Multi-energy complementary project power supply optimal configuration method

Abstract

The invention belongs to the technical field of wind, light and fire storage multi-energy complementation, and particularly relates to a multi-energy complementation project power supply optimization configuration method. Comprising the following steps: S1, setting a key index system and forming a multi-energy complementary project basic scheme; s2, performing project operation simulation; s3, key index calculation is carried out, and different configuration schemes are formed; s4, determining an optimal configuration scheme; through the steps, the multi-energy complementary project power supply optimal configuration method can realize optimal configuration of coal power, wind power, photovoltaic and energy storage scales on the basis of meeting three constraints of green, reliable and economic, and meets a power transmission curve required by a receiving end province. Meanwhile, the cost per kilowatt-hour of a project can be measured and calculated, and a basis is provided for measuring the electricity price competitiveness of a new energy base and formulating a reasonable on-grid electricity price.

Description

Technical Field

[0001] The present invention belongs to the technical field of complementary multi - energy of wind, light, thermal power and energy storage, and particularly relates to a method for optimizing the power source configuration of a complementary multi - energy project. Background Art

[0002] Actively promoting the construction of complementary multi - energy clean energy bases, the complementary multi - energy of wind, light, thermal power and energy storage is a development model commonly adopted in current large - scale integrated energy bases. The integrated model of wind, light, thermal power and energy storage means that a certain capacity of thermal power and energy storage is configured in a new energy base to jointly smooth the output characteristics of new energy and improve the power supply reliability. Optimizing the power source configuration is an important part of the feasibility study of a complementary multi - energy project, which needs to meet the constraints of greenness, reliability and economy at the same time. In terms of greenness, according to the requirements of the "Guiding Opinions on Promoting the Integration of Power Source, Grid, Load and Energy Storage and Complementary Multi - Energy Development", the proportion of new energy electricity in the sending - end base is not less than 50%; the comprehensive utilization rate of new energy power generation in the sending - end base is controlled at a reasonable level, reaching 90% and above. In terms of reliability, it does not increase the peak - shaving pressure of the receiving - end system, takes into account the load characteristics of the receiving - end and the output characteristics of new energy in the sending - end to form a reasonable power transmission curve, and tries to reduce the power support provided by the sending - end main grid for the sending - end base. In terms of economy, the comprehensive on - grid electricity price of the complementary multi - energy project is lower than the market - based average purchase price of electricity in the receiving - end system, and the utilization hours of coal - fired power generation are about 4000. Therefore, it is necessary to propose a power source optimization configuration method that meets the three types of constraints to provide practical guidance for the planning of complementary multi - energy projects. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for optimizing the power source configuration of a complementary multi - energy project. On the basis of meeting the three types of constraints of greenness, reliability and economy, it realizes the optimal configuration of the scales of coal - fired power, wind power, photovoltaic power and energy storage, meets the power transmission curve required by the receiving - end province, and at the same time can calculate the cost per kilowatt - hour of the project, providing a basis for measuring the electricity price competitiveness of new energy bases and formulating a reasonable on - grid electricity price.

[0004] The purpose of the present invention is achieved as follows: A method for optimizing the power source configuration of a complementary multi - energy project includes the following steps:

[0005] S1. Set up a key index system and form a basic plan for the complementary multi - energy project;

[0006] S2. Conduct project operation simulation;

[0007] S3. Calculate key indexes and form different configuration plans;

[0008] S4. Determine the optimal configuration plan.

[0009] Further, the key index system set in step S1 includes:

[0010] Proportion P of green power transmission n , which is used to measure the proportion of new energy power in the total power transmitted out;

[0011] Utilization rate P of new energy l , which is used to evaluate the utilization of wind power and photovoltaic power under the integrated operation mode;

[0012] Power E supported by the sending-end main grid s , which is the power supported by the sending-end power grid when there is a gap in the power transmission curve under the conditions that the wind and light output of the new energy base is insufficient, the energy storage regulation capacity is exhausted, and the coal-fired power generation reaches its peak;

[0013] Utilization hours H of coal-fired power generation, which is used to evaluate the operation efficiency and economy of coal-fired power;

[0014] Utilization rate P of energy storage c , which is used to evaluate the operation efficiency and economy of energy storage;

[0015] Cost per kilowatt-hour p, which is used to evaluate the project economy from the perspective of cost.

[0016] Furthermore, the formation of the basic multi-energy complementary project plan in step S1 includes:

[0017] According to the demand characteristics of the receiving-end power grid in different seasons, the power transmission curve demand is formed. According to the power transmission curve demand, the initial installed capacities of wind power, photovoltaic power, and coal-fired power of the multi-energy complementary project are initially set to G f 、G g 、G m , and the new energy storage is a 2-hour system, configured according to 20% of the total installed capacity of new energy.

[0018] Furthermore, the project operation simulation in step S2 includes:

[0019] Using the power transmission curve s required by the receiving-end power grid and the new energy output curve G of the multi-energy complementary project, the initial coal-fired power output curve M1 and the new energy primary surplus power curve Q1 are obtained, where the installed capacities of wind power and photovoltaic power are respectively recorded as G f 、G g ;

[0020] S - G = M1 + Q1 (1)

[0021] The installed capacity of coal-fired power is recorded as G m , and a new coal-fired power output curve M2 and a new energy surplus power curve Q2 are formed to ensure that the minimum value of M2 is 30% of the rated power of coal-fired power;

[0022]

[0023] The energy storage capacity is recorded as R C, considering the effective capacity of 85% of the energy storage, the surplus power curve Q2 of new energy is used to charge the energy storage to form a charging curve C;

[0024] C ∈ Q2 (3)

[0025] Considering the charge-discharge loss of 5% of the energy storage, during the periods without wind and light curtailment, the energy storage is used for discharging; during the specific periods of M2 (when the coal power output exceeds the rated power), discharging is given priority. After the energy storage is discharged, the part of the curve M2 that is still higher than the rated power of the coal power is recorded as the curve W s , W s is the power curve that still requires the support of the sending-end main grid, and from this, the support power E of the sending-end main grid is calculated s ;

[0026] Form the energy storage discharge curve F and the final power generation curve M3 of the coal power;

[0027]

[0028] Furthermore, the key index calculation and formation of different configuration schemes in the step S3 include:

[0029] According to the power curve generated by production simulation, key indexes are calculated.

[0030]

[0031] According to production simulation, the transmitted power of coal power, wind power, photovoltaic power and energy storage can be obtained. Considering the costs of various types of power sources, the levelized cost of electricity of the multi-energy complementary project is calculated.

[0032]

[0033] In the formula, B m is the average annual cost of the coal power over its entire life cycle, including fixed costs and variable costs; p w is the average on-grid electricity price of the sending-end power grid; B f , B g , B c are the average annual costs of wind power, photovoltaic power and energy storage over their entire life cycles respectively;

[0034] Based on the basic scheme, with the coal power installed capacity unchanged, according to a certain rule, the installed capacities of wind power and photovoltaic power are gradually increased, and the proportion of the energy storage installed capacity remains 20% to form different configuration schemes.

[0035] Furthermore, the determination of the optimal configuration scheme in the step S4 includes:

[0036] Form a set of feasible schemes; repeat steps S2 and S3 to calculate the key indexes under different configuration schemes. The feasible schemes need to meet the following conditions simultaneously.

[0037]

[0038] Find the optimal solution; among the feasible solution set, E s The smaller the better, P c The solution with the larger the better is selected as the optimal solution.

[0039] Advantages of the present invention: A method for optimizing the power configuration of a multi-energy complementary project of the present invention includes steps S1, setting a key index system and forming a basic plan for the multi-energy complementary project; S2, performing project operation simulation; S3, calculating key indexes and forming different configuration plans; S4, determining the optimal configuration plan; through the above steps, the method for optimizing the power configuration of a multi-energy complementary project of the present invention can, on the basis of meeting the three types of constraints of green, reliable, and economic, realize the optimal configuration of the scales of coal power, wind power, photovoltaic power, and energy storage, and meet the power transmission curve required by the receiving province. At the same time, the cost per kilowatt-hour of the project can be measured, providing a basis for measuring the price competitiveness of new energy bases and formulating reasonable on-grid electricity prices. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 It is a schematic diagram of a DC power transmission curve.

[0042] Figure 2 It is a schematic diagram of the operation curve of a typical multi-energy complementary project on a certain day. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The following will further illustrate the present invention with reference to the drawings.

[0044] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0046] A method for optimizing the power configuration of a multi-energy complementary project of the present invention includes the following steps:

[0047] S1. Set up a key index system and form a basic plan for the multi - energy complementary project;

[0048] S2. Conduct project operation simulation;

[0049] S3. Calculate key indexes and form different configuration plans;

[0050] S4. Determine the optimal configuration plan.

[0051] Furthermore, the key index system set in step S1 includes:

[0052] Green power transmission ratio P n , which is used to measure the proportion of new - energy electricity in the total electricity transmitted out;

[0053] New - energy utilization rate P l , which is used to evaluate the utilization of wind power and photovoltaic power under the integrated operation mode;

[0054] Power supported by the sending - end main grid E s , which is the electricity supported by the sending - end power grid when there is a gap in the power - transmission curve under the conditions that the wind and light output of the new - energy base is insufficient, the energy - storage regulation capacity is exhausted, and the coal - fired power generation reaches its peak;

[0055] Utilization hours of coal - fired power generation H, which is used to evaluate the operation efficiency and economy of coal - fired power generation;

[0056] Energy - storage utilization rate P c , which is used to evaluate the operation efficiency and economy of energy storage;

[0057] Cost per kilowatt - hour p, which is used to evaluate the economy of the project from the perspective of cost.

[0058] Furthermore, the formation of the basic plan for the multi - energy complementary project in step S1 includes:

[0059] According to the demand characteristics of the receiving - end power grid in different seasons, form the power - transmission curve demand. According to the power - transmission curve demand, the initial installed capacities of wind power, photovoltaic power, and coal - fired power of the multi - energy complementary project are initially set as G f 、G g 、G m , and the new - type energy storage is a 2 - hour system, configured according to 20% of the total installed capacity of new energy.

[0060] Furthermore, the project operation simulation in step S2 includes:

[0061] Using the power - transmission curve S required by the receiving - end power grid and the new - energy output curve G of the multi - energy complementary project, obtain the initial coal - fired power output curve M1 and the new - energy primary surplus power curve Q1, where the installed capacities of wind power and photovoltaic power are respectively denoted as G f 、G g ;

[0062] S - G = M1 + Q1 (1)

[0063] The coal - fired power installation is denoted as G m , considering the minimum peaking depth of 30% for coal - fired power, to ensure that the coal - fired power units do not perform start - stop peaking, during a specific period of M1 (when the coal - fired power output is less than 30% of the rated power), the curtailment of new energy in the corresponding period is increased to form a new coal - fired power output curve M2 and a new new - energy surplus power curve Q2, ensuring that the minimum value of M2 is 30% of the coal - fired power rated power;

[0064]

[0065] The energy storage capacity is denoted as R C , considering 85% of the effective capacity of the energy storage, the energy storage is charged using the new - energy surplus power curve Q2 to form a charging curve C;

[0066] C ∈ Q2(3)

[0067] Considering 5% of the charge - discharge loss of the energy storage, during the period without wind and solar curtailment, the energy storage is discharged; during a specific period of M2 (when the coal - fired power output exceeds the rated power), it is preferentially discharged. After the energy storage is discharged, the part of the curve M2 that is still higher than the coal - fired power rated power is denoted as curve W s , W s is the power curve that still requires the support of the sending - end main grid, and the sending - end main grid support power E is calculated therefrom s ;

[0068] The discharge of the energy storage will relieve the pressure of the coal - fired power output. It is still necessary to ensure that the power generation power of the coal - fired power after the energy storage is discharged is higher than 30% of the coal - fired power rated power, forming an energy - storage discharge curve F and the final coal - fired power generation curve M3;

[0069]

[0070] Furthermore, the calculation of key indicators and the formation of different configuration schemes in step S3 include:

[0071] Calculating key indicators based on the power curve generated by production simulation,

[0072]

[0073] According to the production simulation, the power delivered by coal - fired power, wind, light, and energy storage can be obtained. Considering the costs of various types of power sources, the levelized cost of electricity of the multi - energy complementary project is calculated,

[0074]

[0075] In the formula, B m$C_{coal}$ is the average annual cost of the entire life cycle of coal power, including fixed costs and variable costs; among them, the fixed costs are the construction, finance, and operation and maintenance costs of the unit, and the variable cost is the coal consumption cost; $p$ w is the average on-grid electricity price of the sending-end power grid; $B$ f $B$ g $B$ c $C_{wind}$, $C_{solar}$, and $C_{energy storage}$ are the average annual costs of the entire life cycle of wind power, photovoltaic power, and energy storage respectively, mainly including the construction, finance, and operation and maintenance costs of the equipment, and there is no variable cost;

[0076] Based on the basic plan, without changing the installed capacity of coal power, the installed capacities of wind power and photovoltaic power are gradually increased according to a certain rule (such as in a gradient of 1 million kilowatts), and the proportion of energy storage installed capacity remains 20%, forming different configuration plans.

[0077] Furthermore, the determination of the optimal configuration plan in step S4 includes:

[0078] Form a set of feasible plans; repeat steps S2 and S3 to calculate the key indicators under different configuration plans. The feasible plans need to meet the following conditions simultaneously,

[0079]

[0080] Find the optimal plan; in the set of feasible plans, the smaller $E$ s is, and the larger $P$ c is, the better the plan is selected as the optimal plan.

[0081] The present invention will be further described below with a specific case.

[0082] (1) Power transmission curve of the power source base

[0083] Regarding the demand characteristics of the receiving-end power grid in different seasons, considering that the receiving-end power supply guarantee needs are met as much as possible in summer and winter, based on the relatively high power transmission level during the noon peak, relying on the supporting role of coal power and the regulating role of energy storage to improve the power transmission capacity during the evening peak; in spring and autumn, the demand for new energy consumption is considered. Referring to the power transmission curves of the in-service DC channels, the curves are drawn in three steps in summer and winter, and in two steps in spring and autumn. The power transmission capacities at the high steps (9 - 15 hours) in the four seasons are 6.9 million kilowatts, 5.8 million kilowatts, 6.1 million kilowatts, and 6.0 million kilowatts respectively, and the power transmission capacities at the low steps are all 2.85 million kilowatts; the power transmission in the evening peak (17 - 21 hours) in summer is 5.7 million kilowatts, and the power transmission in the evening peak in winter is 5.5 million kilowatts. The specific DC power transmission curve is shown in Figure 1 .

[0084] (2) Basic configuration plan and index measurement results

[0085] Under the basic configuration plan, the proportion of green power transmission is low and the energy storage utilization rate is low, so it is necessary to increase the installed capacity of wind and solar power. The basic configuration plan for the multi-energy complementary project is as follows: the installed capacity of coal-fired power is 4 million kilowatts, the installed capacity of wind power is 4 million kilowatts, the installed capacity of photovoltaic power is 7 million kilowatts, and the energy storage capacity is configured at 20% of the total installed capacity of wind and solar power. Through production simulation calculations, the green power transmission ratio is 40.8%, the new energy utilization rate is 99.3%, the supporting power of the sending-end main grid is 1.02 billion kWh, the utilization hours of coal-fired power generation are 5,217 hours, the energy storage utilization rate is 27.9%, and the cost per kWh is 0.2905 yuan / kWh.

[0086] (3) Results of multi-scheme configuration and index calculation

[0087] As the scale of wind power and photovoltaic power increases, the proportion of green power transmission gradually increases, while the new energy utilization rate and the utilization hours of coal-fired power generation decrease. Based on the basic configuration plan, the installed capacity of wind power and photovoltaic power is gradually increased in gradients of 1 million kilowatts. Production simulation is used to conduct simulations and calculate the key indicators under each plan. The set of feasible plans formed according to the constraint conditions is shown in Table 1.

[0088] Table 1 Technical comparison of power source configuration plans for multi-energy complementary projects Unit: 10,000 kW, hour, 100 million kWh, %

[0089]

[0090] (4) Determine the optimal plan

[0091] The optimal plan meets the basic constraint conditions, with a relatively low supporting power of the sending-end power grid and a relatively high energy storage utilization rate. After comparison and selection, Plan 5 is the optimal plan: the installed capacity of coal-fired power is 4 million kilowatts, the installed capacity of wind power is 5 million kilowatts, the installed capacity of photovoltaic power is 12 million kilowatts, and the configured energy storage is 3.4 million kW / 2 hours. The operation curve of the multi-energy complementary project on a typical day is as Figure 2 shown. Through production simulation calculations, the green power transmission ratio is 54.2%, the new energy utilization rate is 90.4%, the supporting power of the sending-end main grid is 0.39 billion kWh, the utilization hours of coal-fired power generation are 4,101 hours, the energy storage utilization rate is 70.5%, and the cost per kWh is 0.2796 yuan / kWh.

[0092] From an economic perspective, the cost per kWh of new energy and coal-fired power in the optimized plan is higher than that in the basic plan, while the cost per kWh of energy storage is lower than that in the basic plan. As shown in Table 2, the overall cost per kWh of the project is reduced by 0.0109 yuan / kWh compared with the basic plan.

[0093] Table 2 Comparative analysis of the cost per kWh of different plans Unit: 100 million kWh, 100 million yuan, yuan / kWh

[0094]

[0095]

[0096] In summary, a method for optimizing the power configuration of a multi-energy complementary project according to the present invention includes the following steps: Step S1, setting a key index system and forming a basic plan for the multi-energy complementary project; Step S2, conducting project operation simulation; Step S3, calculating key indexes and forming different configuration plans; Step S4, determining the optimal configuration plan. Through the above steps, the method for optimizing the power configuration of a multi-energy complementary project according to the present invention can, on the basis of meeting the three types of constraints of green, reliable, and economic, realize the optimal configuration of the scales of coal power, wind power, photovoltaic power, and energy storage, and meet the power transmission curve required by the receiving province. At the same time, the cost per kilowatt-hour of the project can be calculated, providing a basis for measuring the price competitiveness of new energy bases and formulating reasonable on-grid electricity prices.

[0097] In the description of this specification, the description with reference to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0098] The above has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A method for optimizing the power source configuration of a multi-energy complementary project, characterized in that It includes the following steps: S1. Set up a key index system and form a basic plan for the multi-energy complementary project; S2. Conduct project operation simulation; S3. Calculate key indexes and form different configuration plans; S4. Determine the optimal configuration plan.

2. The power optimization configuration method for a multi-energy complementary project according to claim 1, wherein The key index system set in step S1 includes: Proportion P of green power transmission n , which is used to measure the proportion of new energy power in the total externally transmitted power; New energy utilization rate P l , used to evaluate the utilization of wind power and photovoltaic power under the integrated operation mode; The power quantity E supported by the sending-end main grid s is the power quantity supported by the sending-end grid when there is a gap in the power transmission curve under the conditions that the new energy base has insufficient wind and solar power output, the energy storage regulation capacity is exhausted, and the coal-fired power is at its peak power generation. The utilization hours of coal power generation H, which is used to evaluate the operation efficiency and economy of coal power; Energy storage utilization rate P c , which is used to evaluate the operation efficiency and economy of energy storage; The cost per kilowatt-hour p, which is used to evaluate the economy of the project from the perspective of cost.

3. The method for optimizing the power source configuration of a multi-energy complementary project according to claim 2, wherein, The formation of the basic plan for the multi-energy complementary project in step S1 includes: According to the demand characteristics of the receiving-end power grid in different seasons, the power transmission curve demand is formed. According to the power transmission curve demand, the installed capacities of wind power, photovoltaic power, and coal power in the multi-energy complementary project are initially set to G f 、G g 、G m 。 4. The method for optimizing the power supply configuration of a multi-energy complementary project according to claim 1, characterized in that The project operation simulation in step S2 includes: Using the power transmission curve S required by the receiving-end power grid and the new energy output curve G of the multi-energy complementary project, the preliminary coal power output curve M1 and the new energy primary surplus power curve Q1 are obtained, where the installed capacities of wind power and photovoltaic are denoted as G f 、G g ; S - G = M1 + q1 (1) The coal-fired power installed capacity is denoted as G m , to form a new coal-fired power output curve M2 and a new new energy surplus power curve Q2, and ensure that the minimum value of M2 is 30% of the rated power of the coal-fired power The energy storage capacity is denoted as R C , considering 85% of the effective capacity of the energy storage, the surplus power curve Q2 of the new energy is used to charge the energy storage to form a charging curve C; Considering the 5% charge and discharge losses of energy storage, during the periods without curtailment of wind and solar power, the energy storage is used for discharging; after the energy storage finishes discharging, the part of curve M2 that is still higher than the rated power of coal-fired power is denoted as curve W s , W s is the power curve that still requires the support of the sending-end main grid, and the support electricity quantity E of the sending-end main grid is calculated therefrom s ; Form the energy storage discharge curve F and the final power generation curve M3 of coal power; 5. The method for optimizing the power supply configuration of a multi-energy complementary project according to claim 1, wherein The calculation of key indexes and the formation of different configuration plans in step S3 include: Calculate the key indexes according to the power curve generated by production simulation, According to the power transmission amounts of coal power, wind power, photovoltaic power and energy storage obtained from production simulation, and considering the costs of various types of power sources, calculate the cost per kilowatt-hour of the multi-energy complementary project, Where, B m is the average annual cost of the entire life cycle of coal power, including fixed costs and variable costs; p w is the average on-grid electricity price of the sending-end power grid; B f , B g , B c are the average annual costs of the entire life cycles of wind power, photovoltaic power, and energy storage respectively; Based on the basic plan, without changing the installed capacity of coal power, gradually increase the installed capacities of wind power and photovoltaic power according to a certain rule, and keep the proportion of energy storage installed capacity at 20%, so as to form different configuration plans.

6. The method for optimizing the power source configuration of a multi-energy complementary project according to claim 1, wherein The determination of the optimal configuration plan in step S4 includes: Form a set of feasible plans; repeat steps S2 and S3, calculate the key indexes under different configuration plans, and the feasible plans need to meet the following conditions at the same time, Find the optimal solution; among the feasible solution set, the smaller E s the better, and the larger P c the better, the solution is selected as the optimal solution.

Images