Building system regulation and control method based on electric heat energy complementation

Abstract

The invention discloses a building system regulation and control method based on electric heat energy complementation, and relates to the field of electric energy and heat energy combined regulation and control. The problems that an existing heat supply mode is low in heat supply efficiency and poor in economical efficiency are solved. A power grid, a trough type solar heat collector, a wind generating set, an electric boiler, a phase change heat accumulator, a gas turbine, a waste heat boiler, a gas-fired boiler and a heat exchange device form a heat supply system. According to the heat supply load of a building system, the power grid electricity price in each time period in the heat supply system, the natural gas consumption of a gas turbine, the natural gas consumption of a gas-fired boiler, the power generation power of a trough type solar heat collector and the power generation power of a wind generating set; establishing a multi-objective function aiming at minimizing the economic operation cost, maximizing the renewable energy utilization rate and minimizing the carbon dioxide emission, and establishing a constraint condition to constrain the multi-objective function; and solving the multi-objective function by using a multi-objective optimization algorithm to obtain a day-ahead regulation and control strategy of the heat supply system to the building system. The method is used for heat supply regulation and control.

Description

Technical Field

[0001] This invention relates to the field of combined regulation of electrical and thermal energy. Background Technology

[0002] Traditional building heating methods use gas turbines and waste heat boilers for heating. The gas turbine generates electricity and produces high-temperature flue gas, and the waste heat boiler recovers the heat from the flue gas for heating. The disadvantage of this heating method is that when the heat load is low, the gas turbine and waste heat boiler may be forced to shut down or operate inefficiently. It cannot generate more electricity when the electricity price is low and less electricity when the electricity price is high, resulting in low heating efficiency. Another traditional method is to use electric boilers for heating, but electric boilers use electricity from the grid, which is expensive and uneconomical. Summary of the Invention

[0003] The purpose of this invention is to solve the problems of low heating efficiency and poor economy in current heating methods that use gas turbines with waste heat boilers or electric boilers. This invention proposes a building system control method based on complementary electric and thermal energy.

[0004] A building system control method based on electrothermal energy complementarity, the method comprising the following:

[0005] Step 1: Assemble a heating system consisting of a power grid, parabolic trough solar collectors, wind turbine generators, electric boilers, phase change thermal storage devices, gas turbines, waste heat boilers, gas boilers, and heat exchange devices.

[0006] Step 2: Based on the building system's heating load, the grid electricity price at different times in the heating system, the natural gas consumption of the gas turbine, the natural gas consumption of the gas boiler, the power generation of the parabolic trough solar collector, and the power generation of the wind turbine, establish a multi-objective function with the objectives of minimizing economic operating costs, maximizing renewable energy utilization, and minimizing carbon dioxide emissions, and establish constraints to constrain the multi-objective function.

[0007] Step 3: Solve the multi-objective function using a multi-objective optimization algorithm to obtain the control strategy of the daytime heating system on the building system heating.

[0008] Preferably, the parabolic trough solar collector includes a parabolic reflector, a parabolic trough solar collector tube, a heat transfer medium, and a solar tracking system;

[0009] Parabolic trough solar collector tubes consist of multiple solar collector tubes arranged in an array.

[0010] Parabolic reflectors converge and reflect sunlight onto trough-type solar collector tubes located at the focal line. The solar collector tubes absorb solar energy to heat the heat transfer medium. At the same time, the solar tracking system controls the hourly tracking process of the solar collector to maximize the absorption of solar energy.

[0011] The total area of ​​the trough-type solar collector tubes is expressed as follows:

[0012] ,

[0013] In the formula, This represents the total area of ​​the trough-type solar collector tubes. The average heat load of the building, This represents the average daily solar radiation during the heating season. For solar energy guarantee rate, This represents the average heat collection efficiency of the parabolic trough solar collector tube. This refers to the heat loss rate of the pipeline system and heat storage equipment.

[0014] Preferably, the phase change heat storage device is:

[0015] ,

[0016] In the formula, , These represent the amount of heat stored in the heat storage device before and after heat storage / release, respectively. The self-loss heat energy coefficient for heat storage device to dissipate heat to the environment; The amount of heat stored / released; For heat storage / release efficiency.

[0017] Preferably, the electric boiler is:

[0018] ,

[0019] In the formula, For the heating supply of the electric boiler, This indicates the electrothermal conversion efficiency of the electric boiler.

[0020] Preferably, the multi-objective function is:

[0021] ,

[0022] In the formula, For economic operating costs, For renewable energy utilization rate, This refers to carbon dioxide emissions. for Time-of-use electricity price for Power purchased by the power grid during a given time period for Natural gas prices during specific time periods for Natural gas consumption of gas turbines during specific time periods. for Natural gas consumption of gas-fired boilers during certain periods. for Power generation of time-lapse trough solar collectors for Wind power generation capacity during different time periods For power grid emission factors, This is a natural gas emission factor.

[0023] Preferably, the constraints include power balance constraints, thermal balance constraints, electric boiler constraints, and heat storage constraints.

[0024] Preferably, power balance constraints:

[0025] ,

[0026] In the formula, the subscript Indicates the first Each scheduling period This indicates the operating electrical power of the building's photovoltaic power generation system; This indicates the electrical power consumed by the electric boiler; Indicates the electrical load power of the building system; This indicates the electrical power consumption of the solar collector. This indicates the electrical power consumption of the building-type heat exchange unit.

[0027] Thermodynamic equilibrium constraints:

[0028] ,

[0029] In the formula, For the efficiency of electric boilers, For the electrical efficiency of gas turbines, For the efficiency of waste heat boilers, To meet heat load requirements;

[0030] Electric boiler constraints:

[0031] ,

[0032] ,

[0033] In the formula, This indicates the electrothermal conversion efficiency of the electric boiler. Indicates the upper limit of the electric power of the electric boiler;

[0034] Heat storage constraints:

[0035] ,

[0036] ,

[0037] In the formula, This represents the initial heat storage capacity of the nth heat accumulator; Indicates the initial heat storage coefficient; Indicates the heat storage capacity of the heat accumulator. express The amount of heat stored in the nth heat accumulator during the time period; express The heat storage capacity of the nth heat accumulator during time period -1; express The heat storage and release capacity of the time-period heat storage device.

[0038] The beneficial effects of this invention are:

[0039] This invention integrates a power grid, a parabolic trough solar collector, a wind turbine generator, an electric boiler, a phase change thermal storage device, a gas turbine, a waste heat boiler, a gas boiler, and a heat exchange device into a unified system for optimized scheduling. When wind and solar resources are abundant, the model prioritizes using renewable energy to power the electric boiler for heating, while reducing the operation of the gas turbine and gas boiler. When electricity prices are low, electricity is purchased from the grid, and the gas turbine generates more power, while the thermal storage device stores the waste heat it produces. When the heat load is low and electricity prices are high, the gas turbine can generate less or no power, and the demand can be met by consuming previously stored heat or starting the gas boiler. Therefore, this invention offers flexible control, excellent economic efficiency, maximizes the utilization of renewable energy, and effectively reduces wind curtailment. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of a building system control method based on complementary electrothermal energy.

[0041] Figure 2 This is a flowchart of a building system control method based on complementary electrothermal energy. Detailed Implementation

[0042] 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 embodiments of the present invention, and not all embodiments. 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.

[0043] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0044] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0045] Example:

[0046] A building system control method based on electrothermal energy complementarity, characterized in that the method includes the following:

[0047] Step 1: Assemble a heating system consisting of a power grid, parabolic trough solar collectors, wind turbine generators, electric boilers, phase change thermal storage devices, gas turbines, waste heat boilers, gas boilers, and heat exchange devices.

[0048] Step 2: Based on the building system's heating load, the grid electricity price at different times in the heating system, the natural gas consumption of the gas turbine, the natural gas consumption of the gas boiler, the power generation of the parabolic trough solar collector, and the power generation of the wind turbine, establish a multi-objective function with the objectives of minimizing economic operating costs, maximizing renewable energy utilization, and minimizing carbon dioxide emissions, and establish constraints to constrain the multi-objective function.

[0049] Step 3: Solve the multi-objective function using a multi-objective optimization algorithm to obtain the control strategy of the daytime heating system on the building system.

[0050] Specifically, the wind turbine generator set refers to a small wind turbine generator set installed in a building system.

[0051] Preferably, the parabolic trough solar collector includes a parabolic reflector, a parabolic trough solar collector tube, a heat transfer medium, and a solar tracking system;

[0052] Parabolic trough solar collector tubes consist of multiple solar collector tubes arranged in an array.

[0053] Parabolic reflectors converge and reflect sunlight onto trough-type solar collector tubes located at the focal line. The solar collector tubes absorb solar energy to heat the heat transfer medium. At the same time, the solar tracking system controls the hourly tracking process of the solar collector to maximize the absorption of solar energy.

[0054] The total area of ​​the trough-type solar collector tubes is expressed as follows:

[0055] ,

[0056] In the formula, This represents the total area of ​​the trough-type solar collector tubes. The average heat load of the building, This represents the average daily solar radiation during the heating season. For solar energy guarantee rate, This represents the average heat collection efficiency of the parabolic trough solar collector tube. This refers to the heat loss rate of the pipeline system and heat storage equipment.

[0057] Specifically, since parabolic trough solar collectors are arranged in an array, varying degrees of shading will inevitably occur between the collectors as the solar altitude angle changes, reducing the amount of solar radiation projected onto the collector's light-receiving port. Therefore, a reasonable installation spacing must be maintained during installation to minimize shading losses. To facilitate a reasonable study of the shading effect of parabolic trough solar collectors, a shading correction coefficient ζ is used for analysis.

[0058] Further defining the phase change heat storage model is as follows:

[0059] ,

[0060] In the formula, , These represent the amount of heat stored in the heat storage device before and after heat storage / release, respectively. The self-loss heat energy coefficient for heat storage device to dissipate heat to the environment; The amount of heat stored / released; For heat storage / release efficiency.

[0061] Specifically, the principle behind the phase change thermal storage model is as follows: Due to the inconsistency between solar radiation and building load, solar heating systems must be equipped with thermal storage devices to store excess heat when solar radiation is abundant and release it to provide heating for users when radiation is insufficient, thereby achieving a reasonable match between solar energy and building load.

[0062] A thermal accumulator provides either thermal energy output or storage according to system needs. A model is established from the perspective of energy conservation, defining the thermal energy variables of the energy storage device before and after thermal storage (release), the process variables of thermal energy storage (release), and the thermal storage (release) efficiency. This model then shows the relationship between the changes in the thermal energy stored in the device before and after thermal storage (release).

[0063] Further specifying, the electric boiler model is as follows:

[0064] ,

[0065] In the formula, For the heating supply of the electric boiler, This indicates the electrothermal conversion efficiency of the electric boiler.

[0066] Specifically, an electric boiler is a device that converts electrical energy into heat energy by consuming electricity generated by photovoltaic power generation. As a direct electric heating device, the modeling process for a thermal storage electric boiler only requires conducting electrothermal efficiency experiments. Based on the experimental data, the electrothermal efficiency is derived, thus establishing a mathematical model of its electrothermal conversion characteristics. Its heat storage function is not primarily utilized in the system; therefore, a mathematical model of the variable-condition heat storage characteristics of the thermal storage electric boiler is established based on the concept of a phase change thermal accumulator.

[0067] Further defining the objective function, the multi-objective function is:

[0068] ,

[0069] In the formula, For economic operating costs, For renewable energy utilization rate, This refers to carbon dioxide emissions. for Time-of-use electricity price for Power purchased by the power grid during a given time period for Natural gas prices during specific time periods for Natural gas consumption of gas turbines during specific time periods. for Natural gas consumption of gas-fired boilers during certain periods. for Power generation of time-lapse trough solar collectors for Wind power generation capacity during different time periods For power grid emission factors, This is a natural gas emission factor.

[0070] Further restrictions are imposed, including constraints on power balance, thermal balance, electric boilers, and thermal accumulators.

[0071] Further restrictions, power balance constraints:

[0072] ,

[0073] In the formula, the subscript Indicates the first Each scheduling period This indicates the operating electrical power of the building's photovoltaic power generation system; This indicates the electrical power consumed by the electric boiler; Indicates the electrical load power of the building system; This indicates the electrical power consumption of the solar collector. This indicates the electrical power consumption of the building-type heat exchange unit.

[0074] Thermodynamic equilibrium constraints:

[0075] ,

[0076] In the formula, For the efficiency of electric boilers, For the electrical efficiency of gas turbines, For the efficiency of waste heat boilers, To meet heat load requirements;

[0077] Electric boiler constraints:

[0078] ,

[0079] ,

[0080] In the formula, This indicates the electrothermal conversion efficiency of the electric boiler. Indicates the upper limit of the electric power of the electric boiler;

[0081] Heat storage constraints:

[0082] ,

[0083] ,

[0084] In the formula, This represents the initial heat storage capacity of the nth heat accumulator; Indicates the initial heat storage coefficient; Indicates the heat storage capacity of the heat accumulator. express The amount of heat stored in the nth heat accumulator during the time period; express The heat storage capacity of the nth heat accumulator during time period -1; express The heat storage and release capacity of the time-period heat storage device.

[0085] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A building system control method based on complementary electrothermal energy, characterized in that, The method includes the following: Step 1: Assemble a heating system consisting of a power grid, parabolic trough solar collectors, wind turbine generators, electric boilers, phase change thermal storage devices, gas turbines, waste heat boilers, gas boilers, and heat exchange devices. Step 2: Based on the building system's heating load, the grid electricity price at different times in the heating system, the natural gas consumption of the gas turbine, the natural gas consumption of the gas boiler, the power generation of the parabolic trough solar collector, and the power generation of the wind turbine, establish a multi-objective function with the objectives of minimizing economic operating costs, maximizing renewable energy utilization, and minimizing carbon dioxide emissions, and establish constraints to constrain the multi-objective function. Step 3: Solve the multi-objective function using a multi-objective optimization algorithm to obtain the control strategy of the daytime heating system on the building system heating.

2. The building system control method based on electrothermal energy complementarity according to claim 1, characterized in that, Parabolic trough solar collectors include parabolic reflectors, parabolic trough solar collector tubes, heat transfer medium, and solar tracking system; Parabolic trough solar collector tubes consist of multiple solar collector tubes arranged in an array. Parabolic reflectors converge and reflect sunlight onto trough-type solar collector tubes located at the focal line. The solar collector tubes absorb solar energy to heat the heat transfer medium. At the same time, the solar tracking system controls the hourly tracking process of the solar collector to maximize the absorption of solar energy. The total area of ​​the trough-type solar collector tubes is expressed as follows: ， In the formula, This represents the total area of ​​the trough-type solar collector tubes. The average heat load of the building, This represents the average daily solar radiation during the heating season. For solar energy guarantee rate, This represents the average heat collection efficiency of the parabolic trough solar collector tube. This refers to the heat loss rate of the pipeline system and heat storage equipment.

3. The building system control method based on electrothermal energy complementarity according to claim 1, characterized in that, The phase change heat storage device is: ， In the formula, , These represent the amount of heat stored in the heat storage device before and after heat storage / release, respectively. The self-loss heat energy coefficient for heat storage device to dissipate heat to the environment; The magnitude of heat storage / release; For heat storage / release efficiency.

4. The building system control method based on electrothermal energy complementarity according to claim 1, characterized in that, The electric boiler is: ， In the formula, For the heating supply of the electric boiler, This indicates the electrothermal conversion efficiency of the electric boiler.

5. A building system control method based on complementary electrothermal energy according to claim 1, characterized in that, The multi-objective function is: ， In the formula, For economic operating costs, For renewable energy utilization rate, This refers to carbon dioxide emissions. for Time-of-use electricity price for Power purchased by the power grid during a given time period for Natural gas prices during specific time periods for Natural gas consumption of gas turbines during specific time periods. for Natural gas consumption of gas-fired boilers during certain periods. for Power generation of time-slot solar collectors for Wind power generation capacity during different time periods For power grid emission factors, This is a natural gas emission factor.

6. A building system control method based on complementary electrothermal energy according to claim 5, characterized in that, The constraints include power balance constraints, thermal balance constraints, electric boiler constraints, and thermal accumulator constraints.

7. A building system control method based on complementary electrothermal energy according to claim 6, characterized in that, Power balance constraints: ， In the formula, the subscript Indicates the first Each scheduling period This indicates the operating electrical power of the building's photovoltaic power generation system; This indicates the electrical power consumed by the electric boiler; Indicates the electrical load of the building system; This indicates the electrical power consumption of the solar collector. This indicates the electrical power consumption of the building-type heat exchange unit. Thermodynamic equilibrium constraints: ， In the formula, For the efficiency of electric boilers, For the electrical efficiency of gas turbines, For the efficiency of waste heat boilers, To meet heat load requirements; Electric boiler constraints: ， ， In the formula, This indicates the electrothermal conversion efficiency of the electric boiler. Indicates the upper limit of the electric power of the electric boiler; Heat storage constraints: ， ， In the formula, This represents the initial heat storage capacity of the nth heat accumulator; Indicates the initial heat storage coefficient; Indicates the heat storage capacity of the heat accumulator. express The amount of heat stored in the nth heat accumulator during the time period; express The heat storage capacity of the nth heat accumulator during time period -1; express The heat storage and release capacity of the time-period heat storage device.

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