Source load storage power grid structure and overvoltage treatment method

Abstract

This invention relates to the field of distributed grid control technology, and more particularly to a source-load-storage grid structure and overvoltage mitigation method. The method first obtains the bus voltage; then, based on the bus voltage and a predetermined voltage range, it iterates between identifying multiple target load feeders and adjusting the output of multiple target distributed power sources to balance the voltage of the multiple load lines. In this embodiment, the method iteratively adjusts the voltage of multiple load feeders in the source-load-storage grid by finding target load feeders that exceed a predetermined voltage range and adjusting the distributed power sources affecting those feeders, thereby stabilizing the voltage in the distributed grid. Since this method determines the target distributed power sources based on the influence of distributed power source output on the load feeder voltage, it is unaffected by the grid structure and, compared to methods using topology analysis, requires less computation and has a faster response.

Description

Technical Field

[0001] This invention relates to the field of distributed power grid control technology, and in particular to a source-load-storage power grid structure and an overvoltage mitigation method. Background Technology

[0002] Renewable energy power generation has become a development trend, and distributed generation is an important form of renewable energy power generation.

[0003] The large-scale integration of distributed photovoltaic (PV) power sources with high penetration rates has rendered traditional distribution network operation and control methods ineffective. Distributed grids have altered the power flow distribution and direction of traditional distribution networks, and these changes have a significant impact on the steady-state voltage distribution of the grid. One such impact is the generation of overvoltages at certain nodes in the distribution network, which prevents distributed PV power sources from being properly integrated into the distribution network.

[0004] Therefore, it is necessary to develop and design a method for managing overvoltage in distributed power grids. Summary of the Invention

[0005] The present invention provides a source-load-storage grid structure and an overvoltage mitigation method to address the problem that overvoltage issues caused by distributed access to the distribution grid are not easily mitigated in the prior art.

[0006] In a first aspect, embodiments of the present invention provide a method for managing overvoltage in a distributed power grid, comprising:

[0007] Obtain the bus voltage, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through the load feeder, and the bus voltage is the voltage at the main power supply terminal of the bus;

[0008] Based on the bus voltage and a predetermined voltage range, the voltage of the multiple load lines is balanced by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources. The target load feeders are load feeders whose voltage exceeds the predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders.

[0009] In one possible implementation, balancing the voltage of the multiple load lines by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources, based on the bus voltage and a predetermined voltage range, includes:

[0010] Target load feeder determination steps: Based on the bus voltage and the predetermined voltage range, determine multiple target load feeders;

[0011] Based on the multiple grid-connected current datasets and the multiple load current datasets, multiple target distributed power sources are determined, wherein the multiple grid-connected current datasets correspond to multiple distributed power sources, and the multiple load current datasets are obtained based on multiple target load feeders;

[0012] The output of the multiple target distributed power sources is adjusted according to the influence coefficients of the multiple target load feeders.

[0013] Based on the bus voltage and the predetermined voltage range, check the voltage of the plurality of load feeders. If the voltage of the plurality of load feeders exceeds the predetermined range, proceed to the target load feeder determination step.

[0014] In one possible implementation, determining multiple target distributed power sources based on the multiple grid-connected current datasets and the multiple load current datasets includes:

[0015] Acquire multiple voltage sampling data of the busbar;

[0016] Based on the multiple voltage sampling data, the fundamental frequency and fundamental phase of the bus voltage are determined;

[0017] Based on the fundamental frequency, the fundamental phase, and the first formula, each of the plurality of grid-connected current datasets and the plurality of load current datasets is extracted to obtain a plurality of grid-connected feature datasets and a plurality of load feature datasets, wherein the first formula is:

[0018]

[0019] In the formula, Feature(n) is the nth feature data in the feature dataset, I(n) is the nth data in the current dataset, I(max) is the maximum value of the current data in the current dataset, cos() is the cosine function, ω0 is the fundamental frequency, N is the number of samples of current data within the fundamental period, and α is the fundamental phase.

[0020] For each target load feeder, multiple target distributed power sources are determined based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets.

[0021] In one possible implementation, determining multiple target distributed power sources for each target load feeder based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets includes:

[0022] Based on the second formula, the load characteristic dataset of the corresponding target load feeder, and the multiple grid-connected characteristic datasets, the correlation coefficients between multiple distributed power sources and the target load feeder are determined, wherein the second formula is:

[0023]

[0024] In the formula, P ij The correlation coefficient between the i-th distributed power source and the j-th target load feeder. i (n) represents the nth data point in the i-th load feature dataset. j (n) represents the nth data point of the jth grid-connected characteristic dataset, and N is the total number of data points in the characteristic dataset;

[0025] Multiple distributed power sources whose absolute values ​​of correlation coefficients are greater than a threshold are selected as the multiple target distributed power sources.

[0026] In one possible implementation, determining the fundamental frequency and fundamental phase of the bus voltage based on the plurality of voltage sampling data includes:

[0027] The multiple voltage sampling data are extracted sequentially and accumulated until the sum is less than the threshold.

[0028] Obtain the sampling duration corresponding to the extracted multiple sampled data, and use it as the period of the fundamental frequency;

[0029] The frequency of the fundamental wave is determined based on its period.

[0030] Substituting multiple undetermined phase angles and the extracted sampled data into the third formula, multiple phase angle coefficients are obtained, wherein the third formula is:

[0031]

[0032] In the formula, w k Let U(m) be the k-th phase angle coefficient, U(m) be the m-th data point among the multiple sampled data points, M be the total number of sampled data points, ω0 be the fundamental frequency, cos(ω) be the cosine function, and α be the sine function. k This is the k-th undetermined phase angle;

[0033] The undetermined phase angle corresponding to the phase angle coefficient with the largest value is selected as the fundamental phase.

[0034] In one possible implementation, adjusting the output of the plurality of target distributed power sources based on their influence coefficients on the plurality of target load feeders includes:

[0035] Based on the influence coefficients of the multiple target distributed power sources on the multiple target load feeders and the fourth formula, the grid connection voltage of the multiple target distributed power sources is adjusted, wherein the fourth formula is:

[0036]

[0037] In the formula, U′ i Let γ be the grid-connected voltage after adjustment for the i-th target distributed power source, γ be the adjustment coefficient, and P be the total number of target load feeders affected by the i-th target distributed power source. ij U is the correlation coefficient between the i-th distributed power source and the j-th target load feeder. i The grid-connected voltage before adjustment for the i-th target distributed power source.

[0038] Secondly, embodiments of the present invention provide a source-load-storage grid structure, including:

[0039] Busbars, pipe ends, multiple distributed power supply feeder lines, multiple load feeders, and multiple edge ends;

[0040] The distributed power feeder line includes: a power feeder and a distributed power source, wherein the distributed power source is connected to the bus through the power feeder; the distributed power source includes: a power generation device and an energy storage device, wherein the power generation device generates electricity according to the output indication and / or stores electrical energy in the energy storage device; the first end of the load feeder is electrically connected to the bus.

[0041] The plurality of edge terminals are configured to communicate with the pipe end, and the plurality of edge terminals are used to collect the voltage and current of the plurality of distributed power supply feeder lines and the plurality of load feeder lines;

[0042] The terminal outputs an indication to adjust the output of the distributed power source based on the access voltage of the bus, the voltage and current of the multiple distributed power source feeder lines and the multiple load lines, and iteratively balances the voltage of the multiple load lines.

[0043] Thirdly, embodiments of the present invention provide a distributed power grid overvoltage mitigation device for implementing the distributed power grid overvoltage mitigation method as described in the first aspect or any possible implementation thereof, the distributed power grid overvoltage mitigation device comprising:

[0044] A bus voltage acquisition module is used to acquire the bus voltage, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through a load feeder, and the bus voltage is the voltage at the main power supply terminal of the bus;

[0045] as well as,

[0046] The iterative balancing module is used to balance the voltage of the multiple load lines by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources based on the bus voltage and a predetermined voltage range. The target load feeders are load feeders whose voltage exceeds the predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders.

[0047] Fourthly, embodiments of the present invention provide a terminal, including a memory and a processor, wherein the memory stores a computer program executable on the processor, and the processor executes the computer program to implement the steps of the method as described in the first aspect or any possible implementation of the first aspect.

[0048] Fifthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method as described in the first aspect or any possible implementation thereof.

[0049] The beneficial effects of the embodiments of the present invention compared with the prior art are as follows:

[0050] This invention discloses a method for managing overvoltage in a distributed power grid. First, it obtains the bus voltage, where multiple distributed power sources are connected to the bus for grid-connected generation, and loads are connected to the bus via load feeders. The bus voltage is the voltage at the main power source terminal of the bus. Then, based on the bus voltage and a predetermined voltage range, it iterates between identifying multiple target load feeders and adjusting the output of multiple target distributed power sources to balance the voltage of the multiple load lines. The target load feeders are those whose voltage exceeds the predetermined range, and the target distributed power sources are those whose output affects the voltage of the target load feeders. This invention uses an iterative approach of finding target load feeders exceeding the predetermined voltage range and adjusting the distributed power sources affecting them to adjust the voltage of multiple load feeders in a source-load-storage power grid, thereby stabilizing the voltage in the distributed power grid. Because this method determines the target distributed power sources based on the influence of distributed power source output on load feeder voltage, it is unaffected by the grid structure and has a lower computational load and faster response compared to methods based on topology analysis. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a flowchart of the distributed power grid overvoltage mitigation method provided in the embodiments of the present invention;

[0053] Figure 2 This is a schematic diagram of the source-load-storage power grid structure provided by an embodiment of the present invention;

[0054] Figure 3 This is a functional block diagram of the distributed power grid overvoltage control device provided in the embodiments of the present invention;

[0055] Figure 4 This is a terminal function block diagram provided by an embodiment of the present invention. Detailed Implementation

[0056] In the following description, specific details such as particular system structures and techniques are set forth for illustrative purposes and not for limitation, so as to provide a thorough understanding of embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0057] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0058] The embodiments of the present invention will be described in detail below. This example is implemented based on the technical solution of the present invention, and provides detailed implementation methods and specific operation processes. However, the protection scope of the present invention is not limited to the following embodiments.

[0059] Figure 1 A flowchart of a distributed power grid overvoltage mitigation method provided for an embodiment of the present invention.

[0060] like Figure 1 As shown, a flowchart illustrating the implementation of the distributed power grid overvoltage mitigation method provided by an embodiment of the present invention is presented, and is described in detail below:

[0061] In step 101, the bus voltage is obtained, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through the load feeder. The bus voltage is the voltage at the main power supply terminal of the bus.

[0062] In step 102, based on the bus voltage and a predetermined voltage range, the voltage of the multiple load lines is balanced by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources. The target load feeders are load feeders whose voltage exceeds the predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders.

[0063] In some embodiments, step 102 includes: a target load feeder determination step: determining a plurality of target load feeders based on the bus voltage and a predetermined voltage range;

[0064] Based on the multiple grid-connected current datasets and the multiple load current datasets, multiple target distributed power sources are determined, wherein the multiple grid-connected current datasets correspond to multiple distributed power sources, and the multiple load current datasets are obtained based on multiple target load feeders;

[0065] The output of the multiple target distributed power sources is adjusted according to the influence coefficients of the multiple target load feeders.

[0066] Based on the bus voltage and the predetermined voltage range, check the voltage of the plurality of load feeders. If the voltage of the plurality of load feeders exceeds the predetermined range, proceed to the target load feeder determination step.

[0067] In some implementations, determining multiple target distributed power sources based on the multiple grid-connected current datasets and the multiple load current datasets includes:

[0068] Acquire multiple voltage sampling data of the busbar;

[0069] Based on the multiple voltage sampling data, the fundamental frequency and fundamental phase of the bus voltage are determined;

[0070] Based on the fundamental frequency, the fundamental phase, and the first formula, each of the plurality of grid-connected current datasets and the plurality of load current datasets is extracted to obtain a plurality of grid-connected feature datasets and a plurality of load feature datasets, wherein the first formula is:

[0071]

[0072] In the formula, Feature(n) is the nth feature data in the feature dataset, I(n) is the nth data in the current dataset, I(max) is the maximum value of the current data in the current dataset, cos() is the cosine function, ω0 is the fundamental frequency, N is the number of samples of current data within the fundamental period, and α is the fundamental phase.

[0073] For each target load feeder, multiple target distributed power sources are determined based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets.

[0074] In some implementations, determining multiple target distributed power sources for each target load feeder based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets includes:

[0075] Based on the second formula, the load characteristic dataset of the corresponding target load feeder, and the multiple grid-connected characteristic datasets, the correlation coefficients between multiple distributed power sources and the target load feeder are determined, wherein the second formula is:

[0076]

[0077] In the formula, P ij The correlation coefficient between the i-th distributed power source and the j-th target load feeder. i (n) represents the nth data point in the i-th load feature dataset. j (n) represents the nth data point of the jth grid-connected characteristic dataset, and N is the total number of data points in the characteristic dataset;

[0078] Multiple distributed power sources whose absolute values ​​of correlation coefficients are greater than a threshold are selected as the multiple target distributed power sources.

[0079] In some implementations, determining the fundamental frequency and fundamental phase of the bus voltage based on the plurality of voltage sampling data includes:

[0080] The multiple voltage sampling data are extracted sequentially and accumulated until the sum is less than the threshold.

[0081] Obtain the sampling duration corresponding to the extracted multiple sampled data, and use it as the period of the fundamental frequency;

[0082] The frequency of the fundamental wave is determined based on its period.

[0083] Substituting multiple undetermined phase angles and the extracted sampled data into the third formula, multiple phase angle coefficients are obtained, wherein the third formula is:

[0084]

[0085] In the formula, w k Let U(m) be the k-th phase angle coefficient, U(m) be the m-th data point among the multiple sampled data points, M be the total number of sampled data points, ω0 be the fundamental frequency, cos(ω) be the cosine function, and α be the sine function. k This is the k-th undetermined phase angle;

[0086] The undetermined phase angle corresponding to the phase angle coefficient with the largest value is selected as the fundamental phase.

[0087] For example, such as Figure 2 As shown, in some application scenarios, this illustrates a source-load-storage grid structure, including:

[0088] Busbar 202, pipe end 203, multiple distributed power sources 205, feeder 204, multiple loads 208, feeder 207, and multiple edge ends 206;

[0089] The distributed power source 205 feeder 204 line includes: a power feeder 204 and a distributed power source 205, wherein the distributed power source 205 is connected to the bus 202 through the power feeder 204; the distributed power source 205 includes: a power generation device and an energy storage device, wherein the power generation device generates electricity according to the output indication and / or stores electrical energy in the energy storage device; the first end of the load 208 feeder 207 is electrically connected to the bus 202.

[0090] The plurality of edge terminals 206 are communicatively connected to the pipe terminal 203, and the plurality of edge terminals 206 are used to collect the voltage and current of the plurality of distributed power supply 205 feed lines 204 and the plurality of load 208 feed lines 207;

[0091] The pipe end 203 outputs an indication to adjust the output of the distributed power source 205 based on the access voltage of the bus 202, the voltage and current of the multiple distributed power source 205 feeder lines 204 and the multiple load lines 208, and balances the voltage of the multiple load lines 208 through an iterative process.

[0092] In this diagram, the first end of bus 202 is connected to the output terminal of transformer 201, while the second end of bus 202 is connected to the distributed power source 205 feeder 204 and the load 208 feeder 207. The distributed power source 205 feeder 204 includes a power feeder 204 whose first end is connected to bus 202 and a distributed power source 205 connected to the second end of the power feeder 204.

[0093] The load 208 feeder 207 line includes a load 208 feeder 207 with its first end connected to the bus 202, and a load 208 connected to the second end of the load 208 feeder 207.

[0094] In this system, the distributed power source 205 is equipped with power generation equipment and energy storage equipment. The power generation equipment includes devices such as solar panels and wind turbines, while the energy storage equipment is often in the form of batteries. When the output of the power generation equipment exceeds the total amount of electricity consumed in the distribution network, a portion of the power output of the power generation equipment is stored in the energy storage equipment. Conversely, when the total amount of electricity consumed in the distribution network exceeds the output of the power generation equipment, a portion of the energy stored in the energy storage equipment will be released as needed.

[0095] Based on this, the system can control the output of the distributed power source 205.

[0096] The system also includes a pipe end 203 and an edge end 206. The edge end 206 corresponds to multiple feeders and collects the voltage and current of multiple feeders. In addition to acquiring the voltage of the bus 202 connected to the transformer 201, the pipe end 203 also manages the output of multiple distributed power sources 205.

[0097] The voltage of the load 208 feeder 207 is obtained at the end 206 of the load 208 feeder 207. If the voltage of the load 208 feeder 207 exceeds the voltage range of the bus 202 and the preset voltage range, the terminal 203 will output an indication for the distributed power source 205 to adjust the output based on the current of the load 208 feeder 207 and the power supply feeder 204. After the adjustment is completed, the above voltage acquisition process is repeated. This process is repeated until the voltage in the entire power grid meets the expected requirements.

[0098] Regarding the voltage in the load, in addition to complying with relevant standards and specifications, the voltage of the bus must also be considered. For example, in some scenarios, the voltage of the load feeder cannot be higher than the voltage of the bus power transformer.

[0099] Based on load voltage analysis, in some application scenarios, multiple feeders whose load feeder connection voltage exceeds the above requirements are first identified, and these feeders are then positioned as target feeders.

[0100] If the target feeder voltage is higher than the preset range, it is clearly affected by distributed generation (DG). In this case, efforts should be made to reduce the output of the DG and instead store the generated electrical energy. Due to the complexity of the distribution network topology, identifying the source affecting the load feeder voltage from multiple DG sources through topology analysis is relatively difficult. This invention determines this source through current characteristics. Specifically, it matches the load's current characteristics with the current characteristics of the DG's output. A high degree of matching clearly indicates that the source is a DG affecting the load feeder.

[0101] One approach to current characteristics involves describing the fundamental frequency, fundamental phase, and a first formula, which is used to extract current characteristics from each of the multiple grid-connected current datasets and the multiple load current datasets. The first formula is:

[0102]

[0103] In the formula, Feature(n) is the nth feature data in the feature dataset, I(n) is the nth data in the current dataset, I(max) is the maximum value of the current data in the current dataset, cos() is the cosine function, ω0 is the fundamental frequency, N is the number of samples of current data within the fundamental period, and α is the fundamental phase.

[0104] Once the features are obtained, multiple distributed power sources can be matched with each target feeder. In this embodiment of the invention, the matching coefficients are obtained using the second formula:

[0105]

[0106] In the formula, P ij The correlation coefficient between the i-th distributed power source and the j-th target load feeder. i (n) represents the nth data point in the i-th load feature dataset. j (n) represents the nth data point of the j-th grid-connected feature dataset, and N represents the total number of data points in the feature dataset.

[0107] For the matching coefficient, the higher the absolute value, the stronger the correlation. A negative value indicates a negative correlation, and vice versa. Distributed power sources with absolute values ​​higher than a threshold are retained as the target power sources for regulation.

[0108] The above process mentions the determination of the fundamental frequency and phase. In this embodiment of the invention, a determination method is provided. For example, in determining the fundamental frequency, multiple voltage sampling data on the bus are taken out sequentially and accumulated until the sum is less than a threshold. The sampling duration corresponding to the multiple sampling data is taken as the period of the fundamental frequency. Then, the reciprocal of the fundamental frequency period is the fundamental frequency. Note that the fundamental frequency used here can be understood as the bus voltage waveform in some scenarios. In other scenarios, due to the distortion of the bus waveform, the fundamental frequency refers to the trigonometric function waveform that accounts for the largest proportion of the bus voltage waveform.

[0109] For the phase of the fundamental wave, one approach is to substitute multiple possible phase angles into the third formula to obtain the phase angle coefficients. The phase angle with the largest phase angle coefficient is the phase of the fundamental wave. The third formula is:

[0110]

[0111] In the formula, w k Let U(m) be the k-th phase angle coefficient, U(m) be the m-th data point among the multiple sampled data points, M be the total number of sampled data points, ω0 be the fundamental frequency, cos(ω) be the cosine function, and α be the sine function. k This is the k-th undetermined phase angle.

[0112] In some implementations, adjusting the output of the plurality of target distributed power sources based on their influence coefficients on the plurality of target load feeders includes:

[0113] Based on the influence coefficients of the multiple target distributed power sources on the multiple target load feeders and the fourth formula, the grid connection voltage of the multiple target distributed power sources is adjusted, wherein the fourth formula is:

[0114]

[0115] In the formula, U′ i Let γ be the grid-connected voltage after adjustment for the i-th target distributed power source, γ be the adjustment coefficient, J be the total number of target load feeders affected by the i-th target distributed power source, and P be the grid-connected voltage after adjustment for the i-th target distributed power source. ij U is the correlation coefficient between the i-th distributed power source and the j-th target load feeder. i The grid-connected voltage before adjustment for the i-th target distributed power source.

[0116] For example, regarding the output adjustment of the target distributed power source, which mainly targets its grid connection voltage, the embodiment of the present invention uses the fourth formula to determine the target adjustment voltage:

[0117]

[0118] In the formula, U′ i Let γ be the grid-connected voltage after adjustment for the i-th target distributed power source, γ be the adjustment coefficient, J be the total number of target load feeders affected by the i-th target distributed power source, and P be the grid-connected voltage after adjustment for the i-th target distributed power source. ij U is the correlation coefficient between the i-th distributed power source and the j-th target load feeder. i The grid-connected voltage before adjustment for the i-th target distributed power source.

[0119] This invention discloses an implementation method for overvoltage mitigation in distributed power grids. First, it acquires the bus voltage, where multiple distributed power sources are connected to the bus for grid-connected generation, and loads are connected to the bus via load feeders. The bus voltage is the voltage at the main power source terminal of the bus. Then, based on the bus voltage and a predetermined voltage range, the voltage of the multiple load lines is balanced by iteratively identifying multiple target load feeders and adjusting the output of multiple target distributed power sources. The target load feeders are those whose voltage exceeds the predetermined range, and the target distributed power sources are those whose output affects the voltage of the target load feeders. This embodiment of the invention uses an iterative approach of finding target load feeders exceeding the predetermined voltage range and adjusting the distributed power sources affecting them to adjust the voltage of multiple load feeders in the source-load-storage power grid, thereby stabilizing the voltage in the distributed power grid. Because this method determines the target distributed power sources based on the influence of distributed power source output on load feeder voltage, it is unaffected by the grid structure and has a lower computational load and faster response compared to methods based on topology analysis.

[0120] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. 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 embodiments of the present invention.

[0121] The following are embodiments of the apparatus of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0122] Figure 3 This is a functional block diagram of the distributed power grid overvoltage control device provided in the embodiments of the present invention, with reference to... Figure 3 The distributed power grid overvoltage control device 3 includes: a bus voltage acquisition module 301 and an iterative balancing module 302, wherein:

[0123] The bus voltage acquisition module 301 is used to acquire the bus voltage, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through the load feeder, and the bus voltage is the voltage at the main power supply terminal of the bus.

[0124] The iterative balancing module 302 is used to balance the voltage of the multiple load lines by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources based on the bus voltage and a predetermined voltage range. The target load feeders are load feeders whose voltage exceeds the predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders.

[0125] Figure 4This is a functional block diagram of the terminal provided in an embodiment of the present invention. For example... Figure 4 As shown, the terminal 4 in this embodiment includes a processor 400 and a memory 401, wherein the memory 401 stores a computer program 402 that can run on the processor 400. When the processor 400 executes the computer program 402, it implements the steps of the various distributed power grid overvoltage control methods and embodiments described above, for example... Figure 1 Steps 101 to 102 are shown.

[0126] For example, the computer program 402 may be divided into one or more modules / units, which are stored in the memory 401 and executed by the processor 400 to complete the present invention.

[0127] The terminal 4 can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. The terminal 4 may include, but is not limited to, a processor 400 and a memory 401. Those skilled in the art will understand that... Figure 4 This is merely an example of terminal 4 and does not constitute a limitation on terminal 4. It may include more or fewer components than shown, or combine certain components, or different components. For example, terminal 4 may also include input / output devices, network access devices, buses, etc.

[0128] The processor 400 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0129] The memory 401 can be an internal storage unit of the terminal 4, such as a hard disk or memory of the terminal 4. The memory 401 can also be an external storage device of the terminal 4, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the terminal 4. Furthermore, the memory 401 can include both internal storage units and external storage devices of the terminal 4. The memory 401 is used to store the computer program 402 and other programs and data required by the terminal 4. The memory 401 can also be used to temporarily store data that has been output or will be output.

[0130] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the aforementioned method embodiments, and will not be repeated here.

[0131] In the above embodiments, the descriptions of each embodiment have their own emphasis. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0132] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0133] In the embodiments provided by this invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0134] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0135] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0136] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above-described embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various methods and apparatus embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0137] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for managing overvoltage in distributed power grids, characterized in that, include: Obtain the bus voltage, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through the load feeder, and the bus voltage is the voltage at the main power supply terminal of the bus; Based on the bus voltage and a predetermined voltage range, the voltage of multiple load lines is balanced by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources, including: Target load feeder determination steps: Based on the bus voltage and the predetermined voltage range, determine multiple target load feeders; Based on multiple grid-connected current datasets and multiple load current datasets, multiple target distributed power sources are determined. The multiple grid-connected current datasets correspond to multiple distributed power sources, and the multiple load current datasets are obtained based on multiple target load feeders. The target load feeders are load feeders whose voltage exceeds a predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders. The output of the multiple target distributed power sources is adjusted according to the influence coefficients of the multiple target load feeders. Based on the bus voltage and the predetermined voltage range, check the voltage of the plurality of load feeders. If the voltage of the plurality of load feeders exceeds the predetermined range, proceed to the target load feeder determination step.

2. The distributed power grid overvoltage control method according to claim 1, characterized in that, The step of determining multiple target distributed power sources based on the multiple grid-connected current datasets and the multiple load current datasets includes: Acquire multiple voltage sampling data of the busbar; Based on the multiple voltage sampling data, the fundamental frequency and fundamental phase of the bus voltage are determined; Based on the fundamental frequency, the fundamental phase, and the first formula, each of the plurality of grid-connected current datasets and the plurality of load current datasets is extracted to obtain a plurality of grid-connected feature datasets and a plurality of load feature datasets, wherein the first formula is: In the formula, For the feature dataset, the first Each feature data, For the current dataset, the first One data point, The maximum value of the current data in the current dataset. It is a cosine function. The fundamental frequency, This represents the number of samples of current data within the fundamental frequency period. The fundamental phase; For each target load feeder, multiple target distributed power sources are determined based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets.

3. The distributed power grid overvoltage control method according to claim 2, characterized in that, For each target load feeder, multiple target distributed power sources are determined based on the correlation between the load characteristic dataset of the corresponding target load feeder and the multiple grid-connected characteristic datasets, including: Based on the second formula, the load characteristic dataset of the corresponding target load feeder, and the multiple grid-connected characteristic datasets, the correlation coefficients between multiple distributed power sources and the target load feeder are determined, wherein the second formula is: In the formula, For the first The distributed power source and the first The correlation coefficient of each target load feeder For the first The first load feature dataset One data point, For the first The first of the grid-connected characteristic datasets One data point, This represents the total number of data points in the feature dataset. Multiple distributed power sources whose absolute values ​​of correlation coefficients are greater than a threshold are selected as the multiple target distributed power sources.

4. The distributed power grid overvoltage control method according to any one of claims 2-3, characterized in that, The step of determining the fundamental frequency and fundamental phase of the bus voltage based on the multiple voltage sampling data includes: The multiple voltage sampling data are extracted sequentially and accumulated until the sum is less than the threshold. Obtain the sampling duration corresponding to the extracted multiple sampled data, and use it as the period of the fundamental frequency; The frequency of the fundamental wave is determined based on its period. Substituting multiple undetermined phase angles and the extracted sampled data into the third formula, multiple phase angle coefficients are obtained, wherein the third formula is: In the formula, For the first Phase angle coefficients, For the first of the multiple sampled data points One data point, The total number of multiple sampled data points retrieved. The fundamental frequency, It is a cosine function. For the first One undetermined phase angle; The undetermined phase angle corresponding to the phase angle coefficient with the largest value is selected as the fundamental phase.

5. The distributed power grid overvoltage control method according to any one of claims 1-3, characterized in that, The step of adjusting the output of the multiple target distributed power sources based on their influence coefficients on the multiple target load feeders includes: Based on the influence coefficients of the multiple target distributed power sources on the multiple target load feeders and the fourth formula, the grid connection voltage of the multiple target distributed power sources is adjusted, wherein the fourth formula is: In the formula, For the first The grid-connected voltage after adjustment for each target distributed power source To adjust the coefficient, For the first The total number of target load feeders affected by the target distributed power source. For the first The distributed power source and the first The correlation coefficient of each target load feeder For the first The grid connection voltage of the target distributed power source before adjustment.

6. A distributed power grid overvoltage control device, characterized in that, For implementing the distributed power grid overvoltage mitigation method as described in any one of claims 1-5, the distributed power grid overvoltage mitigation device comprises: A bus voltage acquisition module is used to acquire the bus voltage, wherein multiple distributed power sources achieve grid-connected power generation by connecting to the bus, and the load is connected to the bus through a load feeder, and the bus voltage is the voltage at the main power supply terminal of the bus; as well as, The iterative balancing module is used to balance the voltage of the multiple load lines by iteratively determining multiple target load feeders and adjusting the output of multiple target distributed power sources based on the bus voltage and a predetermined voltage range. The target load feeders are load feeders whose voltage exceeds the predetermined range, and the target distributed power sources are distributed power sources whose output affects the voltage of the target load feeders.

7. A terminal comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 5 above.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 5 above.

Images