Offshore oil and gas field power grid frequency index determination method suitable for wind power integration

Abstract

The invention provides an offshore oil and gas field power grid frequency index determination method suitable for wind power integration, and relates to the technical field of micro-grids, and the method comprises the steps: according to the rated power of each generator set started in a power generation system of an offshore oil and gas field power grid, a speed regulator proportionality coefficient, a prime motor time constant, an inertia time constant and a damping coefficient; determining equivalent parameters of the power generation system, wherein the equivalent parameters comprise a speed regulator proportionality coefficient, a prime mover time constant, an inertia time constant and a damping coefficient; and determining an output frequency index of the power generation system based on the equivalent parameter and the operation parameter of the wind turbine generator connected to the offshore oil and gas field power grid, wherein the output frequency index comprises the maximum frequency deviation and the steady-state frequency deviation. According to the method, frequency index quantitative analysis of the offshore oil and gas field power grid with wind power added can be realized.

Description

Technical Field

[0001] The present invention relates to the field of microgrids, and in particular to a method for determining frequency indicators of offshore oil and gas field power grids suitable for wind power access. Background Art

[0002] As an integrated oil and gas production, gathering, and transportation system, offshore oil and gas fields typically rely on gas- or oil-fired generators deployed on multiple platforms to generate, gather, and transport oil and gas. When offshore wind turbines are connected to the grid, the platform's functional system transforms from a single, isolated system to a multi-energy system, operating in tandem with wind power and gas / oil turbine generators. This system is a wind-, gas-, and oil-based, synergistic energy supply system. Excess oil and gas are then pumped and compressed, then transported by ship or pipeline.

[0003] The operation of offshore wind turbines is influenced by the weather and inherently uncertain. Once offshore wind power is connected to the grid, turbine generators become the sole power source to mitigate wind power's uncertainties. In off-grid operation, the offshore platform cluster's energy system, powered by offshore wind power and the turbine generators, achieves energy self-sufficiency through the combination of offshore wind power and turbine generators. During periods of low offshore wind power, power is primarily supplied by turbine generators, consuming self-produced natural gas and crude oil. During peak periods, turbine generators reduce output to maximize wind power consumption.

[0004] When offshore wind power, a resource with uncertainties, is connected to the grid of a functioning offshore oil and gas platform, the impact of frequency fluctuations caused by wind power integration must be considered when smoothing frequency fluctuations, as the energy demand of offshore oil and gas platforms fluctuates relatively little. However, existing techniques for analyzing output frequency fluctuations in offshore oil and gas field power generation systems primarily apply to conventional offshore oil and gas platforms, and there is no quantitative analysis method for output frequency indicators specifically for offshore oil and gas field grids connected to wind power. Summary of the Invention

[0005] The present invention provides a method for determining the frequency index of an offshore oil and gas field power grid suitable for wind power access, so as to overcome the defect in the prior art that there is no method for analyzing the output frequency fluctuation index of an offshore oil and gas field power grid connected to wind power, and realize the output frequency index fluctuation analysis of an offshore oil and gas field power grid suitable for wind power access.

[0006] The present invention provides a method for determining frequency indicators of offshore oil and gas field power grids applicable to wind power access, the method comprising: Determining equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient; The output frequency index of the power generation system is determined based on the equivalent parameters and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid. The output frequency index includes the maximum frequency deviation when the wind turbine generator set is in normal operating state, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine generator set is in a fault-offline state.

[0007] According to a method for determining a frequency index of an offshore oil and gas field grid applicable to wind power access provided by the present invention, the method determines the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field grid, including: The maximum frequency deviation of the wind turbine generator set when it is in normal operation is determined based on a first preset formula, where the first preset formula is: ; in, represents the maximum frequency deviation of the power generation system when the wind turbine is in normal operation. It represents the fluctuation ratio of the wind power of the wind turbine in unit time, , represents the governor proportional coefficient in the equivalent parameters of the power generation system, and D represents the damping coefficient in the equivalent parameters of the power generation system.

[0008] According to a method for determining a frequency index of an offshore oil and gas field grid applicable to wind power access provided by the present invention, the method determines the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field grid, including: The maximum frequency deviation of the wind turbine generator set when it is in a grid-off fault state is determined based on a second preset formula, where the second preset formula is: ; ; ; ; , ; in, represents the maximum frequency deviation of the power generation system when the wind turbine is in a grid-off fault state, represents the upper limit of the output power of the wind turbine, H and D represent the inertia time constant and damping coefficient in the equivalent parameters of the power generation system respectively, represents the prime mover constant among the equivalent parameters of the power generation system, , It represents the governor proportional coefficient in the equivalent parameters of the power generation system.

[0009] According to a method for determining a frequency index of an offshore oil and gas field grid applicable to wind power access provided by the present invention, the method determines the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field grid, including: The steady-state frequency deviation of the wind turbine generator set when it is in a grid-off fault state is determined based on a third preset formula, wherein the third preset formula is: ; in, represents the steady-state frequency deviation of the power generation system when the wind turbine is in a grid-off fault state, Indicates the upper limit of the output power of the wind turbine generator set, , represents the governor proportional coefficient in the equivalent parameters of the power generation system, and D represents the damping coefficient in the equivalent parameters of the power generation system.

[0010] According to the present invention, a method for determining a frequency index of an offshore oil and gas field grid applicable to wind power access is provided. After determining the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field grid, the method includes: Based on the output frequency index of the power generation system, an operation constraint condition of the power generation system is constructed, and the operation constraint condition is used to adjust the scheduling plan of the offshore oil and gas field power grid.

[0011] According to a method for determining a frequency index of an offshore oil and gas field power grid applicable to wind power access provided by the present invention, the operating constraints of the power generation system are constructed based on the output frequency index of the power generation system, including: Constructing a constraint condition function that the maximum frequency deviation of the wind turbine generator set when it is in a grid-off fault state is less than a maximum frequency deviation threshold; The constraint condition function is converted into a quadratic convex constraint function with respect to an inertia time constant in the equivalent parameters of the power generation system and an inter-motor constant in the equivalent parameters of the power generation system.

[0012] The present invention also provides a device for determining frequency index of an offshore oil and gas field power grid suitable for wind power access, the device comprising: an equivalent parameter determination module, configured to determine equivalent parameters of the power generation system according to the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient; A frequency index determination module is used to determine the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine group connected to the offshore oil and gas field power grid, wherein the output frequency index includes a maximum frequency deviation and a steady-state frequency deviation.

[0013] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for determining the frequency index of an offshore oil and gas field power grid applicable to wind power access as described above is implemented.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for determining the frequency index of an offshore oil and gas field power grid applicable to wind power access as described in any of the above is implemented.

[0015] The present invention also provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the above-described methods for determining frequency indicators of offshore oil and gas field power grids applicable to wind power access.

[0016] The present invention provides a method for determining frequency indicators of offshore oil and gas field power grids suitable for wind power access. The method determines equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid. The equivalent parameters include the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient. Based on the equivalent parameters of the power generation system and the operating parameters of the wind turbines connected to the offshore oil and gas field power grid, the frequency indicators of the power generation system, including the maximum frequency deviation and the steady-state frequency deviation, are determined, thereby realizing quantitative analysis of the frequency indicators of the offshore oil and gas field power grid connected to wind power. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1The present invention provides a flow chart of a method for determining frequency indicators of offshore oil and gas field power grids applicable to wind power access.

[0019] Figure 2 It is a structural schematic diagram of an experimental system for a method for determining frequency indicators of offshore oil and gas field power grids applicable to wind power access provided by the present invention.

[0020] Figure 3 This is an experimental demonstration of the method for determining the frequency index of offshore oil and gas field power grids applicable to wind power access provided by the present invention. Figure 1 .

[0021] Figure 4 This is an experimental demonstration of the method for determining the frequency index of offshore oil and gas field power grids applicable to wind power access provided by the present invention. Figure 2 .

[0022] Figure 5 This is an experimental demonstration of the method for determining the frequency index of offshore oil and gas field power grids applicable to wind power access provided by the present invention. Figure 3 .

[0023] Figure 6 The present invention provides a schematic structural diagram of a device for determining frequency indexes of offshore oil and gas field power grids suitable for wind power access.

[0024] Figure 7 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0026] The following combination Figure 1-5 The present invention provides a method for determining the frequency index of an offshore oil and gas field power grid suitable for wind power access. Figure 1 As shown, the method for determining the frequency index of an offshore oil and gas field power grid applicable to wind power access provided by the present invention comprises the following steps: S110, determining equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient; S120. Determine an output frequency index of the power generation system based on equivalent parameters and operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid. The output frequency index includes a maximum frequency deviation when the wind turbine generator set is in a normal operating state, and a maximum frequency deviation and a steady-state frequency deviation when the wind turbine generator set is in a fault-offline state.

[0027] In the method provided by the present invention, the power generation system of an offshore oil and gas field power grid includes multiple generator sets and is connected to wind power. The generator sets are turbine generator sets, which can be oil-fired or gas-fired. The frequency model of the generator set can be considered a combination of a speed governor, a prime mover, and a synchronous generator. That is, the frequency of the generator set is related to the parameters of the speed governor, prime mover, and synchronous generator, which together constitute the frequency response dynamics of the generator set. In actual operation, multiple generator sets may be partially turned on and partially turned off. For the activated generator sets, the method provided by the present invention treats all activated generator sets as an aggregated frequency response model, whose corresponding equivalent parameters include the speed governor proportional parameter, prime mover time constant, inertia time constant, and damping coefficient. That is, for each individual generator set, its speed governor proportional parameter, prime mover time constant, inertia time constant, and damping coefficient are fixed. However, in the method provided by the present invention, all activated generator sets are treated as an aggregated generator set, and the frequency change is determined based on the speed governor proportional parameter, prime mover time constant, inertia time constant, and damping coefficient of this aggregated generator set.

[0028] Specifically, the calculation process of each equivalent parameter of the power generation system in the offshore oil and gas field power grid can be expressed as follows: ; ; ; ; Where H and D represent the inertia time constant and damping coefficient of the equivalent parameters of the power generation system in the offshore oil and gas field power grid, respectively; is the collection of gas / oil generator sets in OPCES, and ; Indicates a turbine generator set The start and stop status of the generator set, such as At startup, ,otherwise ; and Indicates a generator set The inertia time constant and damping coefficient of the synchronous generator; s is the Laplace operator, Indicates a generator set Rated power, Represents the governor proportional coefficient in the equivalent parameters of the power generation system in the offshore oil and gas field power grid; Represents the prime mover constant in the equivalent parameters of the power generation system in the offshore oil and gas field power grid; Indicates a turbine generator set The proportional coefficient of the speed regulator; Indicates a turbine generator set The time constant of the prime mover.

[0029] In an offshore oil and gas field power grid connected to wind power, due to the strong volatility of wind power, the output frequency of the power generation system of the offshore oil and gas field power grid will change in response to changes in wind power output. In order to ensure that the fluctuation of the output frequency of the power generation system of the offshore oil and gas field power grid is smoothed, it is necessary to determine the various output frequency indicators of the power generation system of the offshore oil and gas field when the output power of the wind turbine changes, and then quantitatively analyze these output frequency indicators to determine whether these output frequency indicators meet the operating requirements of the offshore oil and gas field power grid, and then modify the scheduling plan of the offshore oil and gas field power grid, such as modifying the start and stop status of the engine group in the offshore oil and gas field power grid, modifying the configuration parameters of the wind turbine in the offshore oil and gas field power grid, and modifying the configuration parameters of the generator group in the offshore oil and gas field power grid.

[0030] There are two operating states for wind turbines connected to offshore oil and gas field power grids: normal operating state and fault-off-grid state. In normal operating state, the power supply of the wind turbine will fluctuate but will not disappear directly. In fault-off-grid state, the power supply of the wind turbine will be disconnected from the grid, that is, it will not supply power to the offshore oil and gas field power grid.

[0031] Output frequency indicators include the maximum frequency deviation when the wind turbine is operating normally, and the maximum and steady-state frequency deviations when the wind turbine is disconnected from the grid due to a fault. The following describes the specific calculation methods and formula derivation for these three output frequency indicators.

[0032] The generator set includes a synchronous generator, a prime mover, and a speed regulator. The rotor motion equation of the synchronous generator can be expressed as: ; in, Indicates the initial value of the mechanical power output of the prime mover of the power generation system, Indicates wind power output change information, Indicates the load of the offshore oil and gas field power grid.

[0033] The generator set's speed regulator uses a PI controller to achieve both differential and fixed frequency regulation. Since offshore oil and gas field power grid generators currently use digital speed regulators with millisecond-level response capabilities, the delay of the frequency regulation command can be ignored. The prime mover's response process is described by a first-order inertia link. Therefore, the prime mover output power change model caused by frequency deviation can be expressed as: .

[0034] In view of the two different states of offshore wind turbines during operation, wind power fluctuation models are modeled to simulate wind power fluctuations under normal operating conditions and power mutations when wind power is disconnected from the grid under fault conditions. Specifically,

[0035] When a wind turbine connected to an offshore oil and gas field grid operates normally, due to the volatility of wind power, the output power fluctuation model of the wind turbine is: .

[0036] When a wind turbine connected to an offshore oil and gas field grid fails and goes offline, the output power fluctuation model of the wind turbine is: .

[0037] in, Indicates the wind power output change information, Indicates the fluctuation ratio of wind power per unit time, represents the time constant of offshore wind power, Indicates the upper limit of wind power output power connected to the offshore oil and gas field power grid, represents the Laplace operator.

[0038] Based on the model given above, the frequency domain expression of the frequency change of the offshore oil and gas field power generation system caused by fluctuations during normal operation of the wind turbine can be obtained as follows: ; .

[0039] Since the inertia time constant of the synchronous generator set and the prime mover time constant have negligible effects on the transient process of the frequency response, the frequency response model of the offshore oil and gas field power grid connected to wind power under normal operating conditions of the wind turbine can be simplified as follows: .

[0040] Based on the frequency domain expression of the frequency change of the offshore oil and gas field power grid power generation system under normal operation of the wind turbine, the maximum frequency deviation calculation formula of the power generation system when the wind turbine of the offshore oil and gas field power grid is operating normally can be obtained. That is, the output frequency index of the power generation system is determined based on the equivalent parameters and the operating parameters of the wind turbine connected to the offshore oil and gas field power grid, including: The maximum frequency deviation of the wind turbine generator set when it is in normal operation is determined based on a first preset formula. The first preset formula is: ; in, It indicates the maximum frequency deviation of the power generation system when the wind turbine is in normal operation. It represents the fluctuation ratio of wind power of wind turbine in unit time. , It represents the governor proportional coefficient in the equivalent parameters of the power generation system, and D represents the damping coefficient in the equivalent parameters of the power generation system.

[0041] The frequency domain expression of the frequency change caused by the wind turbine failure and disconnection from the grid is: ; ; ; Transfer function The damping ratio is: .

[0042] because , so in actual operation, we can Approximately equal to D.

[0043] In offshore oil and gas fields, , , , we can get ,therefore, It is an underdamped system.

[0044] Based on the frequency domain expression of the frequency change of the wind turbine in the offshore oil and gas field grid when the wind turbine fails and is disconnected from the grid, the maximum frequency deviation calculation formula of the power generation system when the wind turbine fails and is disconnected from the grid can be obtained. That is, the output frequency index of the power generation system is determined based on the equivalent parameters and the operating parameters of the wind turbine connected to the offshore oil and gas field grid, including: The maximum frequency deviation when the wind turbine generator set is in a grid-off fault state is determined based on a second preset formula. The second preset formula is: ; ; ; ; , ; in, Indicates the maximum frequency deviation of the power generation system when the wind turbine is in a faulty and disconnected state. represents the upper limit of the output power of the wind turbine, H and D represent the inertia time constant and damping coefficient in the equivalent parameters of the power generation system respectively. represents the prime mover constant in the equivalent parameters of the power generation system, , Indicates the governor proportional coefficient in the equivalent parameters of the power generation system, The time when the frequency is the lowest.

[0045] When the wind turbine is in a fault-off-grid state, the steady-state frequency deviation expression of the power generation system is: ; in, It indicates the steady-state frequency deviation of the power generation system when the wind turbine is in a faulty and disconnected state.

[0046] According to the above-mentioned method for determining the frequency index, the frequency index value of the offshore oil and gas field platform during operation can be determined based on the operating parameters of the offshore oil and gas field platform, including the operating parameters of the wind turbine, the parameters of the generator, and the start and stop status of the generator, so as to determine whether the frequency index value corresponding to the operating parameters of the offshore oil and gas field platform can meet the requirements, and adjust the scheduling plan of the offshore oil and gas field platform, such as adjusting the start and stop status of the generator and adjusting the parameters of the started generator. That is, after determining the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine connected to the offshore oil and gas field power grid, it includes: Based on the output frequency index of the power generation system, the operation constraints of the power generation system are constructed.

[0047] Operational constraints can constrain the effectiveness of scheduling plans for offshore oil and gas field power grids. In other words, scheduling plans for power generation systems can be determined based on these operational constraints. Of course, it is understood that operational constraints can be constructed based on other indicators besides output frequency.

[0048] Specifically, considering the two operating conditions of wind turbines, the constraint condition for the impact of wind power uncertainty on the output frequency of the power generation system can be expressed as: ; ; ; Where, for The upper boundary of . for The upper boundary of . for The upper limit of the limit can be set according to the actual situation.

[0049] From the front The calculation formula of is known, For H and A strong nonlinear function, in order to facilitate the scheduling, a commercial solver such as GUROBI can be used for solution. In the method provided by the present invention, Transformed into about H and The quadratic convex constraint is constructed based on the output frequency index of the power generation system, which includes: Construct a constraint function that the maximum frequency deviation of the wind turbine generator set is less than the maximum frequency deviation threshold when the wind turbine generator set is in a grid-off fault state; The constraint condition function is transformed into a quadratic convex constraint function about the inertia time constant in the equivalent parameters of the power generation system and the prime mover constant in the equivalent parameters of the power generation system.

[0050] Will Transformed into about H and The result of the quadratic convex constraint can be expressed as: ; in, 、 、 、 、 、 are fitting parameters, which can be obtained by pre-fitting calculation.

[0051] The method provided by the present invention provides a method for quantifying frequency indicators during normal operation of offshore wind power and a method for quantifying step frequency indicators when offshore wind power is off-grid. At the same time, the constraint conditions of the two different operating conditions are integrally constructed, and finally the transfer function is converted into a quadratic convex model to adapt to conventional commercial solvers for solution calculations.

[0052] In order to verify the correctness and effectiveness of the method provided by the present invention, the present invention takes a certain offshore oil and gas field as an example for verification. The system structure of the offshore oil and gas field is as follows: Figure 2As shown in the figure, the offshore oil and gas field system consists of four interconnected offshore oil and gas platforms. Platforms A1 and A2 form one production unit, and platforms B1 and B2 form another. The two production units are interconnected by a 15 km cable to ensure overall power supply reliability. The offshore oil and gas field is equipped with a gas compressor (C1) and two oil transfer pumps (P1-P2) rated at 1000 kW. To meet power supply requirements, a total of nine generator sets are deployed, including two gas-fired generator sets (G1-G2) and seven oil-fired generator sets (G3-G9). Offshore wind turbines can be connected to the platform grid via platform A1.

[0053] In a microgrid power system consisting of an offshore oil and gas platform with offshore wind power access, the speed regulators of all turbine generator sets are set with the same proportional coefficient. When KP=25, The fitting results are as follows Figure 3 shown. Figure 3 For the fitted surface and the original surface, as well as different H and The fitting error when . Figure 4 The distribution characteristics of the fitting error are shown in Figure 2. It can be seen that 95% of the fitting errors are within 2.0% and 50% of the fitting errors are within 0.7%. Therefore, when KP=25, the distribution characteristics of H and A quadratic polynomial that can be used for nonlinear surfaces It has a good fitting effect.

[0054] When the governor proportional coefficient KP takes different values, The maximum fitting error is Figure 5 As shown. It can be seen that when the proportional coefficient of the speed regulator is different The maximum fitting error of does not exceed 3.23%. Therefore, for different speed regulator proportional coefficients, the The quadratic polynomials can be used for nonlinear surfaces Has a good fitting effect, such as Figure 5 shown.

[0055] The following describes the device for determining the frequency index of an offshore oil and gas field grid suitable for wind power access provided by the present invention. The device for determining the frequency index of an offshore oil and gas field grid suitable for wind power access described below and the method for determining the frequency index of an offshore oil and gas field grid suitable for wind power access described above can be used for reference. Figure 6 As shown, the device for determining frequency index of offshore oil and gas field power grid applicable to wind power access provided by the present invention includes the following modules: an equivalent parameter determination module 610 for determining equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient; The frequency index determination module 620 is used to determine the output frequency index of the power generation system based on equivalent parameters and the operating parameters of the wind turbine connected to the offshore oil and gas field power grid. The output frequency index includes the maximum frequency deviation when the wind turbine is in normal operation, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine is in a fault and disconnected state.

[0056] Figure 7 An example of a physical structure diagram of an electronic device is shown below. Figure 7 As shown, the electronic device may include: a processor 710, a communications interface 720, a memory 730, and a communications bus 740, wherein the processor 710, the communications interface 720, and the memory 730 communicate with each other via the communications bus 740. The processor 710 may call logic instructions in the memory 730 to execute a method for determining a frequency index of an offshore oil and gas field power grid suitable for wind power access. The method includes: determining equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant, and damping coefficient; and determining an output frequency index of the power generation system based on the equivalent parameters and operating parameters of the wind turbines connected to the offshore oil and gas field power grid, the output frequency index including the maximum frequency deviation when the wind turbine is in normal operation, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine is in a fault-offline state.

[0057] Furthermore, the logic instructions in the aforementioned memory 730 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0058] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the method for determining the frequency index of an offshore oil and gas field power grid suitable for wind power access provided by the above methods. The method includes: determining the equivalent parameters of the power generation system based on the rated power, speed regulator proportional coefficient, prime mover time constant, inertia time constant and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the speed regulator proportional coefficient, prime mover time constant, inertia time constant and damping coefficient; determining the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine set connected to the offshore oil and gas field power grid, the output frequency index including the maximum frequency deviation when the wind turbine set is in normal operating state, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine set is in a fault-offline state.

[0059] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for determining a frequency index of an offshore oil and gas field power grid suitable for wind power access provided by the above-mentioned methods, the method comprising: determining equivalent parameters of the power generation system based on the rated power, governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, the equivalent parameters including the governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient; determining the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine set connected to the offshore oil and gas field power grid, the output frequency index including the maximum frequency deviation when the wind turbine set is in normal operating state, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine set is in a fault-offline state.

[0060] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0061] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for determining frequency index of offshore oil and gas field power grid suitable for wind power access, characterized in that: The method comprises: Determine equivalent parameters of the power generation system according to the rated power, governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, wherein the equivalent parameters include the governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient; The output frequency index of the power generation system is determined based on the equivalent parameters and the operating parameters of the wind turbine group connected to the offshore oil and gas field power grid. The output frequency index includes the maximum frequency deviation when the wind turbine group is in normal operating state, and the maximum frequency deviation and steady-state frequency deviation when the wind turbine group is in a fault-off-grid state.

2. The method for determining frequency index of offshore oil and gas field power grid suitable for wind power access according to claim 1 is characterized in that: The step of determining the output frequency index of the power generation system based on the equivalent parameter and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid includes: The maximum frequency deviation of the wind turbine generator set when it is in normal operation is determined based on a first preset formula, where the first preset formula is: ； in, represents the maximum frequency deviation of the power generation system when the wind turbine is in normal operation, It represents the fluctuation ratio of the wind power of the wind turbine in unit time, , represents the governor proportional coefficient in the equivalent parameters of the power generation system, and D represents the damping coefficient in the equivalent parameters of the power generation system.

3. The method for determining frequency index of offshore oil and gas field power grid suitable for wind power access according to claim 1, characterized in that: The step of determining the output frequency index of the power generation system based on the equivalent parameter and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid includes: The maximum frequency deviation when the wind turbine generator set is in an off-grid fault state is determined based on a second preset formula, where the second preset formula is: ； ； ； ； ， ； in, represents the maximum frequency deviation of the power generation system when the wind turbine is in a grid-off fault state, represents the upper limit of the output power of the wind turbine, H and D represent the inertia time constant and damping coefficient in the equivalent parameters of the power generation system respectively, represents the prime mover constant among the equivalent parameters of the power generation system, , It represents the governor proportional coefficient in the equivalent parameters of the power generation system.

4. The method for determining frequency index of offshore oil and gas field power grid suitable for wind power access according to claim 1, characterized in that: The step of determining the output frequency index of the power generation system based on the equivalent parameter and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid includes: The steady-state frequency deviation of the wind turbine generator set when it is in a grid-off fault state is determined based on a third preset formula, wherein the third preset formula is: ； in, represents the steady-state frequency deviation of the power generation system when the wind turbine is in a grid-off fault state, represents the upper limit of the output power of the wind turbine generator set, , represents the governor proportional coefficient in the equivalent parameters of the power generation system, and D represents the damping coefficient in the equivalent parameters of the power generation system.

5. The method for determining frequency index of offshore oil and gas field power grid applicable to wind power access according to claim 3 is characterized in that: After determining the output frequency index of the power generation system based on the equivalent parameter and the operating parameters of the wind turbine generator set connected to the offshore oil and gas field power grid, the method includes: Based on the output frequency index of the power generation system, an operation constraint condition of the power generation system is constructed, and the operation constraint condition is used to adjust the scheduling plan of the offshore oil and gas field power grid.

6. The method for determining frequency index of offshore oil and gas field power grid applicable to wind power access according to claim 5, characterized in that: The step of constructing the operation constraint condition of the power generation system based on the output frequency index of the power generation system includes: Constructing a constraint condition function that the maximum frequency deviation of the wind turbine generator set when it is in a grid-off fault state is less than a maximum frequency deviation threshold; The constraint condition function is converted into a quadratic convex constraint function about the inertia time constant in the equivalent parameters of the power generation system and the prime mover inter-constant in the equivalent parameters of the power generation system.

7. A device for determining frequency index of offshore oil and gas field power grid suitable for wind power access, characterized in that: The device comprises: An equivalent parameter determination module is used to determine the equivalent parameters of the power generation system according to the rated power, governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient of each generator set started in the power generation system of the offshore oil and gas field power grid, wherein the equivalent parameters include the governor proportional coefficient, prime mover time constant, inertia time constant and damping coefficient; The frequency index determination module is used to determine the output frequency index of the power generation system based on the equivalent parameters and the operating parameters of the wind turbine group connected to the offshore oil and gas field power grid, and the output frequency index includes a maximum frequency deviation and a steady-state frequency deviation.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for determining the frequency index of an offshore oil and gas field power grid applicable to wind power access as described in any one of claims 1 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for determining frequency index of an offshore oil and gas field power grid applicable to wind power access as claimed in any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for determining frequency index of an offshore oil and gas field power grid applicable to wind power access as claimed in any one of claims 1 to 6 is implemented.

Images