, and the operation mode of the distribution network after the access to the new energy data is adjusted until the operation status data obtained by the flow calculation meet the constraint conditions, including: By using a branch exchange method based on heuristic rules, the branch exchange of the main line of the photovoltaic reverse transmission over-limit line is performed at least once, and the operation mode of the distribution network after accessing the new energy data is adjusted; Performing power flow calculation on the line of each branch exchange to obtain a plurality of operation status data; If all the operating status data satisfy the constraint conditions, the branch exchange is stopped; if at least one of the operating status data does not satisfy the constraint conditions, the branch exchange and operating status data comparison of the main line of the photovoltaic reverse transmission over-limit line are continued at least once.

[0009] Furthermore, the operating status data includes the voltage value of the node on the photovoltaic reverse transmission over-limit line and the main transformer capacity load ratio. After the step of performing power flow calculation on the line of each branch exchange to obtain a plurality of the operating status data, the method further includes: Compare the calculated voltage value of the node on the photovoltaic reverse transmission over-limit line and the main transformer capacity-load ratio with the constraint conditions, wherein the constraint conditions also include the node voltage constraint condition and the main transformer capacity-load ratio constraint condition; If the voltage value of the node on the photovoltaic reverse transmission over-limit line meets the node voltage constraint condition and the capacity load ratio of the main transformer on the photovoltaic reverse transmission over-limit line meets the main transformer capacity load ratio constraint condition, then it is judged that each of the operating status data obtained by the power flow calculation meets the constraint condition.

[0010] Further, the calling of the day-ahead scenario analysis strategy or the intraday scenario analysis strategy to adjust the photovoltaic reverse transmission over-limit line includes: Determining whether the access scenario of the new energy data is the day-ahead scenario or the intra-day scenario; If the access scenario of the new energy data is the day-ahead scenario, an over-limit adjustment is performed based on the day-ahead scenario analysis strategy, including calculating forecast data for determining the user's next-day electricity consumption adjustment strategy based on the user's off-peak electricity consumption data, and adjusting the user's next-day electricity consumption based on the forecast data; If the access scenario of the new energy data is the intraday scenario, over-limit adjustment is performed based on the intraday scenario analysis strategy, including limiting the photovoltaic output according to the real-time data of the distributed power output connected to the distribution network.

[0011] Further, after the step of calling the day-ahead scenario analysis strategy or the intraday scenario analysis strategy to adjust the photovoltaic reverse transmission over-limit line, the method further includes: The adjustment strategy adjustment corresponding to the day-ahead scenario or the intraday scenario is displayed in a visual manner, and the control result of the photovoltaic reverse transmission over-limit line is written into a real-time database.

[0012] In a second aspect, an embodiment of the present invention further provides a photovoltaic reverse transmission over-limit control device based on new energy access, the device comprising: A data acquisition module, used to acquire new energy data, and divide power flow over-limit analysis decisions based on access scenarios of the new energy data, wherein the power flow over-limit analysis decisions include a day-ahead scenario analysis strategy for power flow analysis based on predicted data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on real-time data of the distribution network after accessing the new energy data; An over-limit route search module is used to obtain a target analysis object in the distribution network connected to the new energy data, and search for a photovoltaic reverse transmission over-limit route according to the load rate of the target analysis object; A power flow calculation module is used to exchange the branches of the main line of the photovoltaic reverse transmission over-limit line and perform power flow calculation on the exchanged line based on the accessed new energy data, and adjust the operation mode of the distribution network after accessing the new energy data until the various operating status data obtained by the power flow calculation meet the constraint conditions; The over-limit processing module is used to adjust the photovoltaic reverse transmission over-limit line according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy if the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met.

[0013] In the third aspect, an embodiment of the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the photovoltaic reverse transmission over-limit control method based on new energy access as described in the first aspect are implemented.

[0014] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the photovoltaic reverse transmission over-limit control method based on new energy access as described in the first aspect are implemented.

[0015] The beneficial effects achieved by the present invention are as follows: after the distribution network is connected to the new energy data, the problem of power flow exceeding the limit is solved by comprehensively considering the adjustment of the operation mode of the distribution network and combining the day-ahead scenario analysis strategy and the intraday scenario analysis strategy. The over-limit analysis and adjustment are carried out by combining the new energy itself and the operation mode of the distribution network. The data reliability is higher, and the photovoltaic reverse transmission over-limit line can be determined more accurately and the power flow calculation can be performed. The more accurate the calculation result is, the more accurate the final control result is, which is more conducive to improving the control ability of the power flow exceeding the limit of the distribution network, ensuring the safe and stable operation of the distribution network, and reducing the failures and losses caused by the power flow exceeding the limit; the power flow exceeding limit analysis decision is divided into two scenarios of day-ahead and intraday according to the new energy data access scenario, and the corresponding strategy is selected according to the access scenario to perform over-limit adjustment, and the real-time data and the predicted data are fully used for over-limit analysis and decision; the branches of the main line are exchanged for the photovoltaic reverse transmission over-limit line, and the power flow calculation and constraint condition analysis are performed, so as to realize the operation mode adjustment of the distribution network, and the appropriate branch exchange scheme can be quickly found to improve the adjustment efficiency of the operation mode.

[0016] The above invention content is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings. The drawings are only for the purpose of illustrating preferred embodiments and are not to be considered as limiting the present invention. Also, the same reference symbols are used throughout the drawings to represent the same parts.

[0018] Figure 1 It is a flow chart of a photovoltaic reverse transmission over-limit control method based on new energy access provided by an embodiment of the present invention.

[0019] Figure 2 It is a structural schematic diagram of a photovoltaic reverse transmission over-limit control device based on new energy access provided by an embodiment of the present invention.

[0020] Figure 3 A schematic diagram of the structure of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the operations (or steps) as sequential processes, many of the operations (or steps) therein can be implemented in parallel, concurrently, or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the drawings; the process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0023] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. It should also be understood that in various embodiments of the present invention, the size of the sequence number of each process does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0024] It should be understood that, in the present invention, "multiple" refers to two or more than two. "And / or" is merely a variable relationship that describes associated objects, indicating that three relationships may exist. "Including A, B and C" means that A, B and C are all included, "Including A, B or C" means that one of A, B and C is included, and "Including A, B and / or C" means that any one or any two or three of A, B and C are included. In the present invention, "B corresponding to A", "B corresponding to A", "A corresponds to B" or "B corresponds to A" means that B is associated with A, and B can be determined based on A. Determining B based on A does not mean that B is determined only based on A, but B can also be determined based on A and / or other information.

[0025] Embodiment 1 Please refer to Figure 1 , Figure 1 The flowchart of the photovoltaic reverse transmission over-limit control method based on new energy access provided by an embodiment of the present invention is a flowchart of the photovoltaic reverse transmission over-limit control method based on new energy access, which specifically includes the following steps: S1. Acquire new energy data, and divide power flow over-limit analysis decisions based on the access scenarios of the new energy data. The power flow over-limit analysis decisions include a day-ahead scenario analysis strategy for power flow analysis based on the predicted data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on the real-time data of the distribution network after accessing the new energy data.

[0026] In the present invention, the photovoltaic reverse transmission over-limit control method based on new energy access is applicable to the application scenario where a large amount of new energy data is accessed to the distribution network. When a large amount of distributed new energy is accessed to the distribution network, the photovoltaic reverse transmission over-limit situation in the distribution network can be regulated by the photovoltaic reverse transmission over-limit control method based on new energy access provided by this application. Current over-limit refers to the phenomenon in the power system that the bus voltage, branch current or power of the transmission network exceeds its own rated value, resulting in line overload and possible equipment damage, power outages and other problems.

[0027] Among them, the electronic device running the photovoltaic reverse transmission over-limit control method based on new energy access can be a distribution automation master station. It should be pointed out that the electronic device running the photovoltaic reverse transmission over-limit control method based on new energy access can communicate with other electronic devices through wireless connection / wired connection. It should be pointed out that the above wireless connection method includes but is not limited to 3G / 4G / 5G connection, WiFi connection, Bluetooth connection, WiMAX connection, Zigbee connection, UWB connection, and other wireless connection methods currently known or to be developed in the future.

[0028] Among them, the new energy sources connected to the distribution network include but are not limited to distributed solar energy, geothermal energy, wind energy, ocean energy, biomass energy and nuclear fusion energy. Multiple new energy sources can be connected in a distribution network, that is, distributed power sources can be connected. After the distribution network is connected to the new energy, the new energy data can be obtained first, and the power flow over-limit analysis decision can be divided first according to the access scenario of the new energy data. Among them, the power flow over-limit analysis decision refers to the strategy used for over-limit adjustment. The power flow over-limit analysis decision includes the day-ahead scenario analysis strategy for power flow analysis based on the predicted data of the distribution network. The predicted data can refer to the data obtained by predicting the operation data of the distribution network in the previous period of time for a period of time in the future. The power flow over-limit analysis decision also includes the intraday scenario analysis strategy for power flow analysis based on the real-time data of the distribution network after the access to the new energy data. For example: When it is a day-ahead scenario, the load over-limit situation and photovoltaic power generation situation are predicted based on tomorrow's weather and typical curves to obtain forecast data. When it is an intraday scenario, the operating data of the main transformer (main transformer) and the line are monitored in real time to obtain real-time data. The forecast data or real-time data is analyzed. When the forecast data or real-time data of the equipment or line exceeds the corresponding threshold, it is determined that there is a photovoltaic reverse transmission over-limit, and then the load transfer strategy is analyzed to screen and generate the optimal day-ahead scenario analysis strategy for load transfer under power flow over-limit or the intraday scenario analysis strategy for photovoltaic output.

[0029] According to the above-mentioned new energy data access scenario, the power flow over-limit analysis decision is divided into two scenarios: day-ahead and intra-day, which is more conducive to making full use of real-time data and forecast data for data analysis and strategy formulation.

[0030] S2. Acquire a target analysis object in the distribution network connected to the new energy data, and search for a photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object.

[0031] Specifically, for the distribution network connected to the new energy data, in order to perform over-limit analysis, we can first determine the object that needs to be analyzed, that is, the target analysis object, and then calculate the load rate of the target analysis object, and then find the photovoltaic reverse transmission over-limit line in the distribution network according to the load rate.

[0032] Specifically, step S2 includes: S21, acquiring each main transformer and each feeder in the distribution network after accessing the new energy data, and determining each main transformer and each feeder as the target analysis object; S22, calculating the load rate of the target analysis object, and determining the photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object.

[0033] Specifically, considering that the main electrical equipment that affects the maximum power supply capacity of the distribution network is the feeder and the main transformer, in order to improve the accuracy of over-limit judgment, the main transformer and feeder in the distribution network connected to the new energy data can be used as the target analysis objects for over-limit analysis. For each target analysis object, by calculating the load rate, and then comparing the load rate with the preset load rate threshold, the line corresponding to the load rate threshold exceeding the load rate threshold is determined as the photovoltaic reverse transmission over-limit line.

[0034] More specifically, the above step S22 includes: S221, calculating the load rate of the main transformer according to the maximum load of the main transformer after the new energy data is connected and the maximum load capacity of the main transformer itself; S222, calculating the load rate of the feeder according to the maximum load of the feeder after accessing the new energy data and its own maximum capacity; S223. Determine the photovoltaic reverse transmission over-limit line existing in the distribution network according to the load rate of each of the main transformers and the load rate of each of the feeders.

[0035] The load rate of the main transformer and feeder after accessing the new energy data can be calculated based on the following formula (1): Where η is the load rate, P a Indicates the maximum load of the main transformer or feeder, P b Indicates the maximum load capacity of the main transformer or feeder itself.

[0036] The load rate threshold of the above-mentioned main transformer may be different from the load rate threshold of the feeder. Setting the load rate threshold based on different devices is more targeted, which is conducive to the accuracy of judging the load rate of different devices. The preset load rate threshold may include an upper limit threshold of the load rate and a lower limit threshold of the load rate. By comparing the calculated load rate of each main transformer and feeder with the corresponding upper limit threshold of the load rate and the lower limit threshold of the load rate, it is determined whether the load rate of each main transformer and feeder is within the range of the upper limit threshold of the load rate and the lower limit threshold of the load rate set for similar devices. If it is within the range, it can be indicated that there is no photovoltaic reverse transmission over-limit in the line where the main transformer and / or feeder are located; if the load rate is lower than the lower limit threshold of the load rate, it is determined that there is photovoltaic reverse transmission over-limit, and the line where the main transformer and / or feeder are located is a photovoltaic reverse transmission over-limit line.

[0037] After accessing the new energy data, the corresponding load rates are calculated by first taking the main transformer and feeder that affect the maximum power supply capacity of the distribution network as the target analysis objects, and analyzing the photovoltaic reverse transmission line in the load rate circuit, which can improve the judgment accuracy of the photovoltaic reverse transmission line.

[0038] S3. For the photovoltaic reverse transmission over-limit line, the branches of the trunk line are exchanged and the power flow calculation is performed on the exchanged line based on the connected new energy data, and the operation mode of the distribution network is adjusted after the new energy data is connected, until the operation status data obtained by the power flow calculation meets the constraint conditions.

[0039] Among them, for photovoltaic reverse transmission over-limit lines, we first consider adjusting the operation mode of the distribution network after accessing the new energy data, by exchanging the branches of the main line for the photovoltaic reverse transmission over-limit lines at least once, and performing a local topology analysis each time, and performing power flow calculation based on the topology analysis, and comparing the operating status data obtained according to the power flow calculation results with the constraint conditions.

[0040] It is important to know that the above power flow calculation is to determine the calculation of steady-state operating parameters of each part of the power system based on the given grid structure, parameters and operating conditions of generators, loads and other components. Usually, the given operating conditions include the power of each power source and load point in the system, the voltage of the hub point, the voltage and phase angle of the balance point. The operating status data to be calculated include the voltage amplitude, capacity load factor, phase angle of each bus node of the power grid, the power distribution of each branch, power loss, etc.

[0041] Specifically, the above step S3 includes: S31, performing at least one branch exchange of the main line of the photovoltaic reverse transmission over-limit line through a branch exchange method based on heuristic rules, and adjusting the operation mode of the distribution network after accessing the new energy data; S32, performing power flow calculation on the line of each branch exchange to obtain a plurality of operation status data; S33. If all the operating status data satisfy the constraint conditions, stop the branch exchange. If at least one of the operating status data does not satisfy the constraint conditions, continue to perform at least one branch exchange and operating status data comparison on the main line of the photovoltaic reverse transmission over-limit line.

[0042] Among them, the branch exchange method is an algorithm for distribution network reconstruction, also known as the switch exchange algorithm. The basic idea is to use switches to switch loads between two feeders to achieve load balancing and reduce distribution network losses. The branch exchange method uses heuristic rules to narrow the range of switch combinations that need to be considered on the photovoltaic reverse transmission over-limit line, and quickly obtains the result of reducing the distribution network line loss.

[0043] More specifically, each time a branch exchange is performed, a flow calculation is performed correspondingly. Through the flow calculation, the voltage value of the corresponding node on the line, the capacity load ratio of the main converter, the active power, the reactive power and other operating status data can be calculated. Each operating status data is compared with the constraint conditions to determine whether the constraint conditions are met. According to the branch conversion line that meets the constraint conditions, the operating mode of the distribution network after accessing the new energy data is adjusted, including adjusting the switch equipment and knife switch equipment in the line. If there is at least one operating status data that does not meet the constraint conditions, the branch exchange and flow calculation of the trunk line will continue, and the operating mode of the distribution network will be adjusted according to each branch exchange.

[0044] More specifically, after step S32, the method further includes the steps of: S34, comparing the calculated voltage value of the node on the photovoltaic reverse transmission over-limit line and the main transformer capacity-load ratio with the constraint conditions, wherein the constraint conditions also include the node voltage constraint condition and the main transformer capacity-load ratio constraint condition; S35. If the voltage value of the node on the photovoltaic reverse transmission over-limit line meets the node voltage constraint condition and the capacity-load ratio of the main transformer on the photovoltaic reverse transmission over-limit line meets the main transformer capacity-load ratio constraint condition, then it is determined that each of the operating status data obtained by the power flow calculation meets the constraint condition.

[0045] Specifically, the above-mentioned main transformer capacity-load ratio refers to the ratio of the main transformer capacity to the maximum operating load of the area it is responsible for. It is used to reflect the load that this transformer can bear when fully loaded when other main transformers in the area cannot be put into use for some reason. It can indicate the accident guarantee rate of the distribution network system in the area.

[0046] In this embodiment, the operating status data obtained by each power flow calculation includes the voltage value of the node on the photovoltaic reverse transmission over-limit line and the load ratio of the main transformer. The node voltage constraint condition is compared with the calculated node voltage value, and the main transformer load ratio constraint condition is compared with the calculated main transformer load ratio, and the operation mode of the distribution network is adjusted according to the comparison result. For example, if the calculated voltage value of the node on the photovoltaic reverse transmission over-limit line is 120KV, the node voltage constraint condition is 110KV, the calculated main transformer load ratio is 1.3, and the main transformer load ratio constraint condition is 1.1, it means that the node voltage constraint condition and the main transformer load ratio constraint condition are not met.

[0047] The above-mentioned branch exchange method using heuristic rule search to adjust the operation mode of the distribution network can quickly find a suitable branch exchange plan and improve the efficiency of the operation mode adjustment; by calculating the corresponding operating status data and comparing it with the node voltage constraint conditions and the main transformer capacity load ratio constraint conditions, it can be judged whether the power flow calculation after the branch exchange has achieved over-limit adjustment and reduced to the safety range of the line, and the above-mentioned power flow over-limit safety control is carried out in combination with the operation mode of the distribution network, which improves the safe and stable operation of the distribution network and reduces failures and losses caused by power flow over-limit.

[0048] S4. If the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met, adjust the photovoltaic reverse transmission over-limit line according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy.

[0049] When the operation mode of the distribution network is adjusted after access to new energy data, the photovoltaic reverse transmission over-limit situation in the distribution network still exists. In this case, the photovoltaic reverse transmission over-limit situation of the photovoltaic reverse transmission over-limit line is adjusted through the day-ahead scenario analysis strategy or the intraday scenario analysis strategy.

[0050] Specifically, the above step S4 includes: S41, determining whether the access scenario of the new energy data is the day-ahead scenario or the day-intraday scenario; S42: If the access scenario of the new energy data is the day-ahead scenario, performing over-limit adjustment based on the day-ahead scenario analysis strategy, including calculating prediction data for determining the user's next-day electricity consumption adjustment strategy based on the user's off-peak electricity consumption data, and performing the user's next-day electricity consumption adjustment based on the prediction data; S43: If the access scenario of the new energy data is the intraday scenario, an over-limit adjustment is performed based on the intraday scenario analysis strategy, including limiting the photovoltaic output according to the real-time data of the distributed power output connected to the distribution network.

[0051] Specifically, the access scenario of new energy data can be judged and the corresponding analysis strategy can be selected to control the over-limit situation of photovoltaic reverse transmission. Among them, when it is a day-ahead scenario, future prediction is made based on the off-peak power consumption data of users in the distribution network. Specifically, the above-mentioned user's next-day power consumption adjustment strategy determined based on the user's off-peak power consumption data can be based on the Minty algorithm or uniformity network theory, iterative training of historical compliance characteristic curve data, and formulating strategies for line over-limit adjustment in combination with future weather trends. For example, the historical load characteristic curve data of the past week is used as the input of the Minty (interior point method) algorithm to determine a feasible domain, and iterate through the Minty algorithm based on the feasible domain until the optimal solution is found. Finally, according to the optimal solution and the weather data of the next week, the over-limit situation and photovoltaic power generation situation of the next week are predicted, and the over-limit is adjusted according to the predicted situation. Among them, the user's off-peak power consumption data refers to the staggered power consumption during the peak power consumption period. Off-peak power consumption refers to the transfer of part of the load during the peak power consumption period of the power grid to the off-peak power consumption period according to the load characteristics of the power grid, thereby reducing the peak-valley load difference of the power grid, optimizing resource allocation, and improving the safety and economy of the power grid.

[0052] Possibly, after step S4, the method further comprises: S5. Display the adjustment strategy corresponding to the day-ahead scenario or the intraday scenario in a visual manner, and write the control result of the photovoltaic reverse transmission line that exceeds the limit into a real-time database.

[0053] Specifically, the selected adjustment strategy can be visualized through the display interface of the electronic device that runs the photovoltaic reverse transmission over-limit control method based on new energy access, so as to more intuitively understand the adjustment strategy for users to view and execute. The various data of the adjusted line can also be displayed to more intuitively obtain the control results after the over-limit adjustment, and at the same time, the control results of the photovoltaic reverse transmission over-limit line are written into the real-time database, where the real-time database is a database established using a real-time data model, which is used to process continuously updated rapidly changing data and time-limited transaction processing, and is mainly used in industrial monitoring, such as: data monitoring in industrial fields such as electricity, petrochemicals, chemicals, and steel.

[0054] In the embodiment of the present invention, the problem of power flow over-limit is solved by comprehensively considering various strategies such as operation mode adjustment, DG output control, and user peak power consumption, which can effectively improve the safe and stable operation of the distribution network and the absorption efficiency of DG; according to the new energy data access scenario, the power flow over-limit analysis decision is divided into two scenarios: day-ahead and day-intraday, and the corresponding strategy is selected according to the access scenario for over-limit adjustment, making full use of real-time data and predicted data for analysis and decision-making; the above-mentioned branch exchange method using heuristic rule search to adjust the operation mode of the distribution network can quickly find a suitable branch exchange scheme and improve the efficiency of operation mode adjustment. The above-mentioned effective power flow over-limit safety control improves the safe and stable operation of the distribution network and reduces failures and losses caused by power flow over-limit. In addition, the above-mentioned method is applicable to various new energy data access scenarios and has strong universality and practicality.

[0055] Embodiment 2 refer to Figure 2 As shown, Figure 2 A schematic diagram of a photovoltaic reverse transmission over-limit control device based on new energy access is provided for an embodiment of the present invention. The device M20 includes: The data acquisition module M201 is used to acquire new energy data and divide the power flow over-limit analysis decision based on the access scenario of the new energy data. The power flow over-limit analysis decision includes a day-ahead scenario analysis strategy for power flow analysis based on the predicted data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on the real-time data of the distribution network after accessing the new energy data; The over-limit route search module M202 is used to obtain a target analysis object in the distribution network connected to the new energy data, and search for a photovoltaic reverse transmission over-limit route according to the load rate of the target analysis object; The power flow calculation module M203 is used to exchange the branches of the trunk line of the photovoltaic reverse transmission over-limit line and perform power flow calculation on the exchanged line based on the accessed new energy data, and adjust the operation mode of the distribution network after accessing the new energy data until the operation status data obtained by the power flow calculation meet the constraint conditions; The over-limit processing module M204 is used to adjust the photovoltaic reverse transmission over-limit line according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy if the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met.

[0056] The photovoltaic reverse transmission over-limit control device based on new energy access provided by the embodiment of the present invention can implement each process in the photovoltaic reverse transmission over-limit control method based on new energy access, and can achieve the same beneficial effects. To avoid repetition, it will not be repeated here.

[0057] The embodiment of the present invention also provides a computer device, please refer to Figure 3 , Figure 3 : is a structural diagram of a computer device provided in an embodiment of the present invention, and the computer device D30 includes: a processor D301, a memory D302, and a computer program stored in the memory D302 and executable on the processor D301. The processor D301 calls the computer program stored in the memory D302 to execute each step of the photovoltaic reverse transmission over-limit control method based on new energy access provided in an embodiment of the present invention, and can achieve the same technical effect, refer to the description in the above embodiment, and will not be repeated here.

[0058] It should be pointed out that those skilled in the art can understand that the electronic device in the embodiment of the present invention is a device that can automatically perform numerical calculations and / or information processing according to pre-set or stored instructions, and its hardware includes but is not limited to microprocessors, application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), digital signal processors (DSP), embedded devices, etc. The electronic device can be a computing device such as a desktop computer, a notebook, a handheld computer, and a cloud server. The electronic device can perform human-computer interaction through a keyboard, a mouse, a remote control, a touchpad, or a voice-controlled device.

[0059] An embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes and steps in the photovoltaic reverse transmission over-limit control method based on new energy access provided by the embodiment of the present invention are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0060] It should be noted that the readable storage medium includes flash memory, hard disk, multimedia card, card-type memory (for example, SD or DX memory, etc.), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, etc. In some embodiments, the memory may be an internal storage unit of an electronic device, such as a hard disk or memory of the electronic device. In other embodiments, the memory may also be an external storage device of an electronic device, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device. Of course, the memory may also include both the internal storage unit of the electronic device and its external storage device. In this embodiment, the memory is generally used to store operating devices and various application software installed in the electronic device, such as program codes of photovoltaic reverse transmission over-limit control methods based on new energy access, etc. In addition, the memory may also be used to temporarily store various types of data that have been output or are to be output.

[0061] A person of ordinary skill in the art can understand that all or part of the processes in the photovoltaic reverse transmission over-limit control method based on new energy access in the above-mentioned embodiment can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of various embodiments of the photovoltaic reverse transmission over-limit control method based on new energy access.

[0062] The specific implementation method described above is a preferred implementation method of the photovoltaic reverse transmission over-limit control method based on new energy access of the present invention, and it is not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to this specific implementation method. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A photovoltaic reverse transmission over-limit control method based on new energy access, characterized in that: The following steps are involved: Acquire new energy data, and divide power flow over-limit analysis decisions based on access scenarios of the new energy data, wherein the power flow over-limit analysis decisions include a day-ahead scenario analysis strategy for power flow analysis based on forecast data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on real-time data of the distribution network after access to the new energy data; Acquire a target analysis object in the distribution network connected to the new energy data, and search for a photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object; For the photovoltaic reverse transmission over-limit line, the branch line of the trunk line is exchanged, and the power flow calculation is performed on the exchanged line based on the accessed new energy data, and the operation mode of the distribution network after the access to the new energy data is adjusted until the various operation status data obtained by the power flow calculation meet the constraint conditions; If the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met, the photovoltaic reverse transmission over-limit line is adjusted according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy.

2. The photovoltaic reverse transmission over-limit control method based on new energy access according to claim 1 is characterized in that: The step of acquiring a target analysis object in a distribution network connected to the new energy data and searching for a photovoltaic reverse transmission over-limit line according to a load rate of the target analysis object includes: Obtaining each main transformer and each feeder in the distribution network after accessing the new energy data, and determining each main transformer and each feeder as the target analysis object; The load rate of the target analysis object is calculated, and the photovoltaic reverse transmission over-limit line is determined according to the load rate of the target analysis object.

3. The photovoltaic reverse transmission over-limit control method based on new energy access according to claim 2 is characterized in that: The calculating the load rate of the target analysis object and determining the photovoltaic reverse transmission over-limit line according to the load rate of the target analysis object includes: Calculate the load rate of the main transformer according to the maximum load of the main transformer after the new energy data is connected and the maximum load capacity of the main transformer itself; Calculate the load rate of the feeder according to the maximum load of the feeder after accessing the new energy data and its own maximum capacity; The photovoltaic reverse transmission over-limit line existing in the distribution network is determined according to the load rate of each of the main transformers and the load rate of each of the feeders.

4. The photovoltaic reverse transmission over-limit control method based on new energy access according to claim 1 is characterized in that: The branch switching of the trunk line for the photovoltaic reverse transmission over-limit line and the flow calculation of the switched line based on the accessed new energy data, and the operation mode of the distribution network after accessing the new energy data, until the operation status data obtained by the flow calculation meet the constraint conditions, include: By using a branch exchange method based on heuristic rules, the branch exchange of the main line of the photovoltaic reverse transmission over-limit line is performed at least once, and the operation mode of the distribution network after accessing the new energy data is adjusted; Performing power flow calculation on the line of each branch exchange to obtain a plurality of operation status data; If all the operating status data satisfy the constraint conditions, the branch exchange is stopped; if at least one of the operating status data does not satisfy the constraint conditions, the branch exchange and operating status data comparison of the main line of the photovoltaic reverse transmission over-limit line are continued at least once.

5. The photovoltaic reverse transmission over-limit control method based on new energy access according to claim 4 is characterized in that: The operation status data includes the voltage value of the node on the photovoltaic reverse transmission over-limit line and the capacity load ratio of the main transformer. After the step of performing power flow calculation on the line of each branch exchange to obtain a plurality of the operation status data, the step further includes: Compare the calculated voltage value of the node on the photovoltaic reverse transmission over-limit line and the main transformer capacity-load ratio with the constraint conditions, wherein the constraint conditions also include the node voltage constraint condition and the main transformer capacity-load ratio constraint condition; If the voltage value of the node on the photovoltaic reverse transmission over-limit line meets the node voltage constraint condition and the capacity load ratio of the main transformer on the photovoltaic reverse transmission over-limit line meets the main transformer capacity load ratio constraint condition, then it is judged that each of the operating status data obtained by the power flow calculation meets the constraint condition.

6. The photovoltaic reverse transmission over-limit control method based on new energy access according to claim 5 is characterized in that: The calling of the day-ahead scenario analysis strategy or the intraday scenario analysis strategy to adjust the photovoltaic reverse transmission over-limit line includes: Determining whether the access scenario of the new energy data is the day-ahead scenario or the intra-day scenario; If the access scenario of the new energy data is the day-ahead scenario, an over-limit adjustment is performed based on the day-ahead scenario analysis strategy, including calculating forecast data for determining the user's next-day electricity consumption adjustment strategy based on the user's off-peak electricity consumption data, and adjusting the user's next-day electricity consumption based on the forecast data; If the access scenario of the new energy data is the intraday scenario, over-limit adjustment is performed based on the intraday scenario analysis strategy, including limiting the photovoltaic output according to the real-time data of the distributed power output connected to the distribution network.

7. The photovoltaic reverse transmission over-limit control method based on new energy access according to any one of claims 1 to 6, characterized in that: After the step of calling the day-ahead scenario analysis strategy or the intraday scenario analysis strategy to adjust the photovoltaic reverse transmission over-limit line, the method further includes: The adjustment strategy adjustment corresponding to the day-ahead scenario or the intraday scenario is displayed in a visual manner, and the control result of the photovoltaic reverse transmission over-limit line is written into a real-time database.

8. A photovoltaic reverse transmission over-limit control device based on new energy access, characterized in that: The device comprises: A data acquisition module, used to acquire new energy data, and divide power flow over-limit analysis decisions based on access scenarios of the new energy data, wherein the power flow over-limit analysis decisions include a day-ahead scenario analysis strategy for power flow analysis based on predicted data of the distribution network and an intraday scenario analysis strategy for power flow analysis based on real-time data of the distribution network after accessing the new energy data; An over-limit route search module is used to obtain a target analysis object in the distribution network connected to the new energy data, and search for a photovoltaic reverse transmission over-limit route according to the load rate of the target analysis object; A power flow calculation module is used to exchange the branches of the main line of the photovoltaic reverse transmission over-limit line and perform power flow calculation on the exchanged line based on the accessed new energy data, and adjust the operation mode of the distribution network after accessing the new energy data until the various operating status data obtained by the power flow calculation meet the constraint conditions; The over-limit processing module is used to adjust the photovoltaic reverse transmission over-limit line according to the day-ahead scenario analysis strategy or the intra-day scenario analysis strategy if the photovoltaic reverse transmission over-limit line still exists in the distribution network after the constraint condition is met.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the photovoltaic reverse transmission over-limit control method based on new energy access are implemented as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, the steps of the photovoltaic reverse transmission over-limit control method based on new energy access are implemented as described in any one of claims 1 to 7.

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