A diagnostic method, device and equipment for a hydropower station to be incorporated into the power grid system

Abstract

The present invention discloses a diagnostic method, device and equipment for a hydropower station to be incorporated into a power grid system. The method includes obtaining grid connection demand information of the hydropower station; obtaining first voltage information of the hydropower station and second voltage information of the power grid to be connected based on the grid connection demand information; determining whether the deviation between the first voltage information and the second voltage information meets a preset deviation range; if so, determining whether the power grid to be connected meets the grid connection requirements; if so, incorporating the hydropower station into the power grid to be connected. The present invention can diagnose whether a hydropower station needs to be incorporated into the power grid system, avoiding the instability of the power grid system caused by incorporating a hydropower station that does not meet the grid connection requirements into the power grid system, thereby affecting the normal working state of the power grid system, and improving the stability and safety of the operation of the power grid system.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of power systems, and in particular, to a diagnostic method, device, and equipment for a hydropower station to be connected to a power grid system. Background Art

[0002] In recent years, hydropower generation, as a clean, pollution-free, and widely distributed power generation method, has been widely promoted and applied. Hydropower generation mainly relies on hydropower stations to convert water energy into electrical energy, transmit the electrical energy to thousands of households, and ensure the electricity demand of users.

[0003] In the prior art, for the diagnostic method of whether a hydropower station needs to be connected to a power grid system, usually, the voltage information, frequency information, and phase information of the hydropower station and the voltage information, frequency information, and phase information of the power grid system are compared to determine whether to connect the hydropower station to the power grid system. However, there is a lack of judgment on the stability of the power grid system and whether it meets the requirements for connecting the hydropower station, which may lead to incorrect judgments and affect the stability and safety of the power grid system. Summary of the Invention

[0004] The present invention provides a diagnostic method, device, and equipment for a hydropower station to be connected to a power grid system, so as to realize the judgment of connecting a hydropower station to a power grid system, avoid the problem that the power grid system does not meet the grid connection requirements after the hydropower station is connected to the power grid system, which affects the normal working state of the power grid system, and improve the stability and safety of the operation of the power grid system.

[0005] In a first aspect, the present invention provides a diagnostic method for a hydropower station to be connected to a power grid system, including:

[0006] Obtain the grid connection requirement information of the hydropower station;

[0007] Based on the grid connection requirement information, obtain the first voltage information of the hydropower station and the second voltage information of the power grid to be connected;

[0008] Judge whether the deviation between the first voltage information and the second voltage information meets a preset deviation range;

[0009] If so, judge whether the power grid to be connected meets the grid connection requirements;

[0010] If so, connect the hydropower station to the power grid to be connected.

[0011] Optionally, within a preset time, obtain the second voltage frequency information in the second voltage information to obtain multiple frequency values;

[0012] Judge the type information of the power grid to be connected according to the proportion of multiple frequency values within a reference frequency range;

[0013] Judge whether the grid to be connected meets the grid connection requirements according to the type information and multiple frequency values.

[0014] Optionally, when the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, judge that the grid to be connected is a large grid;

[0015] When the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, judge that the grid to be connected is a microgrid; the frequency values of the microgrid are different from those of the large grid.

[0016] Optionally, the reference frequency range includes a first frequency endpoint value and a second frequency endpoint value, and the first frequency endpoint value is less than the second frequency endpoint value;

[0017] Judging whether the grid to be connected meets the grid connection requirements according to the type information and multiple frequency values includes:

[0018] When the grid to be connected is a large grid, judge that the grid to be connected meets the grid connection requirements;

[0019] When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all less than the first frequency endpoint value, judge that the grid to be connected meets the grid connection requirements;

[0020] When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all greater than the second frequency endpoint value, judge that the grid to be connected does not meet the grid connection requirements;

[0021] When the grid to be connected is a microgrid and among multiple frequency values not within the reference frequency range, some are greater than the second frequency endpoint value and some are less than the first frequency endpoint value, judge that the grid to be connected does not meet the grid connection requirements.

[0022] Optionally, when the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, judging that the grid to be connected is a large grid includes:

[0023] When the proportion of multiple frequency values within the reference frequency range is greater than or equal to 50%, judge that the grid to be connected is a large grid;

[0024] When the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, judging that the grid to be connected is a microgrid includes:

[0025] When the proportion of multiple frequency values within the reference frequency range is less than 50%, judge that the grid to be connected is a microgrid.

[0026] Optionally, perform a Fourier transform on the second voltage information to obtain a Fourier transform result;

[0027] Obtain second voltage frequency information in the second voltage information according to the Fourier transform result.

[0028] Optionally, after determining whether the power grid to be connected meets the grid connection requirements, it further includes: if not, control the hydropower station to operate in an islanded grid.

[0029] Optionally, the first voltage information includes first voltage amplitude information, first voltage frequency information, and first voltage phase information;

[0030] The second voltage information includes second voltage amplitude information, second voltage frequency information, and second voltage phase information;

[0031] Determining whether the deviation between the first voltage information and the second voltage information meets a preset deviation range includes:

[0032] Determine whether the deviation between the first voltage amplitude information and the second voltage amplitude information meets a preset amplitude deviation range;

[0033] Determine whether the deviation between the first voltage frequency information and the second voltage frequency information meets a preset frequency deviation range;

[0034] Determine whether the deviation between the first voltage phase information and the second voltage phase information meets a preset phase deviation range.

[0035] In a second aspect, the present invention further provides a diagnostic device for a hydropower station to be connected to a power grid system, including:

[0036] A grid connection requirement information acquisition module for acquiring grid connection requirement information of the hydropower station;

[0037] A voltage information acquisition module for acquiring first voltage information of the hydropower station and second voltage information of the power grid to be connected based on the grid connection requirement information;

[0038] A first judgment module for judging whether the deviation between the first voltage information and the second voltage information meets a preset deviation range;

[0039] A second judgment module for judging whether the power grid to be connected meets the grid connection requirements when the deviation between the first voltage information and the second voltage information meets a preset deviation range;

[0040] A grid connection module for connecting the hydropower station to the power grid to be connected when the power grid to be connected meets the grid connection requirements.

[0041] Thirdly, the present invention further provides a diagnostic device, which includes:

[0042] One or more processors;

[0043] A storage device for storing one or more programs;

[0044] When the one or more programs are executed by the one or more processors, the one or more processors implement the diagnostic method for a hydropower station integrating into the power grid system provided by any implementation of the present invention.

[0045] After obtaining the grid connection demand information of the hydropower station, the present invention obtains the voltage information of the hydropower station and the power grid to be connected according to the grid connection demand information, where the voltage information of the hydropower station is the first voltage information and the voltage information of the power grid to be connected is the second voltage information. The first voltage information and the second voltage information are compared to judge the magnitude relationship between the deviation of the voltage information and the preset deviation range. When the deviation between the first voltage information and the second voltage information meets the preset deviation range, then judge the situation of the power grid to be connected meeting the grid connection requirements. When the power grid to be connected is in a state of meeting the grid connection requirements, then integrate the hydropower station into the power grid to be connected. The technical solution provided by the present invention realizes the diagnosis of whether the hydropower station needs to be integrated into the power grid system, avoids the problem that the power grid system does not meet the grid connection requirements after the hydropower station is integrated into the power grid system, which affects the normal working state of the power grid system, and improves the grid connection requirement compliance and safety of the power grid system operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 It is a schematic flowchart of a diagnostic method for a hydropower station integrating into the power grid system provided by Embodiment 1 of the present invention;

[0048] Figure 2 It is a schematic flowchart of a diagnostic method for a hydropower station integrating into the power grid system provided by Embodiment 2 of the present invention;

[0049] Figure 3 It is a schematic flowchart of a diagnostic method for a hydropower station integrating into the power grid system provided by Embodiment 3 of the present invention;

[0050] Figure 4 It is a schematic structural diagram of a diagnostic device for a hydropower station integrating into the power grid system provided by Embodiment 4 of the present invention;

[0051] Figure 5 FIG. 1 is a schematic structural diagram of a diagnostic device according to Embodiment 5 of the present invention. Detailed implementation manners

[0052] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0053] It should be noted that the terms "first", "second", etc. in the specification and claims 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 such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0054] Embodiment 1

[0055] Figure 1 FIG. 2 is a schematic flow chart of a method for diagnosing a hydropower station integrating into a power grid system according to Embodiment 1 of the present invention. This method can be executed by a diagnostic device for a hydropower station integrating into a power grid system, and this device can be composed of hardware and / or software. The method for diagnosing a hydropower station integrating into a power grid system provided by the embodiments of the present invention includes the following steps:

[0056] S110. Obtain the grid connection demand information of the hydropower station.

[0057] Among them, a hydropower station can convert water energy into electrical energy. The electrical energy is transmitted to the user side through the power grid and transformers to meet the electricity demand of users. There are two main transmission paths for the electrical energy output by the hydropower station. One is that the electrical energy is supplied to users through relevant equipment such as the power grid and transformers. The other is to incorporate the electrical energy into the power grid system of a large area or a small area. The power grid system adjusts the power supply of the entire power grid system according to the electricity demand. When the hydropower station has a grid connection demand, by obtaining the grid connection demand information of the hydropower station, the grid connection situation between the hydropower station and the power grid system is further determined. Knowing the grid connection demand information of the hydropower station is one of the conditions for realizing the grid connection between the hydropower station and the grid system. Subsequently, the realization of the grid connection between the hydropower station and the power grid system needs to be determined according to other factors. The grid connection demand information specifically refers to the information that the hydropower station intends to connect to the power grid system.

[0058] S120. Obtain the first voltage information of the hydropower station and the second voltage information of the grid to be connected based on the grid connection demand information.

[0059] Among them, when it is known from the grid connection demand information that the hydropower station intends to connect to the grid, it is necessary to obtain the first voltage information of the hydropower station and the second voltage information of the grid to be connected. Specifically, the first voltage information includes the first voltage amplitude information, the first voltage frequency information, and the first voltage phase information. Similarly, the second voltage information includes the second voltage amplitude information, the second voltage frequency information, and the second voltage phase information. The first voltage amplitude information and the second voltage amplitude information can be obtained by using an intelligent electricity meter to measure the output voltage of the hydropower station and the output voltage of the grid to be connected respectively. Exemplarily, the amplitude information of the voltage can be 400V, 6.3kV, 12kV, and no specific limitation is made here. The voltage frequency information is determined according to the current value and voltage amplitude read by the intelligent electricity meter. The current value and voltage amplitude show a sinusoidal change trend. By using software algorithms such as the Fourier transform algorithm, the voltage frequency information and voltage phase information can be calculated. Specifically, the first voltage frequency information and the first voltage phase information of the hydropower station are obtained by using an intelligent electricity meter to measure the first voltage amplitude and the first current value output by the hydropower station. Based on the sinusoidal change of the first voltage amplitude and the first current value, the first voltage frequency information and the first voltage phase information are calculated by using the Fourier transform algorithm. In a similar manner, the second voltage frequency information and the second voltage phase information of the grid to be connected are obtained by using an intelligent electricity meter to measure the second voltage amplitude and the second current value at the grid to be connected. According to the sinusoidal change of the second voltage amplitude and the second current value, the second voltage frequency information and the second voltage phase information are calculated by using the Fourier transform method.

[0060] S130. Judge whether the deviation between the first voltage information and the second voltage information meets the preset deviation range. If so, execute S140.

[0061] Among them, the first voltage information and the second voltage information respectively correspond to the voltage information of the hydropower station and the voltage information of the grid to be connected. During the measurement of the first voltage information and the second voltage information, there will be a certain degree of fluctuation, resulting in a deviation between the first voltage information and the second voltage information. By comparing the deviation between the first voltage information and the second voltage information with the preset deviation range, it is determined whether the deviation between the first voltage information and the second voltage information meets the preset deviation range.

[0062] Specifically, the judgment of the preset deviation range includes a preset amplitude deviation range, a preset frequency deviation range, and a preset phase deviation range. That is, during the judgment process, it is necessary to judge whether the deviation between the first voltage amplitude information and the second voltage amplitude information meets the preset amplitude deviation range, judge whether the deviation between the first voltage frequency information and the second voltage frequency information meets the preset frequency deviation range, and judge whether the deviation between the first voltage phase information and the second voltage phase information meets the preset phase deviation range.

[0063] Exemplarily, the preset amplitude deviation range can be set within 5%. That is, when the deviation between the first voltage amplitude information and the second voltage amplitude information is within the preset amplitude deviation range of 5%, the voltage amplitude information meets the amplitude deviation requirement. When the first voltage amplitude is 10 kV and the second voltage amplitude is 10.3 kV, the amplitude deviation range is 3%, which is less than the preset amplitude deviation range. The judgment method of the deviation between the first voltage frequency information and the second voltage frequency information and the preset frequency deviation range is similar to that of the voltage amplitude. When the first voltage frequency information is 50.00 Hz and the second voltage frequency information is 50.2 Hz, the frequency deviation is 0.2 Hz. When the preset frequency deviation range is 0 - 0.3 Hz, the deviation between the first voltage frequency information and the second voltage frequency information meets the requirement. When the deviation between the first voltage phase information and the second voltage phase information reaches the preset phase deviation range, it is determined that the deviation between the first voltage phase information and the second voltage phase information meets the requirement. Here, it is only exemplary, and the specific preset amplitude deviation range, preset frequency deviation range, and preset phase deviation range are not limited and can be further determined according to the actual situation.

[0064] S140. Judge whether the grid to be connected meets the grid connection requirements. If so, execute S150.

[0065] When it is judged that the deviation between the first voltage information and the second voltage information meets the preset deviation range, that is, the amplitude deviation range, the frequency deviation range, and the phase deviation range all meet the conditions. Further judge whether the grid to be connected meets the grid connection requirements. The determination of whether the grid to be connected meets the grid connection requirements is mainly through monitoring the frequency of the grid to be connected within the set time range, reading and recording the frequency fluctuation of the grid to be connected within the set time range.

[0066] S150. Incorporate the hydropower station into the grid to be connected.

[0067] Among them, only when the deviation between the first voltage information of the hydropower station and the second voltage information of the grid to be connected meets the preset deviation range and the grid to be connected is a grid that meets the grid connection requirements, can the hydropower station be incorporated into the grid to be connected. When any of the voltage amplitude information, voltage frequency information, and voltage phase information of the deviation between the first voltage information of the hydropower station and the second voltage information of the grid to be connected does not meet the preset deviation range or the grid to be connected does not meet the grid connection requirements, the hydropower station will not be incorporated into the grid to be connected.

[0068] Optionally, when the grid to be connected does not meet the grid connection requirements, control the hydropower station to operate in an isolated grid. It can be understood that the grid to be connected is a grid that does not meet the grid connection requirements and does not have the conditions to incorporate the hydropower station into the grid. Then the hydropower station operates in an isolated grid instead of being connected to the grid. An isolated grid means that the hydropower station is not connected to the main grid of the power system. The electric energy generated by the hydropower station provides power supply for users, and there is no need to transmit the electric energy to the main grid for power distribution by the main grid again.

[0069] After obtaining the grid connection requirement information of the hydropower station in the embodiment of the present invention, the voltage information of the hydropower station and the grid to be connected is obtained according to the grid connection requirement information. Among them, the voltage information of the hydropower station is the first voltage information, and the voltage information of the grid to be connected is the second voltage information. Compare the first voltage information and the second voltage information, and judge the size relationship between the deviation of the voltage information and the preset deviation range. When the deviation between the first voltage information and the second voltage information meets the preset deviation range, then judge the situation of the grid to be connected meeting the grid connection requirements. When the grid to be connected is in a state that meets the grid connection requirements, the hydropower station is incorporated into the grid to be connected. The technical solution provided by the embodiment of the present invention realizes the diagnosis of whether the hydropower station needs to be incorporated into the power grid system, avoids the situation that the power grid system does not meet the grid connection requirements after the hydropower station is incorporated into the power grid system, which affects the normal working state of the power grid system, and improves the stability and safety of the operation of the power grid system.

[0070] Embodiment 2

[0071] Figure 2 It is a schematic flowchart of a method for diagnosing the incorporation of a hydropower station into a power grid system according to Embodiment 2 of the present invention. On the basis of the above embodiment, a solution for judging whether the grid to be connected meets the grid connection requirements is specifically provided. The technical solution of this embodiment includes:

[0072] S210. Obtain the grid connection requirement information of the hydropower station.

[0073] S220. Obtain the first voltage information of the hydropower station and the second voltage information of the grid to be connected based on the grid connection requirement information.

[0074] S230. Determine whether the deviation between the first voltage information and the second voltage information meets the preset deviation range. If so, execute S240.

[0075] S240. Obtain the second voltage frequency information in the second voltage information within a preset time to obtain multiple frequency values.

[0076] Among them, the second voltage information is the voltage information of the grid to be paralleled. The second voltage information includes the second voltage frequency information. The voltage frequency values corresponding to different times are different. Within the preset time range, monitor and record multiple frequency values within the preset time range. The preset time range can be set in advance and is not specifically limited here.

[0077] Optionally, perform a Fourier transform on the second voltage information to obtain a Fourier transform result;

[0078] According to the Fourier transform result, obtain the second voltage frequency information in the second voltage information.

[0079] Among them, the second voltage frequency information is obtained by performing a Fourier transform on the second voltage information of the smart meter. After the Fourier transform, the second voltage frequency information is obtained. The Fourier transform can represent a certain function that meets certain conditions as a linear combination of trigonometric functions or integrals of functions. The same transformation method is used for the second voltage frequency information, mainly through a series of transformations and conversions of the second voltage information to determine the second voltage frequency information.

[0080] S250. Determine the type information of the grid to be paralleled according to the proportion of multiple frequency values within the reference frequency range.

[0081] Among them, the reference frequency range can be set in advance. Exemplarily, the reference frequency range is 49.8 - 50.2 Hz. Record multiple frequency values within the preset time and judge the relationship between the multiple frequency values and the reference frequency range. When the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, the grid to be paralleled is a large grid; when the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, the grid to be paralleled is a microgrid. A large grid refers to a grid system whose frequency can meet the grid connection requirements within the reference frequency range, and can also be understood as a regional grid in the power system. The regional grid may include the grid of a hydropower station but is not limited to the grid of a hydropower station. A microgrid refers to a grid composed of multiple hydropower stations. The microgrid can meet the power supply needs of users in a small area without being connected to the main grid of the power system. When the main grid of the power system needs electricity, it can also connect the microgrid that meets the grid connection requirements to the main grid. The main grid of the power system can also be understood as a large grid.

[0082] Specifically, there may be fluctuations in the multiple frequency values obtained within the preset time. After the fluctuations, the frequency values may deviate from the reference frequency range or may be within the reference frequency range. Determine the type of the power grid to be connected based on the ratio of the multiple frequency values within the reference frequency range.

[0083] Optionally, when the ratio of the multiple frequency values within the reference frequency range is greater than or equal to 50%, determine that the power grid to be connected is a large power grid; when the ratio of the multiple frequency values within the reference frequency range is less than 50%, determine that the power grid to be connected is a microgrid, and the frequency value of the microgrid is different from that of the large power grid.

[0084] Furthermore, generally, the frequency value in the large power grid is relatively stable with small fluctuations. For a power grid in the power grid system with a relatively small frequency fluctuation range, that is, a power grid where the ratio of the multiple frequency values within the reference frequency range is greater than or equal to 50% is defined as a large power grid. While the frequency value in the microgrid generally has large fluctuations, and a power grid with a ratio of the multiple frequency values less than 50% is defined as a microgrid, that is, the frequency fluctuates greatly within the reference frequency range and is less stable than the large power grid.

[0085] S260. Determine whether the power grid to be connected meets the grid connection requirements based on the type information and the multiple frequency values. If so, execute S270.

[0086] Among them, the type information can determine whether the power grid to be connected is a large power grid or a microgrid, and the multiple frequency values and the type information can further determine the situation where the power grid to be connected meets the grid connection requirements.

[0087] S270. Incorporate the hydropower station into the power grid to be connected.

[0088] Exemplarily, set the time range to 10 min. Monitor the frequency of the power grid to be connected within 10 min. Usually, the frequency of the power grid to be connected is basically within the range of 50 Hz, that is, the average period is 0.02 s. Monitoring the frequency for 10 min is equivalent to experiencing 30,000 cycles. For each cycle experienced, read and record the change in frequency. When the frequency of the power grid to be connected basically remains at a value around 50 Hz within 10 min, it can be determined that the power grid to be connected meets the grid connection requirements.

[0089] In the embodiments of the present invention, the type information of the power grid to be connected is determined according to the proportion of multiple frequency values within the reference frequency range, where the type information is a microgrid or a large grid. According to the type information and multiple frequency values, it is determined whether the microgrid meets the grid connection requirements or the large grid meets the grid connection requirements, so as to determine whether to incorporate the hydropower station into the power grid to be connected based on whether the power grid to be connected meets the grid connection requirements. The technical solution provided by the embodiments of the present invention realizes the diagnosis of whether the hydropower station needs to be incorporated into the power grid system, avoids the problem of instability of the power grid system caused by the incorporation of the hydropower station into the power grid system, affects the normal working state of the power grid system, and improves the stability and safety of the operation of the power grid system.

[0090] Embodiment III

[0091] Figure 3 It is a schematic flowchart of a method for diagnosing the incorporation of a hydropower station into a power grid system according to Embodiment III of the present invention. On the basis of the above embodiments, a solution for judging whether the power grid to be connected meets the grid connection requirements according to the type information is specifically provided. The technical solution of this embodiment includes:

[0092] S301. Obtain the grid connection requirement information of the hydropower station.

[0093] S302. Based on the grid connection requirement information, obtain the first voltage information of the hydropower station and the second voltage information of the power grid to be connected.

[0094] S303. Judge whether the deviation between the first voltage information and the second voltage information meets the preset deviation range. If so, execute S304.

[0095] S304. Within the preset time, obtain the second voltage frequency information in the second voltage information to obtain multiple frequency values.

[0096] S305. When the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, judge that the power grid to be connected is a large grid;

[0097] S306. When the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, judge that the power grid to be connected is a microgrid;

[0098] Among them, the reference frequency range includes a first frequency point value and a second frequency end value, and the first frequency end value is less than the second frequency end value. An exemplary reference frequency range is 49.8 - 50.2 Hz, the first frequency end value is 49.8 Hz, and the second frequency end value is 50.2 Hz. This is only an exemplary representation, and the specific reference frequency range can be determined according to the actual situation.

[0099] S307. When the power grid to be connected is a large grid, judge that the power grid to be connected meets the grid connection requirements.

[0100] Among them, when the type information is a large power grid and the proportion of multiple frequency values within the reference frequency range meets the proportion requirement, it is determined that the grid to be connected meets the grid connection requirement.

[0101] S308. When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all less than the first frequency endpoint value, it is determined that the grid to be connected meets the grid connection requirement.

[0102] Among them, when the type information is a microgrid, multiple frequency values of the microgrid are not within the reference frequency range, and multiple frequency values are all less than the first frequency endpoint value, it is determined that the grid to be connected meets the grid connection requirement. Exemplarily, the reference frequency range is 49.8 - 50.2 Hz, and multiple frequency values not within 49.8 - 50.2 Hz are all less than 49.8 Hz, then the grid to be connected meets the grid connection requirement and the hydropower station can be connected.

[0103] Further, when multiple frequency values of the microgrid are not within the reference frequency range, and multiple frequency values are all less than the first frequency endpoint value, the power of the grid to be connected cannot meet the power consumption demand of users, and the active power output by the grid to be connected is less than the active power required by the load. By connecting the hydropower station to the grid to be connected, the active power output by the grid to be connected is increased, so that the power of the grid to be connected is basically balanced with the power required by the load, and the frequency is stabilized within the reference frequency range. By comparing the active power output by the grid to be connected with the active power required by the load, it can be further known whether it is necessary to connect the hydropower station for grid connection operation.

[0104] S309. When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all greater than the second frequency endpoint value, it is determined that the grid to be connected does not meet the grid connection requirement.

[0105] Among them, when the type information is a microgrid, multiple frequency values of the microgrid are not within the reference frequency range, and multiple frequency values are all greater than the second frequency endpoint value, it is determined that the grid to be connected does not meet the grid connection requirement. Exemplarily, the reference frequency range is 49.8 - 50.2 Hz, and multiple frequency values not within 49.8 - 50.2 Hz are all greater than 50.2 Hz, then the grid to be connected does not meet the grid connection requirement, and connecting the hydropower station to the power station will affect the grid to be connected.

[0106] Further, when multiple frequency values of the microgrid are not within the reference frequency range, and multiple frequency values are all greater than the first frequency endpoint value, the active power output by the grid to be connected is greater than the active power required by the load, and the grid to be connected does not meet the grid connection requirement, then there is no need to connect the hydropower station to the grid to be connected.

[0107] S310. When the grid to be connected is a microgrid and among multiple frequency values not within the reference frequency range, some are greater than the second frequency endpoint value and some are less than the first frequency endpoint value, it is determined that the grid to be connected does not meet the grid connection requirements.

[0108] Among them, when the type information is a microgrid and among multiple frequency values in the microgrid not within the reference frequency range, some are greater than the second frequency endpoint value and some are less than the first frequency endpoint value, it indicates that the grid to be connected does not meet the grid connection requirements and it is impossible to connect the hydropower station to the grid. Exemplarily, the reference frequency range is 49.8 - 50.2 Hz, where some frequency values are less than 49.8 Hz and some are greater than 50.2 Hz. Here, the frequency of the microgrid does not meet the grid connection requirements and is not suitable for connecting to the hydropower station. That is, the frequency of the microgrid itself is unstable and does not meet the grid connection requirements, so the hydropower station is not connected to the grid.

[0109] S311. If so, connect the hydropower station to the grid to be connected.

[0110] In the embodiment of the present invention, the type information of the grid to be connected is determined, where the type information is a microgrid or a large grid. According to the type information and multiple frequency values, it is determined whether the microgrid meets the grid connection requirements or the large grid meets the grid connection requirements, so as to determine whether to connect the hydropower station to the grid to be connected based on whether the grid to be connected meets the grid connection requirements. The technical solution provided by the embodiment of the present invention realizes the diagnosis of whether the hydropower station needs to be connected to the grid system, avoids the problem that the grid system is unstable after the hydropower station is connected to the grid system, which affects the normal working state of the grid system, and improves the stability and security of the operation of the grid system.

[0111] Embodiment 4

[0112] Figure 4 It is a schematic structural diagram of a diagnosis device for connecting a hydropower station to a grid system according to Embodiment 4 of the present invention. This device can be composed of hardware and / or software. As Figure 4 shown, this device includes: a grid connection requirement information acquisition module 410, a voltage information acquisition module 420, a first judgment module 430, a second judgment module 440, and a grid connection module 450.

[0113] The grid connection requirement information acquisition module 410 is used to acquire the grid connection requirement information of the hydropower station.

[0114] The voltage information acquisition module 420 is used to acquire the first voltage information of the hydropower station and the second voltage information of the grid to be connected based on the grid connection requirement information.

[0115] The first judgment module 430 is used to judge whether the deviation between the first voltage information and the second voltage information meets the preset deviation range.

[0116] A second judgment module 440, configured to determine whether the grid to be connected meets the grid connection requirements when the deviation between the first voltage information and the second voltage information satisfies a preset deviation range.

[0117] The voltage information acquisition module 420 is further configured to perform a Fourier transform on the second voltage information to obtain a Fourier transform result; and obtain second voltage frequency information in the second voltage information according to the Fourier transform result.

[0118] A grid connection module 450, configured to connect the hydropower station to the grid to be connected when the grid to be connected meets the grid connection requirements.

[0119] Further, the second judgment module 440 includes a plurality of frequency value acquisition units, a type information judgment unit, and a judgment unit for determining whether the grid to be connected meets the grid connection requirements.

[0120] The plurality of frequency value acquisition units are configured to acquire second voltage frequency information in the second voltage information within a preset time to obtain a plurality of frequency values.

[0121] The type information judgment unit is configured to judge the type information of the grid to be connected according to the proportion of the plurality of frequency values within a reference frequency range. The type information judgment unit is further configured to judge that the grid to be connected is a large grid when the proportion of the plurality of frequency values within the reference frequency range meets a preset proportion requirement, and judge that the grid to be connected is a microgrid when the proportion of the plurality of frequency values within the reference frequency range does not meet the preset proportion requirement. The type information judgment unit is further configured to judge that the grid to be connected is a large grid when the proportion of the plurality of frequency values within the reference frequency range is greater than or equal to 50%, and judge that the grid to be connected is a microgrid when the proportion of the plurality of frequency values within the reference frequency range is less than 50%.

[0122] The judgment unit for determining whether the grid to be connected meets the grid connection requirements is configured to determine whether the grid to be connected meets the grid connection requirements according to the type information and the plurality of frequency values. The judgment unit for determining whether the grid to be connected meets the grid connection requirements is further configured to judge that the grid to be connected meets the grid connection requirements when the grid to be connected is a large grid;

[0123] When the grid to be connected is a microgrid and the plurality of frequency values not within the reference frequency range are all less than the first frequency endpoint value, judge that the grid to be connected meets the grid connection requirements;

[0124] When the grid to be connected is a microgrid and the plurality of frequency values not within the reference frequency range are all greater than the second frequency endpoint value, judge that the grid to be connected does not meet the grid connection requirements;

[0125] When the power grid to be interconnected is a microgrid and some of the multiple frequency values not within the reference frequency range are greater than the second frequency endpoint value and some are less than the first frequency endpoint value, it is determined that the power grid to be interconnected does not meet the grid connection requirements.

[0126] The grid connection module 450 is further configured to, after determining whether the power grid to be interconnected meets the grid connection requirements, if not, control the hydropower station to operate as an isolated grid.

[0127] In an embodiment of the present invention, a grid connection requirement information acquisition module is used to acquire grid connection requirement information, and a voltage information acquisition module is used to acquire relevant first voltage information and second voltage information. According to a first judgment module and a second judgment module, the relationship between the voltage information deviation and a preset deviation range is respectively judged. Based on the second judgment module, it is determined whether the power grid to be interconnected meets the grid connection requirements. Finally, the grid connection module is used to connect the hydropower station to the power grid to be interconnected that meets the grid connection requirements. The above diagnostic device for connecting a hydropower station to a power grid system can execute the diagnostic method for connecting a hydropower station to a power grid system provided in any embodiment of the present invention, and has function modules and beneficial effects corresponding to the execution of the method.

[0128] Embodiment Five

[0129] Figure 5 FIG. is a schematic structural diagram of a diagnostic device according to Embodiment Five of the present invention. The diagnostic device includes one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the diagnostic method for connecting a hydropower station to a power grid system provided in any embodiment of the present invention.

[0130] The diagnostic device is intended to represent various forms of digital computers, such as, a laptop computer, a desktop computer, a workbench, a personal digital assistant, a server, a blade server, a mainframe computer, and other suitable computers. The diagnostic device can also represent various forms of mobile devices, such as, a personal digital processor, a cellular phone, a smart phone, a wearable device (such as a helmet, glasses, a watch, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0131] As Figure 5As shown, the diagnostic device 10 includes at least one processor 11 and a memory communicatively connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc. The memory stores a computer program executable by the at least one processor. The processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the diagnostic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0132] Multiple components in the diagnostic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disc, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the diagnostic device 10 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0133] The processor 11 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the diagnostic method for a hydropower station integrating into the power grid system.

[0134] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A diagnostic method for a hydropower station to be incorporated into the power grid system, characterized in that, Including: Obtain the grid connection demand information of the hydropower station; Based on the grid connection demand information, obtain the first voltage information of the hydropower station and the second voltage information of the grid to be connected; Judge whether the deviation between the first voltage information and the second voltage information meets the preset deviation range; If so, judge whether the grid to be connected meets the grid connection requirements; If so, connect the hydropower station to the grid to be connected; Judging whether the grid to be connected meets the grid connection requirements includes: Within a preset time, obtain the second voltage frequency information in the second voltage information to obtain multiple frequency values; Judge the type information of the grid to be connected according to the proportion of multiple frequency values within the reference frequency range; Judge whether the grid to be connected meets the grid connection requirements according to the type information and multiple frequency values; Among them, the type information of the grid to be connected includes microgrid and large grid; The judging the type information of the grid to be connected according to the proportion of multiple frequency values within the reference frequency range includes: When the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, judge that the grid to be connected is a large grid; When the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, judge that the grid to be connected is a microgrid; The frequency values of the microgrid are different from those of the large grid; The reference frequency range includes a first frequency endpoint value and a second frequency endpoint value, and the first frequency endpoint value is less than the second frequency endpoint value; Judging whether the grid to be connected meets the grid connection requirements according to the type information and multiple frequency values includes: When the grid to be connected is a large grid, judge that the grid to be connected meets the grid connection requirements; When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all less than the first frequency endpoint value, judge that the grid to be connected meets the grid connection requirements; When the grid to be connected is a microgrid and multiple frequency values not within the reference frequency range are all greater than the second frequency endpoint value, judge that the grid to be connected does not meet the grid connection requirements; When the grid to be connected is a microgrid and some of the multiple frequency values not within the reference frequency range are greater than the second frequency endpoint value and some are less than the first frequency endpoint value, judge that the grid to be connected does not meet the grid connection requirements.

2. The diagnostic method according to claim 1, wherein When the proportion of multiple frequency values within the reference frequency range meets the preset proportion requirement, judging that the grid to be connected is a large grid includes: When the proportion of multiple frequency values within the reference frequency range is greater than or equal to 50%, judge that the grid to be connected is a large grid; When the proportion of multiple frequency values within the reference frequency range does not meet the preset proportion requirement, judging that the grid to be connected is a microgrid includes: When the proportion of multiple frequency values within the reference frequency range is less than 50%, judge that the grid to be connected is a microgrid.

3. The diagnostic method according to claim 1, wherein Obtaining the second voltage frequency information in the second voltage information includes: Perform Fourier transform on the second voltage information to obtain the Fourier transform result; According to the Fourier transform result, obtain the second voltage frequency information in the second voltage information.

4. The diagnostic method according to claim 1, characterized in that, After determining whether the power grid to be interconnected meets the interconnection requirements, it further includes: If not, control the hydropower station to operate in island mode.

5. The diagnostic method according to claim 1, characterized in that The first voltage information includes first voltage amplitude information, first voltage frequency information, and first voltage phase information; The second voltage information includes second voltage amplitude information, second voltage frequency information, and second voltage phase information; Determining whether the deviation between the first voltage information and the second voltage information meets a preset deviation range includes: Determining whether the deviation between the first voltage amplitude information and the second voltage amplitude information meets a preset amplitude deviation range; Determining whether the deviation between the first voltage frequency information and the second voltage frequency information meets a preset frequency deviation range; Determining whether the deviation between the first voltage phase information and the second voltage phase information meets a preset phase deviation range.

6. A diagnostic device for a hydropower station integrated into the power grid system, which is used to execute the diagnostic method for the hydropower station integrated into the power grid system according to any one of claims 1-5, characterized in that, It includes: An interconnection demand information acquisition module for acquiring the interconnection demand information of the hydropower station; A voltage information acquisition module for acquiring the first voltage information of the hydropower station and the second voltage information of the power grid to be interconnected based on the interconnection demand information; A first judgment module for judging whether the deviation between the first voltage information and the second voltage information meets a preset deviation range; A second judgment module for judging whether the power grid to be interconnected meets the interconnection requirements when the deviation between the first voltage information and the second voltage information meets a preset deviation range; An interconnection module for interconnecting the hydropower station to the power grid to be interconnected when the power grid to be interconnected meets the interconnection requirements.

7. A diagnostic device, characterized in that, The diagnostic device includes: One or more processors; A storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the diagnostic method for the hydropower station grid connection system as described in any one of claims 1-5.

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