System for reducing the effects of voltage sags using compressor determination method, medium, and system

Abstract

The application discloses a kind of system for reducing the influence of voltage sag compressor determination method, medium and system, the method comprises: the compressor site selection coefficient corresponding to the grid node and natural gas grid node of compressor access in electric-gas integrated energy system is calculated;The grid node and natural gas grid node corresponding to the highest compressor site selection coefficient are determined as the grid node and natural gas grid node of compressor access;The best capacity of compressor is calculated;The compressor is accessed in the grid node and natural gas grid node of compressor access, and make compressor run at the best capacity.The embodiment of the application takes economy as the goal, considers equipment cost, operation and maintenance and installation cost at the same time, optimizes the configuration of compressor in electric-gas integrated energy system, to prevent the purpose of the influence of voltage sag on natural gas, effectively reduce the loss of load shedding of natural gas system caused by voltage sag.

Description

Technical Field

[0001] This invention relates to the field of voltage sag technology, and more particularly to a method, medium, and system for determining a compressor to reduce the effects of voltage sag. Background Technology

[0002] With the increasing scarcity of fossil fuels and the growing severity of environmental problems, energy transition has become an inevitable path for the sustainable development of the economy and society. Integrated electricity-gas energy systems are of great significance for promoting the large-scale development of renewable energy, improving energy efficiency, increasing the utilization rate of social infrastructure, ensuring energy security, and achieving energy conservation and emission reduction. However, while achieving these goals, integrated electricity-gas energy systems also face serious problems. Due to the close coupling of integrated electricity-gas energy systems, a "trigger system" effect can occur. On the one hand, a natural gas system failure will affect the power system, and on the other hand, a power system failure will also affect the natural gas system. Currently, voltage sag has become the most serious power quality problem, causing great distress to various sensitive users. Therefore, it is necessary to study the voltage sag problem. Due to the presence of coupling equipment in integrated electricity-gas energy systems, voltage sag can affect the natural gas system through coupling equipment failures. That is, once a voltage sag event occurs, the power system is affected and suffers losses, while the natural gas system also suffers losses due to coupling equipment failure. Current technology lacks methods to prevent integrated electricity-gas energy systems from being affected by voltage sags. Summary of the Invention

[0003] This invention provides a method, medium, and system for determining a system compressor to reduce the impact of voltage sags, thereby addressing the lack of technical solutions in the prior art for preventing voltage sags in integrated electric-gas energy systems.

[0004] In a first aspect, a method for determining a system compressor to reduce the effects of voltage sags is provided, comprising:

[0005] Calculate the compressor location coefficients for the grid nodes and natural gas grid nodes to which the compressors are connected in the integrated electric-gas energy system;

[0006] The power grid node and natural gas network node corresponding to the highest compressor location coefficient are determined as the power grid node and natural gas network node to which the compressor is connected;

[0007] Calculate the optimal capacity of the compressor;

[0008] The compressor is connected to the power grid node and the natural gas grid node, and the compressor is operated at the optimal capacity.

[0009] In a second aspect, a computer-readable storage medium is provided, wherein computer program instructions are stored thereon; when executed by a processor, the computer program instructions implement the system compressor determination method for reducing the effects of voltage sags as described in the first aspect embodiment above.

[0010] Thirdly, a compressor determination system for reducing the effects of voltage sags is provided, comprising: a computer-readable storage medium as described in the second aspect embodiment above.

[0011] Thus, this embodiment of the invention, with economic efficiency as the goal, comprehensively considers equipment costs, operation and maintenance and installation costs, and optimizes the configuration of the compressor in the electric-gas integrated energy system, thereby achieving the purpose of preventing the impact of voltage dips on natural gas and effectively reducing the load shedding loss of the natural gas system caused by voltage dips. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart of a method for determining a system compressor to reduce the impact of voltage sag, according to an embodiment of the present invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] This invention discloses a method for determining system compressor parameters to reduce the impact of voltage sags. This method is used to reduce the losses caused by voltage sags in natural gas systems by determining compressor parameters. Figure 1 As shown, the method includes the following steps:

[0016] Step S1: Calculate the compressor location coefficients corresponding to the grid nodes and natural gas grid nodes to which the compressors are connected in the integrated electric-gas energy system.

[0017] In an integrated electric-gas energy system, the compressor acts as a coupling device between the power and natural gas systems. Therefore, since the compressor is part of both systems, a voltage sag directly impacts the power system while simultaneously causing losses to the natural gas system due to the coupling device. Because the compressor requires power, a voltage sag can cause it to malfunction. Furthermore, in the natural gas network, the compressor ensures that the gas pressure is normal when it is transmitted to the load side; a compressor failure will lead to a loss of load in the natural gas system. Therefore, the location of the compressor must be considered in conjunction with both systems. The purpose of compressor location selection is to reduce the load shedding losses caused by voltage sags in the natural gas system, but it is also necessary to comprehensively consider the compressor's annual installation and maintenance costs to maximize its overall annual benefits.

[0018] The mitigating effect of compressor connection location on voltage sag events in the natural gas system depends on the frequency of voltage sag failures at the grid connection point, the distance between the grid connection point and the natural gas grid connection point, and the load connected downstream of the natural gas grid connection point. A lower frequency of voltage sag failures at the grid connection point to which the compressor is connected, and a more advantageous location; similarly, a location with minimal load shedding due to faults at the gas grid connection point to which the compressor is connected, is also more advantageous. However, since connecting the grid and gas grid requires installation and maintenance costs, the greater the distance, the higher the cost. Therefore, it is necessary to comprehensively consider all three factors.

[0019] Based on this, a compressor location factor is defined to evaluate the compressor installation location. Specifically, the formula for calculating the compressor location factor is:

[0020]

[0021] Where α represents the compressor location factor, d ij d represents the distance between the grid node to which the compressor is connected and the natural gas grid node; n represents the annual number of compressor failures caused by voltage sags; N represents the annual number of voltage sags at the grid node to which the compressor is connected; e represents the annual average of the natural gas grid load shedding value caused by voltage sags; and E represents the total load value of other nodes in the natural gas grid downstream of the natural gas grid node to which the compressor is connected. ij This can be obtained through measurement. n, N, and e can be obtained by statistically analyzing historical records. For N, each time the voltage falls below the compressor's tolerance level, it is recorded as a fault. For n, N, and e, the average of multiple years' data can be used; the number of years can be determined based on the actual situation. E can be obtained by summing the loads required by the corresponding nodes.

[0022] Step S2: Determine the grid node and natural gas grid node corresponding to the highest compressor location coefficient as the grid node and natural gas grid node to which the compressor is connected.

[0023] Since a higher compressor location factor indicates a more favorable installation location, the power grid node and natural gas network node corresponding to the highest compressor location factor are selected as the power grid node and natural gas network node to which the compressor is connected.

[0024] Step S3: Calculate the optimal capacity of the compressor.

[0025] This step includes the following process:

[0026] (1) Construct the compressor cost loss function.

[0027] Once the power grid nodes and natural gas network nodes connected to the compressor are determined, the compressor needs to be rated for capacity. During natural gas transmission through pipelines, pressure may decrease due to friction and other factors. The compressor's role is to increase this pressure, ensuring that the natural gas reaches the load at the correct pressure. Therefore, its capacity must be sufficient to meet the load pressure requirements of the connected natural gas network within its normal range. However, its capacity should not be too small or too large. Too small a capacity will result in insufficient margin, making the compressor susceptible to load slippage and losses. Too large a capacity will increase investment and maintenance costs. To ensure optimal economic efficiency—that is, minimizing costs, maintenance expenses, and losses due to voltage sags—a compressor cost loss function is constructed.

[0028] Specifically, the compressor cost loss function is as follows:

[0029]

[0030] Where LimY represents compressor cost loss, β represents the ratio of annual compressor operation and maintenance costs to compressor cost, W represents compressor capacity, W0 represents the minimum compressor capacity required to ensure normal operation of the natural gas network, and C a C represents the unit capacity cost of the compressor. b This represents the compressor's unit capacity loss due to load shedding. Compressor cost losses generally include compressor operation and maintenance costs, compressor costs, and compressor losses due to voltage dips. Compressor costs generally include the cost of purchasing and installing the compressor. The compressor's unit capacity cost can be obtained from literature and / or the compressor nameplate, while the compressor's unit capacity loss due to load shedding can be obtained from historical data.

[0031] (2) The compressor capacity corresponding to the minimum value of the compressor cost loss function is determined as the optimal capacity of the compressor.

[0032] That is, the W corresponding to the minimum LimY is the optimal capacity of the compressor.

[0033] Step S4: Connect the compressor to the grid node and the natural gas grid node, and operate the compressor at its optimal capacity.

[0034] This invention also discloses a computer-readable storage medium storing computer program instructions; when executed by a processor, the computer program instructions implement the system compressor determination method for reducing the impact of voltage sags as described in the above embodiments.

[0035] This invention also discloses a compressor determination system for reducing the effects of voltage sags, comprising: a computer-readable storage medium as described in the above embodiments.

[0036] In summary, the embodiments of the present invention, with economic efficiency as the goal, comprehensively consider equipment costs, operation and maintenance and installation costs, and optimize the configuration of the compressor in the electric-gas integrated energy system, thereby achieving the purpose of preventing the impact of voltage sag on natural gas and effectively reducing the load shedding loss of the natural gas system caused by voltage sag.

[0037] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for determining a compressor in a system to reduce the effects of voltage sags, characterized in that, include: Calculate the compressor location coefficients for the grid nodes and natural gas grid nodes to which the compressors are connected in the integrated electric-gas energy system; The power grid node and natural gas network node corresponding to the highest compressor location coefficient are determined as the power grid node and natural gas network node to which the compressor is connected; Calculate the optimal capacity of the compressor; The compressor is connected to both the power grid node and the natural gas grid node, and the compressor is operated at the optimal capacity. The formula for calculating the compressor location factor is: ； in, α This represents the compressor location factor. d ij This indicates the distance between the power grid node to which the compressor is connected and the natural gas grid node. n This indicates the number of compressor failures per year caused by voltage dips. N This indicates the number of voltage dips per year at the grid node to which the compressor is connected. e This represents the annual average of the load shedding value of the natural gas network caused by voltage dips. E This represents the total load of other nodes in the natural gas network downstream of the node to which the compressor is connected.

2. The method for determining a system compressor to reduce the effects of voltage sags according to claim 1, characterized in that, The steps for calculating the optimal capacity of the compressor include: Construct the compressor cost loss function; The compressor capacity corresponding to the minimum value of the compressor cost loss function is determined as the optimal capacity of the compressor. The compressor cost loss function is as follows: ,in, LimY This indicates the cost of the compressor. β This represents the ratio of annual operating and maintenance costs to the total cost of the compressor. W Indicates the compressor capacity. W 0 represents the minimum capacity value of the compressor required to ensure the normal operation of the natural gas network's gas load. C a This indicates the unit capacity cost of the compressor. C b This indicates the compressor's unit capacity loss due to load shedding.

3. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions; when executed by a processor, the computer program instructions implement the system compressor determination method for reducing the effects of voltage sags as described in any one of claims 1 to 2.

4. A compressor-based system for reducing the effects of voltage sags, characterized in that, include: The computer-readable storage medium as described in claim 3.

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