A method for constructing a new energy consumption restriction scenario and calculating pumped storage demand

Abstract

The present invention discloses a method for constructing a new energy consumption restriction scenario and calculating pumped storage demand, including introducing multiple new energy restriction factors from power balance demand, peak load demand, and unit operation characteristics to construct a new energy consumption restriction scenario; for the new energy consumption restriction scenario, a bottleneck analysis model is constructed to identify areas where the line transmission capacity in the grid does not meet the preset transmission capacity requirements and the new energy consumption level does not meet the preset consumption level; based on different new energy consumption restriction scenarios, with the goal of eliminating grid bottlenecks, pumped storage demand analysis is performed to obtain pumped storage capacity that meets the requirements of new energy consumption and safe and stable operation of the power grid. This provides technical support and theoretical basis for further improving the pumped storage demand calculation method and rationally arranging pumped storage in the future considering the grid structure of the power grid.

Description

Technical Field

[0001] The present invention belongs to the field of power systems, and in particular relates to a method for constructing a new energy consumption restriction scenario and calculating pumped storage demand. Background Art

[0002] In the future, new energy represented by wind power and photovoltaic power will gradually replace traditional fossil energy and become the main power supply. In order to support the safe and stable operation of a high proportion of new energy power grid, large-scale regulating power sources need to be developed on a large scale. However, due to the randomness and volatility of new energy development and the limited carrying capacity of the power grid, its large-scale development will bring huge difficulties to the consumption of new energy and the safe and stable operation of the power grid. Therefore, pumped storage, as a flexible power source that can both store electricity and convert energy, can participate in the power and peak-shaving balance of the new power system.

[0003] Existing research mainly studies hybrid systems containing multiple energy sources such as pumped storage, renewable energy, and thermal power from the three perspectives of economy, reliability, and new energy consumption. It does not take into account the source-load mismatch caused by differences in resource distribution in actual regions and the inability of inter-regional transmission channels to meet requirements.

[0004] Therefore, it is of great significance to study the construction of new energy consumption restriction scenarios based on bottleneck analysis and the calculation method of pumped storage demand. Summary of the invention

[0005] In response to the above technical problems, the present invention provides a method for constructing a new energy consumption restriction scenario and calculating pumped storage demand.

[0006] The technical solution adopted by the present invention to solve the technical problem is:

[0007] A method for constructing a new energy consumption restriction scenario and calculating pumped storage demand, the method comprising the following steps:

[0008] Step S100: Based on power balance demand, peak load demand, and unit operation characteristics, multiple new energy restriction factors are introduced to construct a new energy consumption restriction scenario;

[0009] Step S200: for the scenario of new energy consumption restriction, a bottleneck analysis model is constructed to identify areas in the grid where the line transmission capacity does not meet the preset transmission capacity requirements and the new energy consumption level does not meet the preset consumption level;

[0010] Step S300: Based on different scenarios of new energy consumption restriction, with the goal of eliminating grid bottlenecks, a pumped storage demand analysis is performed to obtain a pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid.

[0011] Preferably, step S100 includes:

[0012] Step S110: Establish multiple restriction indicators that affect the consumption of new energy and the safe and stable operation of the power grid from the aspects of power balance demand, peak load demand, and unit operation characteristics;

[0013] Step S120: Construct a new energy consumption restriction scenario based on restriction indicators that affect new energy consumption and safe and stable operation of the power grid.

[0014] Preferably, step S110 includes:

[0015] (1) Power balance relationship constraints:

[0016]

[0017] Where N g Indicates the number of thermal power units, N r Represents the amount of new energy, N l Indicates the number of out-of-area calls, N hh Indicates the number of hydropower units, N h represents the number of pumped storage power stations, N d represents the number of partition loads, P g,t Represents the output of thermal power units, P r,t Represents the output of new energy, P l,t represents the external power of the lth area, α represents the proportion of pumped storage power stations participating in peak load regulation, P hh,t Indicates the output of the hydropower unit, P h,max Indicates the maximum output of the pumped storage power station, P d,t represents the load demand of partition d;

[0018] (2) Peak load balancing demand constraints:

[0019] Determine the maximum output of the required thermal power unit based on the typical daily maximum load:

[0020]

[0021] Determine the peak load demand based on the minimum load on a typical day:

[0022]

[0023] Where P dmax,t , P dmin,t Respectively represent the maximum and minimum values ​​of the partition load; δ g , ε hh ,ω r , π l They represent the peak load coefficients of thermal power units, hydropower units, new energy units, and external power, ΔP h Indicates that the peak load demand of the power grid is met by pumped storage power stations;

[0024] (3) Unit operating characteristics:

[0025] 1) Operation constraints of thermal power units:

[0026] Output constraint: P g,min ≤P g,t ≤P g,max

[0027] Run climbing constraint: -R D Δt≤P g,t -P g,t-1 ≤R U ·Δt

[0028] Where P g,min , P g,max Respectively represent the minimum and maximum output of thermal power units; P g,t-1 represents the power of the g-th unit at time t-1, R D , R U It indicates the power climbing up and down coefficients, and Δt indicates the time interval;

[0029] 2) Operation constraints of pumped storage power stations:

[0030] Pumping constraint: 0≤P h,t ≤β h P hs,max

[0031] Release constraint: 0≤P h,t ≤η h P hs,max

[0032] And β h +η h ≤1;

[0033] Where P hs,max represents the installed capacity of the hydropower unit, β h , η h They respectively represent the discharge status and pumping status of the pumped-storage power station, and the two cannot be 1 at the same time.

[0034] Preferably, step S120 includes:

[0035]

[0036] In the formula, represents the scenario considering only the power demand; Indicates the scenario where only peak load demand is considered; Indicates the scenario that only considers the unit operation characteristics; It indicates the scenario that comprehensively considers power demand, peak load demand and unit operation characteristics.

[0037] Preferably, step S200 includes:

[0038] Step S210: Introduce the concept of bottleneck of urban rail transit network, and divide the grid operation bottleneck of the new energy consumption restriction scenario in the power system into static bottleneck and dynamic bottleneck; wherein, the static bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and without adding new energy; the dynamic bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and adding new energy, and the area where the line transmission capacity in the grid is limited when considering the "N-1" fault and "N-2" fault of the grid and adding new energy;

[0039] Step S220: converting the static bottleneck of the line into a dynamic bottleneck and establishing a bottleneck analysis model for it;

[0040] Step S230: Taking the renewable energy capacity that can be carried by the zoned power grid as the research object, based on the bottleneck analysis model, identify areas where the line transmission capacity does not meet the preset transmission capacity requirements and the renewable energy consumption level does not meet the preset consumption level.

[0041] Preferably, the bottleneck analysis model in step S220 is specifically:

[0042]

[0043] In the formula, QA k (t) represents the set of dynamic bottleneck intervals in line k at time t; QA k,j (t) indicates that interval j in line k at time t becomes the line bottleneck set; It represents the cross-sectional transport flow of section j in line k at time t; represents the maximum transmission capacity of section j in line k at time t; Z q represents the bottleneck critical value of the section line; J k represents the set of lines k.

[0044] Preferably, step S230 is specifically:

[0045] The direction of the transmission flow of the section line determines the level of new energy consumption; the size of the transmission flow of the section line determines the line transmission capacity.

[0046] Preferably, step S300 is specifically:

[0047] Step S310: determining the output of new energy at time t and the total power generated by new energy at time t according to the new energy consumption restriction scenarios under different constraints;

[0048] Step S320: obtaining a new energy consumption rate corresponding to a new energy consumption restriction scenario according to the new energy output at time t and the total new energy output power at time t;

[0049] Step S330: Based on the new energy consumption rate under each new energy consumption restriction scenario, the pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid under each scenario is obtained.

[0050] Preferably, step S320 is specifically:

[0051]

[0052] Where P r,t represents the output of new energy at time t, P rz,t represents the total power generated by renewable energy at time t, and X represents the renewable energy consumption rate.

[0053] The above-mentioned construction of new energy consumption restriction scenarios and calculation method of pumped storage demand provide technical support and theoretical basis for further improving the calculation method of pumped storage demand and rationally planning pumped storage in the future considering the grid structure of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a flow chart of a method for constructing a new energy consumption restriction scenario and calculating pumped storage demand of the present invention;

[0055] Figure 2 It is a schematic diagram of a power system grid structure in which the present invention is specifically applied in an embodiment;

[0056] Figure 3 The annual new energy development scale of a certain province in which the present invention is specifically applied in the embodiment;

[0057] Figure 4 The present invention is specifically applied in the embodiment to identify lines with insufficient transmission capacity and areas with low new energy consumption level based on the bottleneck model. DETAILED DESCRIPTION

[0058] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0059] In one embodiment, Figure 1 As shown, a method for constructing a new energy consumption restriction scenario and calculating pumped storage demand includes the following steps:

[0060] Step S100: Based on power balance demand, peak load demand, and unit operation characteristics, multiple new energy restriction factors are introduced to construct a new energy consumption restriction scenario;

[0061] Step S200: for the scenario of new energy consumption restriction, a bottleneck analysis model is constructed to identify areas in the grid where the line transmission capacity does not meet the preset transmission capacity requirements and the new energy consumption level does not meet the preset consumption level;

[0062] Step S300: Based on different scenarios of new energy consumption restriction, with the goal of eliminating grid bottlenecks, a pumped storage demand analysis is performed to obtain a pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid.

[0063] The above-mentioned construction of new energy consumption restriction scenarios and calculation method of pumped storage demand provide technical support and theoretical basis for further improving the calculation method of pumped storage demand and rationally planning pumped storage in the future considering the grid structure of the power grid.

[0064] In one embodiment, step S100 includes:

[0065] Step S110: Establish multiple restriction indicators that affect the consumption of new energy and the safe and stable operation of the power grid from the aspects of power balance demand, peak load demand, and unit operation characteristics;

[0066] Step S120: Construct a new energy consumption restriction scenario based on restriction indicators that affect new energy consumption and safe and stable operation of the power grid.

[0067] Specifically, the consumption of new energy is constrained by resources and the grid structure. The amount of new energy consumed under a single constraint or multiple constraints is different, which constitutes different scenarios, namely multiple new energy consumption restriction scenarios.

[0068] In one embodiment, step S110 includes:

[0069] (1) Power balance relationship constraints:

[0070]

[0071] Where N g Indicates the number of thermal power units, N r Represents the amount of new energy, N l Indicates the number of out-of-area calls, N hh Indicates the number of hydropower units, N h represents the number of pumped storage power stations, N d represents the number of partition loads, P g,t Represents the output of thermal power units, P r,t Represents the output of new energy, P l,t represents the external power of the lth area, α represents the proportion of pumped storage power stations participating in peak load regulation, P hh,t Indicates the output of the hydropower unit, P h,max Indicates the maximum output of the pumped storage power station, Pd,t represents the load demand of partition d;

[0072] (2) Peak load balancing demand constraints:

[0073] Determine the maximum output of the required thermal power unit based on the typical daily maximum load:

[0074]

[0075] Determine the peak load demand based on the minimum load on a typical day:

[0076]

[0077] Where P dmax,t , P dmin,t Respectively represent the maximum and minimum values ​​of the partition load; δ g , ε hh ,ω r , π l They represent the peak load coefficients of thermal power units, hydropower units, new energy units, and external power, ΔP h Indicates that the peak load demand of the power grid is met by pumped storage power stations;

[0078] (3) Unit operating characteristics:

[0079] 1) Operation constraints of thermal power units:

[0080] Output constraint: P g,min ≤P g,t ≤P g,max

[0081] Run climbing constraint: -R D Δt≤P g,t -P g,t-1 ≤R U ·Δt

[0082] Where P g,min , P g,max Respectively represent the minimum and maximum output of thermal power units; P g,t-1 represents the power of the g-th unit at time t-1, R D , R U It indicates the power climbing up and down coefficients, and Δt indicates the time interval;

[0083] 2) Operation constraints of pumped storage power stations:

[0084] Pumping constraint: 0≤P h,t ≤β h P hs,max

[0085] Release constraint: 0≤P h,t ≤ηh P hs,max

[0086] And β h +η h ≤1;

[0087] Where P hs,max represents the installed capacity of the hydropower unit, β h , η h They respectively represent the discharge status and pumping status of the pumped-storage power station, and the two cannot be 1 at the same time.

[0088] In one embodiment, step S120 includes:

[0089]

[0090] In the formula, represents the scenario considering only the power demand; Indicates the scenario where only peak load demand is considered; Indicates the scenario that only considers the unit operation characteristics; It indicates the scenario that comprehensively considers power demand, peak load demand and unit operation characteristics.

[0091] In one embodiment, step S200 includes:

[0092] Step S210: Introduce the concept of urban rail transit network bottleneck, and divide the grid operation bottleneck of the new energy consumption restriction scenario in the power system into static bottleneck and dynamic bottleneck; wherein, the static bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and without adding new energy; the dynamic bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and adding new energy, and the area where the line transmission capacity in the grid is limited when considering the "N-1" fault and "N-2" fault of the grid and adding new energy.

[0093] Specifically, the dynamic bottleneck mainly considers the level of new energy consumption and the transient stability of the power grid. Figure 2 As shown in the figure, A, B, C, and D in the grid represent that the entire power grid of a certain region is divided into four sub-grids. In 11, 12…1j, 21, 22…2j, and 31, 32…3j, the first digit represents the kth transmission channel between sub-grids A and B, C, and D, and the second digit represents the jth line in the kth transmission channel.

[0094] Step S220: convert the static bottleneck of the line into a dynamic bottleneck and establish a bottleneck analysis model for it.

[0095] Specifically, according to the above analysis, the static bottleneck of power grid operation is mainly reflected in the transmission capacity of the interval line. However, when new energy is added, the current carrying capacity demand of the interval line will increase or the line full / overload rate will increase, so the static bottleneck of the line will turn into a dynamic bottleneck, and a bottleneck analysis model will be established for it.

[0096] In one embodiment, the bottleneck analysis model in step S220 is specifically:

[0097]

[0098] In the formula, QA k (t) represents the set of dynamic bottleneck intervals in line k at time t; QA k,j (t) indicates that interval j in line k at time t becomes the line bottleneck set; It represents the cross-sectional transport flow of section j in line k at time t; represents the maximum transmission capacity of section j in line k at time t; Z q represents the bottleneck critical value of the section line; J k represents the set of lines k.

[0099] Specifically, the bottleneck analysis model is based on the transmission capacity of the lines in the network to identify areas where the line transmission capacity does not meet the preset transmission capacity requirements and the new energy consumption level does not meet the preset consumption level. This process requires modeling calculations and the use of professional software BPA for flow simulation and analysis.

[0100] Step S230: Taking the renewable energy capacity that can be carried by the zoned power grid as the research object, based on the bottleneck analysis model, identify areas where the line transmission capacity does not meet the preset transmission capacity requirements and the renewable energy consumption level does not meet the preset consumption level.

[0101] In one embodiment, step S230 is specifically as follows:

[0102] The direction of the transmission flow of the section line determines the level of new energy consumption; the size of the transmission flow of the section line determines the line transmission capacity.

[0103] Specifically, the direction of the transmission flow of the interval line determines the level of new energy consumption. Generally speaking, if the flow on the connecting line between a certain area P and another area Q generally flows from P to Q, it means that the P area cannot meet the local consumption of new energy and must be sent to Q through the interval connecting line. The new energy consumption level is poor. The transmission capacity of the line is determined by the size of the transmission flow of the interval line. If the transmission flow of a certain line is greater than or equal to 0.8 times the line's maximum transmission capacity, the transmission capacity of the line is judged to be insufficient.

[0104] In one embodiment, step S300 is specifically as follows:

[0105] Step S310: determining the output of new energy at time t and the total power generated by new energy at time t according to the new energy consumption restriction scenarios under different constraints;

[0106] Step S320: obtaining a new energy consumption rate corresponding to a new energy consumption restriction scenario according to the new energy output at time t and the total new energy output power at time t;

[0107] Step S330: Based on the new energy consumption rate under each new energy consumption restriction scenario, the pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid under each scenario is obtained.

[0108] In one embodiment, step S320 is specifically as follows:

[0109]

[0110] Where P r,t represents the output of new energy at time t, P rz,t represents the total power generated by renewable energy at time t, and X represents the renewable energy consumption rate.

[0111] Specifically, the output of new energy at time t refers to the participation in the balance of electric power. The total power output of new energy at time t includes the output of new energy and the power of abandoned new energy. After obtaining the areas with insufficient line transmission capacity and low level of new energy consumption, the required pumped storage capacity is obtained in the selected areas with the goal of maximizing new energy consumption.

[0112] In order to verify the effectiveness of the proposed method for constructing a new energy consumption restriction scenario based on bottleneck analysis and calculating pumped storage demand, the following takes a regional power grid as an example, and the specific data are analyzed as follows:

[0113] The scale of new energy development in a province is as follows Figure 3 shown.

[0114] By calculating the basic grid, we can know that after considering the large-scale access of new energy to the power grid, the power flow in a certain province is as follows: Figure 4 As shown in the figure, the areas where the transmission capacity of the lines in the grid is limited are mainly the transmission channels from the southern Hunan power grid to the eastern Hunan power grid and from the northwestern Hunan power grid to the eastern Hunan power grid.

[0115] According to the new energy scale in the planned year, all lines in the transmission channel of Southern Hunan Power Grid ~ Eastern Hunan Power Grid and Northwest Hunan Power Grid ~ Eastern Hunan Power Grid were checked for "N-1" faults and "N-2" faults, and the transmission lines in the grid bottleneck were found to be the 500kV lines of Yiyang East ~ Shaping, Guting ~ Xingcheng, and Guting ~ Yancheng.

[0116] Analysis of the scale of pumped storage that needs to be increased to increase the level of new energy consumption and eliminate grid bottlenecks:

[0117]

[0118] Calculations show that if the scale of new energy consumption is 1.7 million kilowatts, an additional 600,000 kilowatts of pumped storage capacity will be needed.

[0119] The above is a detailed introduction to the construction of a new energy consumption restriction scenario and a method for calculating pumped storage demand provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for constructing a new energy consumption restriction scenario and calculating pumped storage demand, characterized in that: The method comprises the following steps: Step S100: Based on power balance demand, peak load demand, and unit operation characteristics, multiple new energy restriction factors are introduced to construct a new energy consumption restriction scenario; Step S200: for the new energy consumption restriction scenario, a bottleneck analysis model is constructed to identify areas in the grid where the line transmission capacity does not meet the preset transmission capacity requirements and the new energy consumption level does not meet the preset consumption level; Step S300: Based on different scenarios of new energy consumption restrictions, with the goal of eliminating grid bottlenecks, a pumped storage demand analysis is performed to obtain a pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid; Step S100 includes: Step S110: Establish multiple restriction indicators that affect the consumption of new energy and the safe and stable operation of the power grid from the aspects of power balance demand, peak load demand, and unit operation characteristics; Step S120: constructing a new energy consumption restriction scenario based on restriction indicators that affect new energy consumption and safe and stable operation of the power grid; Step S110 includes: (1) Power balance relationship constraints: Where N g Indicates the number of thermal power units, N r Represents the amount of new energy, N l Indicates the number of out-of-area calls, N hh Indicates the number of hydropower units, N h represents the number of pumped storage power stations, N d represents the number of partition loads, P g,t Represents the output of thermal power units, P r,t Represents the output of new energy, P l,t represents the external power of the lth area, α represents the proportion of pumped storage power stations participating in peak load regulation, P hh,t Indicates the output of the hydropower unit, P h,max Indicates the maximum output of the pumped storage power station, P d,t represents the load demand of partition d; (2) Peak load balancing demand constraints: Determine the maximum output of the required thermal power unit based on the typical daily maximum load: Determine the peak load demand based on the minimum load on a typical day: Where P dmax,t , P dmin,t Respectively represent the maximum and minimum values ​​of the partition load; δ g , ε hh ,ω r , π l They represent the peak load coefficients of thermal power units, hydropower units, new energy units, and external power, ΔP h It means that the peak load demand of the power grid is met by pumped storage power stations; (3) Unit operating characteristics: 1) Operation constraints of thermal power units: Output constraint: P g,min ≤P g,t ≤P g,max Run climbing constraint: -R D Δt≤P g,t -P g,t-1 ≤R U ·Δt Where P g,min , P g,max Respectively represent the minimum and maximum output of thermal power units; P g,t-1 represents the power of the g-th unit at time t-1, R D , R U It indicates the power climbing up and down coefficients, and Δt indicates the time interval; 2) Operation constraints of pumped storage power stations: Pumping constraint: 0≤P h,t ≤β h P hs,max Release constraint: 0≤P h,t ≤η h P hs,max And b h +n h ≤1; Where P hs,max represents the installed capacity of the hydropower generating unit, β h , η h They represent the discharge state and pumping state of the pumped storage power station respectively, and the two cannot be 1 at the same time; Step S200 includes: Step S210: Introduce the concept of bottleneck of urban rail transit network, and divide the grid operation bottleneck of the new energy consumption restriction scenario in the power system into static bottleneck and dynamic bottleneck; wherein the static bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and without adding new energy; the dynamic bottleneck refers to the area where the line transmission capacity in the grid is limited without considering the "N-1" fault and "N-2" fault of the grid and adding new energy, and the area where the line transmission capacity in the grid is limited when considering the "N-1" fault and "N-2" fault of the grid and adding new energy; Step S220: converting the static bottleneck of the line into a dynamic bottleneck and establishing a bottleneck analysis model for it; Step S230: Taking the renewable energy capacity that can be carried by the zoned power grid as the research object, based on the bottleneck analysis model, identify areas where the line transmission capacity does not meet the preset transmission capacity requirements and the renewable energy consumption level does not meet the preset consumption level.

2. The method according to claim 1, characterized in that Step S120 includes: In the formula, represents the scenario considering only the power demand; Indicates the scenario where only peak load demand is considered; Indicates the scenario that only considers the unit operation characteristics; It indicates the scenario that comprehensively considers power demand, peak load demand and unit operation characteristics.

3. The method according to claim 2, characterized in that The bottleneck analysis model in step S220 is specifically: In the formula, QA k (t) represents the set of dynamic bottleneck intervals in line k at time t; QA k,j (t) indicates that interval j in line k at time t becomes the line bottleneck set; It represents the cross-sectional transport flow of section j in line k at time t; represents the maximum transmission capacity of section j in line k at time t; Z q represents the bottleneck critical value of the section line; J k represents the set of lines k.

4. The method according to claim 3, characterized in that Step S230 is specifically as follows: The direction of the transmission flow of the section line determines the level of new energy consumption; the size of the transmission flow of the section line determines the line transmission capacity.

5. The method according to claim 4, characterized in that Step S300 is specifically as follows: Step S310: determining the output of new energy at time t and the total power generated by new energy at time t according to the new energy consumption restriction scenarios under different constraints; Step S320: obtaining a new energy consumption rate corresponding to a new energy consumption restriction scenario according to the new energy output at time t and the total new energy output power at time t; Step S330: Based on the new energy consumption rate under each new energy consumption restriction scenario, the pumped storage capacity that meets the needs of new energy consumption and safe and stable operation of the power grid under each scenario is obtained.

6. The method according to claim 5, characterized in that Step S320 is specifically as follows: Where P r,t represents the output of new energy at time t, P rz,t represents the total power generated by renewable energy at time t, and X represents the renewable energy consumption rate.

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