Micro-grid scheduling optimization method containing Carnot cell and stepped carbon transaction mechanism

Abstract

The invention provides a scheduling optimization method for a micro-grid containing a Carnot cell and a stepped carbon transaction mechanism, and relates to the technical field of micro-grid systems, comprising the following steps: building a micro-grid system containing a Carnot cell and a stepped carbon transaction mechanism, and establishing an equipment model in the system; establishing a daily operation cost model of the micro-grid system containing the Carnot cell and the stepped carbon transaction mechanism; establishing constraint conditions of the micro-grid system containing the Carnot cell and the stepped carbon transaction mechanism; based on the above steps, establishing a mathematical model for scheduling optimization of the microgrid system containing the Carnot cell and the stepped carbon transaction mechanism, and obtaining basic parameters; according to the method, the operation model of equipment such as the Carnot battery is established, the Carnot battery can realize electric heating mutual conversion, the electric heating load of a user and the operation cost are flexibly met, a stepped carbon transaction mechanism is considered, and a microgrid scheduling operation strategy is planned by taking the single-day operation cost as a target, so that the operation cost of the system is reduced, and economic and low-carbon operation of the system is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of microgrid systems, and particularly to a microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism. Background Art

[0002] With the increasingly severe energy crisis and environmental problems, the traditional energy structure dominated by fossil fuels is difficult to meet the needs of sustainable development of modern society. In recent years, governments of various countries have accelerated the development and utilization of renewable energy to achieve the goals of energy conservation, emission reduction and green growth. Renewable energy such as photovoltaic and wind power is favored due to its cleanliness and renewability, but its power generation volatility often leads to difficulties in power grid peak shaving and energy waste problems.

[0003] Energy storage technology is the key means to solve these problems. At present, pumped-storage and electrochemical energy storage are widely used, but they all have their own limitations. Therefore, it is necessary to develop new energy conversion technologies, especially efficient conversion before electrothermal conversion, and combine multiple energy storage methods to achieve low-carbon environmental protection. Therefore, the present invention proposes a microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism to solve the problems existing in the prior art. Summary of the Invention

[0004] In view of the above problems, the present invention proposes a microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism. The microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism realizes flexible conversion between electricity and heat through a Carnot battery, considers the stepped carbon trading mechanism in the operating cost, and plans the microgrid scheduling operation strategy with the single-day operating cost as the goal, thereby reducing the system operating cost.

[0005] To achieve the object of the present invention, the present invention is realized through the following technical solutions: A microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism, comprising the following steps:

[0006] S1: Build a microgrid system including a Carnot battery and a stepped carbon trading mechanism, and establish equipment models in the system;

[0007] S2: Establish a daily operating cost model of the microgrid system including a Carnot battery and a stepped carbon trading mechanism;

[0008] S3: Establish constraint conditions of the microgrid system including a Carnot battery and a stepped carbon trading mechanism;

[0009] S4: Based on the above steps, establish a mathematical model for scheduling optimization of the microgrid system including a Carnot battery and a stepped carbon trading mechanism, and obtain basic parameters;

[0010] S5: Construct the operation of the microgrid system and the output strategies of each part;

[0011] S6: Based on the above steps, establish a mathematical model of the mixed-integer linear programming problem, and use the CPLEX solver and YALMIP toolbox in Matlab to solve it to obtain the scheduling and operation conditions of each device;

[0012] S7: Solve the model and obtain the scheduling optimization results of the microgrid system, and output the daily operating cost of the microgrid system.

[0013] The further improvement lies in that: in the above S1, the microgrid system includes two renewable energy sources, namely photovoltaic and wind power, a combined heat and power unit, a gas boiler, a Carnot battery, and a heat storage device, and the device models include a wind power generation model, a photovoltaic power generation model, a combined heat and power unit model, a gas boiler model, a Carnot battery model, and a heat storage device model.

[0014] The further improvement lies in that: the wind power generation model is:

[0015]

[0016] where v t is the instantaneous wind speed, v in , v r and v out are the cut-in wind speed, rated wind speed, and cut-out wind speed respectively, P r is the rated power of the fan, and P DG is the output power of the fan;

[0017] The photovoltaic power generation model is:

[0018]

[0019] where P SP is the output power of the photovoltaic panel, S is the total area of the photovoltaic panel, is the photovoltaic conversion efficiency, and I is the solar irradiance.

[0020] The further improvement lies in that: the combined heat and power unit model is:

[0021]

[0022] where P CHP,e , P CHP,h are the electric energy and heat energy output by the combined heat and power unit; P GT,e , P GT,h are the electric energy and heat energy output by the gas turbine; P ORC,e is the electric energy output by the low-temperature waste heat power generation device; , [[ID=6�3]]are the heat conversion efficiency of the waste heat boiler and the power generation efficiency of the low-temperature waste heat power generation device respectively; , They are the efficiencies of converting the input natural gas power of the gas turbine into the output electric energy and heat energy respectively; and They are the proportions of the waste heat generated by the gas turbine allocated to the waste heat boiler and the low-temperature waste heat power generation device respectively, and the sum of the two is constantly 1; is the natural gas input to the cogeneration unit; V g is the calorific value of natural gas, 9.88 kWh / m 3 ;

[0023] The gas boiler model is:

[0024]

[0025] Among them, P GB,h is the heat energy output by the gas boiler; is the natural gas input to the gas boiler; is the conversion efficiency of the gas boiler; V g is the calorific value of natural gas, 9.88 kWh / m 3 .

[0026] The further improvement lies in that the Carnot battery model is:

[0027]

[0028] Among them, S CB is the equivalent storage capacity of the Carnot battery; and and are the charging efficiency, discharging efficiency and heat supply efficiency of the Carnot battery respectively; and and are the charging amount, discharging amount and heat release amount of the Carnot battery respectively;

[0029] The heat storage device model is:

[0030]

[0031] Among them, S i is the capacity of the heat storage device, and are the heat charging power and heat discharging power of the heat storage device respectively; and are the heat charging efficiency and heat discharging efficiency of the heat storage device respectively.

[0032] The further improvement lies in that in the S2, the daily operation cost model of the microgrid system is:

[0033]

[0034] Among them, is the gas purchase cost, is the operation and maintenance cost, carbon trading cost, grid interaction cost; is the total system operation cost;

[0035] The gas purchase cost The model is:

[0036]

[0037] Among them, is the natural gas purchase volume in the time period; is the natural gas price in the time period;

[0038] The operation and maintenance cost The model is:

[0039]

[0040] Among them, is the operation and maintenance cost coefficient of the i-th device in the system; is the operating power of the i-th device in the system during the period;

[0041] The carbon trading cost Adopts a stepped carbon trading model, which consists of three parts: a carbon emission quota model, an actual carbon emission model, and a stepped carbon emission trading model;

[0042] Carbon emission quota model:

[0043]

[0044] Actual carbon emission model:

[0045]

[0046] Stepped carbon emission trading model:

[0047]

[0048] Among them, is the total amount of carbon emission rights trading; is the actual carbon emission; is the carbon emission quota;

[0049]

[0050] The grid interaction cost model is:

[0051]

[0052] Among them, and are respectively the electricity purchase volume and the electricity sales volume of the system within a time period; and are respectively the electricity purchase price and the on-grid electricity price.

[0053] A further improvement lies in that: in the step S3, the constraint conditions specifically include:

[0054] The operation of the microgrid system needs to satisfy the upper and lower limit constraints of each device:

[0055]

[0056] Power balance constraint:

[0057]

[0058] Heat balance constraint:

[0059]

[0060] Natural gas balance constraint

[0061] .

[0062] A further improvement lies in that: in the step S4, a mathematical model for the scheduling optimization of the microgrid system with a Carnot battery and a stepped carbon trading mechanism is established based on the system model, objective function, and constraint conditions proposed in S1 - S3, and the initial electrical and thermal load data of the microgrid are obtained; the wind power, photovoltaic data, time-of-use electricity price, and gas price data of a typical day are obtained; and the basic parameters such as the operation efficiency, rated power, and start-stop time of the equipment are obtained.

[0063] A further improvement lies in that: in the step S5, the strategy is as follows: First, the output of photovoltaic and wind power is used to consume renewable energy as much as possible; secondly, the output of each device is allocated according to the electrical and thermal load conditions of the microgrid system; when the power generation is excessive, the excess electric energy is stored in the Carnot battery; when the power generation is insufficient, the electric energy is released; when the demand still cannot be met, electricity is purchased from the external power grid.

[0064] The beneficial effects of the present invention are as follows:

[0065] 1. The present invention constructs an operation model for devices such as a Carnot battery. The Carnot battery can realize the mutual conversion of electricity and heat, flexibly meet the electrical and thermal loads of users, and consider the stepped carbon trading mechanism in the operation cost. With the single-day operation cost as the goal, the microgrid scheduling operation strategy is planned, thereby reducing the system operation cost and realizing the economic and low-carbon operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 is a flowchart of the present invention;

[0067] Figure 2 This is the structural block diagram of the microgrid system of the present invention. Detailed implementation manners

[0068] To deepen the understanding of the present invention, the following will further elaborate on the present invention in combination with embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0069] Embodiment 1

[0070] According to Figure 1 、 2 As shown, this embodiment proposes a microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism, which includes parameter initialization, input data, optimization solution, and output data. The input data includes electricity price and gas price, user load, wind power and photovoltaic output, economic parameters, and equipment efficiency. The optimization solution is to solve the optimal scheduling mathematical model of the microgrid system using the CPLEX solver and YALMIP toolbox in Matlab. The output data includes the optimal scheduling result and the optimal result of the objective function.

[0071] The established low-carbon economic scheduling model with the minimum total operating cost of the microgrid system including a Carnot battery and a stepped carbon trading mechanism:

[0072] The operating cost model of the microgrid system is:

[0073]

[0074] Among them, is the gas purchase cost, is the operation and maintenance cost, is the carbon trading cost, is the grid interaction cost; is the total operating cost of the system.

[0075] The gas purchase cost model is:

[0076]

[0077] Among them, is the natural gas purchase volume in the is the natural gas price in the

[0078] The operation and maintenance cost model is:

[0079]

[0080] Among them, is the operation and maintenance cost coefficient of the i-th device in the system; is the operating power of the i-th device in the system within a cycle.

[0081] Carbon trading cost Adopt a stepped carbon trading model, which consists of three parts: a carbon emission quota model, an actual carbon emission model, and a stepped carbon emission trading model.

[0082] Carbon emission quota model:

[0083]

[0084] Actual carbon emission model:

[0085]

[0086] Stepped carbon emission trading model:

[0087]

[0088] Among them, is the total amount of carbon emission rights trading; is the actual carbon emission; is the carbon emission quota.

[0089]

[0090] The power grid interaction cost model is:

[0091]

[0092] Among them, 、 are respectively the electricity purchase volume and electricity sales volume of the system within the time period; 、 are respectively the electricity purchase price and the on-grid price.

[0093] The operation and output strategies of each part of the microgrid system with Carnot batteries and stepped carbon trading mechanisms are proposed. The strategies are:

[0094] (1) First, the photovoltaic and wind power output, and renewable energy is consumed as much as possible;

[0095] (2) Secondly, the output of each device is allocated according to the electricity and heat load conditions of the microgrid system;

[0096] (3) If the power generation is excessive, the excess electric energy is stored in the Carnot battery; if the power generation is insufficient, the electric energy is released;

[0097] If the demand still cannot be met, electricity needs to be purchased from the external power grid.

[0098] Embodiment 2

[0099] According to Figure 1 、 2 As shown, this embodiment proposes a microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism. The microgrid system including the Carnot battery and the stepped carbon trading mechanism includes a photovoltaic power generation unit, a wind power generation unit, a combined heat and power unit, a gas boiler, a Carnot battery, and a heat storage tank. In order to meet the electricity and heat demands, the system includes a combined heat and power unit, a gas boiler, and a Carnot battery, and the Carnot battery can supply electricity and heat.

[0100] The present invention constructs an operation model of devices such as a Carnot battery. The Carnot battery can realize the conversion between electricity and heat, flexibly meet the electrical and heat loads of users, and consider the stepped carbon trading mechanism in the operating cost. Taking the single-day operating cost as the target, the microgrid scheduling operation strategy is planned, so as to reduce the system operating cost and achieve the economic and low-carbon operation of the system.

[0101] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates 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. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism, characterized in that Including the following steps: S1: Build a microgrid system with a Carnot battery and a stepped carbon trading mechanism, and establish the equipment models in this system; S2: Establish the daily operating cost model of the microgrid system with a Carnot battery and a stepped carbon trading mechanism; S3: Establish the constraint conditions of the microgrid system with a Carnot battery and a stepped carbon trading mechanism; S4: Based on the above steps, establish a mathematical model for the scheduling optimization of the microgrid system with a Carnot battery and a stepped carbon trading mechanism, and obtain the basic parameters; S5: Construct the operation of the microgrid system and the output strategies of each part; S6: Based on the above steps, establish a mathematical model of a mixed-integer linear programming problem, and use the CPLEX solver and the YALMIP toolbox in Matlab to solve it to obtain the scheduling operation conditions of each device; S7: Solve the model to obtain the scheduling optimization results of the microgrid system, and output the daily operating cost of the microgrid system.

2. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 1, wherein: In the above S1, the microgrid system includes two renewable energy sources, photovoltaic and wind power, a combined heat and power unit, a gas boiler, a Carnot battery, and a heat storage device. The equipment models include a wind power generation model, a photovoltaic power generation model, a combined heat and power unit model, a gas boiler model, a Carnot battery model, and a heat storage device model.

3. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 2, wherein: The wind power generation model is: ， Among them, v t is the instantaneous wind speed, v in , v r and v out are the cut-in wind speed, rated wind speed and cut-out wind speed respectively, P r is the rated power of the wind turbine, P DG is the output power of the wind turbine; The photovoltaic power generation model is: ， Among them, P SP is the output power of the photovoltaic panel, S is the total area of the photovoltaic panel, is the photovoltaic conversion efficiency, and I is the solar irradiance.

4. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 2, characterized in that: The combined heat and power unit model is: ， Among them, P CHP,e and P CHP,h are the electric energy and heat energy output by the cogeneration unit; P GT,e and P GT,h are the electric energy and heat energy output by the gas turbine; P ORC,e is the electric energy output by the low-temperature waste heat power generation device; and are the heat conversion efficiency of the waste heat boiler and the power generation efficiency of the low-temperature waste heat power generation device respectively; and are the efficiencies of converting the natural gas input power of the gas turbine into the output electric energy and heat energy respectively; and are the proportions of the waste heat generated by the gas turbine distributed to the waste heat boiler and the low-temperature waste heat power generation device respectively, and the sum of the two is constantly 1; is the natural gas input to the cogeneration unit; V g is the calorific value of natural gas, 9.88 kWh / m 3 ; The gas boiler model is: ， Among them, P GB,h is the thermal energy output by the gas boiler; is the natural gas input into the gas boiler; is the conversion efficiency of the gas boiler; V g is the calorific value of natural gas, 9.88 kWh / m 3 .

5. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 2, wherein: The Carnot battery model is: ， Among them, S CB is the equivalent storage capacity of the Carnot battery; , , are the charging efficiency, discharging efficiency, and heat supply efficiency of the Carnot battery respectively; , , are the charging amount, discharging amount, and heat release amount of the Carnot battery respectively; The heat storage device model is: ， Among them, S i is the capacity of the heat storage device, , are the heat charging power and the heat discharging power of the heat storage device respectively; , are the heat charging efficiency and the heat discharging efficiency of the heat storage device respectively.

6. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 1, wherein: In the above S2, the daily operating cost model of the microgrid system is: ， Among them, is the gas purchase cost, is the operation and maintenance cost, is the carbon trading cost, is the grid interaction cost; is the total system operation cost; Gas purchase cost The model is as follows: ， Among them, is the natural gas purchase volume during the time period; is the natural gas price during the time period; Operation and maintenance cost The model is as follows: ， Among them, is the operation and maintenance cost coefficient of the i-th device in the system; is the operating power of the i-th device in the system within the cycle; Carbon trading cost Adopt a stepped carbon trading model, which consists of three parts: a carbon emission quota model, an actual carbon emission model, and a stepped carbon emission trading model; Carbon emission quota model: ， Actual carbon emission model: ， Stepped carbon emission trading model: ， Among them, is the total amount of carbon emission rights trading; is the actual carbon emission; is the carbon emission quota; ， The grid interaction cost model is: ， Among them, and are respectively the electricity purchase volume and the electricity sales volume of the system within a time period; and are respectively the electricity purchase price and the on-grid electricity price.

7. A microgrid scheduling optimization method including a Carnot battery and a stepped carbon trading mechanism according to claim 1, characterized in that: In the above S3, the constraint conditions specifically include: The operation of the microgrid system needs to meet the upper and lower limit constraints of each device: ， Electric energy balance constraint: ， Thermal energy balance constraint: ， Natural gas balance constraint 。 8. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 1, characterized in that: In the above S4, based on the system model, objective function, and constraint conditions proposed in S1 - S3, establish a mathematical model for the scheduling optimization of the microgrid system with a Carnot battery and a stepped carbon trading mechanism, and obtain the initial electrical and thermal load data of the microgrid; obtain the typical daily wind power, photovoltaic data, time-of-use electricity price, and gas price data; obtain the basic parameters such as the operation efficiency, rated power, start-stop time of the equipment.

9. The microgrid scheduling optimization method with a Carnot battery and a stepped carbon trading mechanism according to claim 1, characterized in that: In the above S5, the strategy is: First, the photovoltaic and wind power output, and renewable energy is consumed as much as possible; secondly, the output of each device is allocated according to the electrical and thermal load conditions of the microgrid system; when the power generation is excessive, the excess electric energy is stored in the Carnot battery; When the power generation is insufficient, the electric energy is released; when the demand still cannot be met, electricity is purchased from the external grid.

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