All-renewable energy multi-energy complementary coupling energy supply system based on biomass energy and its scheduling strategy optimization model

Abstract

The present invention discloses a fully renewable energy multi-energy complementary coupling energy supply system based on biomass energy and a scheduling strategy optimization model thereof. The system utilizes four renewable primary energy sources to meet the needs of users of a certain scale for electric load (17), heat load (15), cold load (14), and gas load (13) through energy conversion, energy transmission, and energy storage; wind energy (1), biogas biomass energy (2), solar energy (3), gasified biomass energy (4), direct combustion biomass energy (5), and geothermal energy (6) are converted into secondary energy through energy conversion equipment and sent to corresponding electric buses (21), heat buses (16), cold buses (10), and gas buses (9) to supply users and energy storage equipment. The objective function of the scheduling strategy optimization model requires that the total annual cost of the system is minimized. The system of the present invention utilizes local renewable energy, has stable energy supply, reduces carbon emissions, avoids impact on large power grids, and has good economic efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of renewable energy utilization, in particular to a biomass energy-based all-renewable energy multi-energy complementary coupling energy supply system and a scheduling strategy optimization model thereof. Background Art

[0002] The National Development and Reform Commission and the National Energy Administration issued the "Implementation Opinions on Promoting the Construction of Multi-energy Complementary Integrated Optimization Demonstration Projects", which clearly defined the goal of accelerating the construction of multi-energy complementary integrated optimization demonstration projects. Relevant theoretical and technological achievements have been applied at home and abroad, and diverse demonstration projects have been built, including multi-energy complementarity, distributed energy, microgrids, and combined heat and cold power generation. The relevant work is different and can also learn from each other. The "Action Plan for Peaking Carbon by 2030" requires strict control of the scale of cross-regional transmission of renewable energy power supporting coal-fired power, and the proportion of renewable energy power in newly built channels should not be less than 50% in principle.

[0003] The existing multi-energy complementary coupling energy supply system mostly relies on fossil energy to ensure the stability of energy supply, and the proportion of renewable energy in the system is low, which is easy to cause excessive CO2 emissions. Biomass energy can continuously and controllably output heat and electricity, forming a fully renewable energy multi-energy complementary coupling energy supply system based on biomass energy, which is expected to achieve 100% renewable energy.

[0004] Establishing a fully renewable energy, multi-energy complementary coupling energy supply system based on biomass energy is the only way to fill the shortcomings and weaknesses of my country's energy system under the "dual carbon" goals, promote green and low-carbon transformation, and achieve the "dual carbon" goals. Summary of the invention

[0005] The purpose of the present invention is to provide a biomass-based all-renewable energy multi-energy complementary coupling energy supply system and its scheduling strategy optimization model in response to the problems existing in the prior art; the system combines the resource endowment of the energy-consuming area, couples a variety of local renewable energy sources, realizes the full renewable energy supply of the system, and at the same time ensures the stable energy supply of the system and reduces carbon emissions; and through the reasonable configuration of the installed capacity of the unit, forms a scheduling strategy for stable energy supply.

[0006] The purpose of the present invention is to be solved by the following technical solutions:

[0007] A fully renewable energy multi-energy complementary coupling energy supply system based on biomass energy, characterized in that: the system utilizes four renewable primary energy sources, namely biomass energy, wind energy, solar energy and geothermal energy, and meets the needs of users of a certain scale for electric load, heat load, cooling load and gas load through energy conversion, energy transmission and energy storage; among them, wind energy converts part of local wind resources into electric energy through wind turbines and then connects to the electric bus; part of biogas biomass energy is converted into electric energy through biogas generators and then enters the electric bus, and the rest is sent to the gas bus; part of solar energy converts part of local solar energy resources into electric energy through photovoltaic generators and then connects to the electric bus; part of gasified biomass energy is converted into electric energy through cogeneration units and then enters The power bus is connected to the cogeneration unit, which generates a certain amount of heat according to the corresponding heat-to-electricity ratio and enters the heat bus with water as the working fluid, and the rest is sent to the gas bus; direct-fired biomass energy uses a biomass direct-fired boiler to obtain heat in the form of direct combustion heating and enters the heat bus with water as the working fluid; geothermal energy is converted into heat in the form of a heat pump through a ground source heat pump in winter and the heat is sent to the heat bus with water as the working fluid, and in summer, the indoor heat is introduced into the ground through a ground source heat pump in the form of a heat pump, and the generated cold enters the cold bus with water as the working fluid; the power bus is connected to the power storage unit, the local consumption interface and the power load; the hot bus is connected to the heat storage unit and the heat load; the cold bus is connected to the cold storage unit and the cold load; the gas bus is connected to the gas storage unit and the gas load.

[0008] The biogas biomass energy can obtain biomass raw gas by anaerobic / aerobic fermentation in a fermentation tank, and then obtain clean biomass gas by a biogas biomass purification unit. A part of the clean biomass gas is converted into electrical energy by a biogas generator set and then enters the electric bus, and the rest of the clean biomass gas is sent to the gas bus.

[0009] The gasified biomass energy can obtain biomass raw fuel gas by gasification in a biomass gasification furnace, and then obtain clean biomass fuel gas through a gasification biomass purification unit. Part of the clean biomass fuel gas is converted into electrical energy through a cogeneration unit and then enters the electric bus. The cogeneration unit generates a certain amount of heat according to the corresponding heat-to-electricity ratio and enters the heat bus with water as the working fluid, and then the remaining clean biomass fuel gas is sent to the gas bus.

[0010] The hot bus is connected to an absorption refrigeration unit, and the absorption refrigeration unit utilizes the heat of the hot bus to generate cold energy and transmits it to the cold bus.

[0011] The scheduling strategy optimization model of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy is characterized in that the objective function of the scheduling strategy optimization model requires the sum of the annual investment cost, annual operating cost, annual maintenance cost and annual carbon tax of the system to be minimized. The objective function of the scheduling strategy optimization model is:

[0012]

[0013] In formula (1), TAC is the total annual cost of the system, RMB; IC i is the annual investment cost of the i-th unit, yuan; MC i,m,h is the maintenance cost of the i-th unit at the h-th hour in the m-th month, RMB; OC i,m,h is the operating cost of the i-th unit at the h-th hour in the m-th month, RMB; CE i,m,h is the carbon tax paid by the ith unit for carbon emissions in the hth hour of the mth month, RMB; i is the type of unit, which includes wind power generation unit, biomass biogas power generation unit, photovoltaic power generation unit, biomass gasification cogeneration unit, biomass direct-fired heating unit, ground source heat pump unit, power storage unit, heat storage unit, absorption refrigeration unit, cold storage unit and gas storage unit, among which the wind power generation unit includes wind turbine generator set, the biomass biogas power generation unit includes fermentation tank, biogas biomass purification unit and biogas generator set, the photovoltaic power generation unit includes photovoltaic generator set, the biomass gasification cogeneration unit includes biomass gasification furnace, gasification biomass purification unit and cogeneration unit, the biomass direct-fired heating unit includes biomass direct-fired boiler, and the ground source heat pump unit includes ground source heat pump.

[0014] Annual investment cost IC of the i-th unit i The annualized value is obtained by multiplying the rated capacity of the i-th unit by the kilowatt cost of the i-th unit, as shown in formula (2):

[0015]

[0016] In formula (2), IC i is the annual investment cost of the i-th unit; g is the annual interest rate of capital investment; y is the useful life of the equipment; RC i is the capacity configuration of the i-th unit, kW; UP i is the kilowatt cost of the i-th unit investment, yuan / kW.

[0017] The annual operating cost OC of the i-th unit i It is determined by the raw materials consumed and the price of raw materials during the output process when the i-th unit participates in the system energy scheduling, as shown in formula (3):

[0018]

[0019] In formula (3), OC i represents the annual operating cost of the i-th unit; EO BCHP,m,h The power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass gasification cogeneration unit; CV BRMis the calorific value of biomass raw materials, kJ / kg; P BRM，m is the unit price of biomass raw materials, yuan / kg; EO BPG,m,h The power output of the biomass gas power generation unit in the hth hour of the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass biogas power generation unit; CV KW is the calorific value of kitchen waste, kJ / kg; P KW,m The subsidy price for the collection, transportation and treatment of restaurant kitchen waste is RMB / kg; HO BDCH,m,h is the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; is the heat conversion efficiency of the biomass direct-fired heating unit; CV BRM is the calorific value of biomass raw material, kJ / kg;.

[0020] The annual maintenance cost MC of the i-th unit i It is determined by the output size and unit maintenance cost of the i-th unit when it participates in system energy dispatch, as shown in formula (4):

[0021]

[0022] In formula (4), MC i is the annual maintenance cost of the i-th unit; EO i,m,h is the power output of the i-th unit at the h-th hour in the m-th month during power scheduling, kW; HO i,m,h is the heat output of the i-th unit in the m-th month and the h-th hour during heat scheduling, kW; CO i,m,h P is the cooling capacity output by the i-th unit in the h-th hour of the m-th month during cooling capacity scheduling, kW; i is the unit maintenance cost when the i-th unit participates in scheduling, RMB / kW.

[0023] The annual carbon tax amount CE of the i-th unit i It is determined by the carbon dioxide emissions and unit carbon tax when the i-th unit participates in system energy scheduling, as shown in formula (5):

[0024]

[0025] In formula (5), CE i is the annual carbon tax amount of the i-th unit; α i is the carbon dioxide emission conversion coefficient of the ith unit when participating in power dispatch, kg / kW; β i is the carbon dioxide emission conversion coefficient of the ith unit when participating in heat dispatch output, kg / kW; δ iis the carbon dioxide emission conversion coefficient when the i-th unit participates in cooling capacity scheduling, kg / kW; η is the carbon dioxide emission tax, yuan / kg.

[0026] The constraints of the objective function of the scheduling strategy optimization model include power balance constraint, heat balance constraint, and cooling balance constraint, wherein the power balance constraint is shown in formula (6):

[0027]

[0028] In formula (6): EO BCHP,m,h It represents the power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power scheduling, kW; EO PV,m,h Indicates the power output of the photovoltaic power generation unit at the hth hour in the mth month during power scheduling, kW; EO WT,m,h It represents the power output of the wind power generation unit at the hth hour in the mth month during power dispatch, kW; EO BPG,m,h It represents the power output of the biomass gas power generation unit at the hth hour in the mth month during power scheduling, kW; EO SBT,m,h Indicates the amount of electricity output at the hth hour in the mth month during the electricity storage unit dispatch, kW; UEL m,h Indicates the amount of electricity consumed by the user's electrical load at the hth hour in the mth month, kW; EC GSHP,,m,h Indicates the power consumed by the ground source heat pump unit at the hth hour in the mth month, kW; EC CS,m,h Indicates the power consumed by the cold storage unit during the cold storage process at the hth hour in the mth month, kW; EC CSR,m,h Indicates the power consumption of the cold storage unit during the cooling process at the hth hour in the mth month, kW; EC SBT,m,h Indicates the amount of electricity stored in the power storage unit at the hth hour in the mth month, kW;

[0029] The heat balance constraint is shown in formula (7):

[0030] HO BCHP,m,h +HO GSHP,m,h +HO BDCH,m,h +HO HS,m,h =UHL m,h +HC AC,m,h +HC HS,m,h (7)

[0031] In formula (7), HO BCHP,m,h Indicates the heat output of the biomass gasification cogeneration unit at the hth hour in the mth month during heat scheduling, kW; HO GSHP,m,h Indicates the heat output of the ground source heat pump unit at the hth hour in the mth month during heat scheduling, kW; HO BDCH,m,hIndicates the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; HO HS,m,h Indicates the heat output of the heat storage unit at the hth hour in the mth month during heat scheduling, kW; UHL m,h Indicates the heat consumed in the hth hour of the mth month during the heat load scheduling on the user side, kW; HC AC,m,h Indicates the heat consumed by the absorption refrigeration unit in the hth hour of the mth month during heat scheduling, kW; HC HS,m,h It represents the heat stored in the hth hour of the mth month during the heat scheduling of the heat storage unit, kW;

[0032] The cooling balance constraint is shown in formula (8):

[0033] CO GSHP,m,h +CO AC,m,h +CO CS,m,h =UCL m,h +CC CS,m,h (8)

[0034] In formula (8), CO GSHP,m,h Indicates the cooling capacity output at the hth hour in the mth month during the cooling capacity scheduling of the ground source heat pump unit, kW; CO AC,m,h Indicates the cooling capacity output of the absorption refrigeration unit at the hth hour in the mth month during cooling capacity scheduling, kW; CO CS,m,h It indicates the cooling capacity output at the hth hour in the mth month during the cooling capacity scheduling of the cold storage unit, kW; UCL m,h Indicates the cooling capacity consumed in the hth hour of the mth month during the cooling load scheduling on the user side, kW; CC CS,m,h It indicates the cooling capacity stored at the hth hour in the mth month during cooling capacity scheduling of the cooling storage unit, in kW.

[0035] The four renewable energy sources involved in the system are converted into secondary energy through six energy conversion units, among which the biomass energy utilization units include: biomass biogas power generation unit, biomass gasification cogeneration unit and biomass direct-fired heating unit. Based on the objective function of the scheduling strategy optimization model, the relative installed capacity ratio of the biomass biogas power generation unit is 10% to 50%, the relative installed capacity ratio of the biomass gasification cogeneration unit is 60% to 100%, and the relative installed capacity ratio of the biomass direct-fired heating unit is 60% to 80%; the relative installed capacity ratio of the wind power generation unit is 20% to 100%, the relative installed capacity ratio of the photovoltaic power generation unit is 20% to 100%, the relative installed capacity ratio of the ground source heat pump unit is 20% to 60%, and the relative installed capacity ratio of the absorption refrigeration unit is 50% to 200%.

[0036] In the system described in the patent of this invention, the ratio of the installed capacity of the corresponding energy production or energy conversion unit to the annual maximum energy load on the user side is the relative installed capacity ratio. That is, the relative installed capacity ratio refers to the ratio of the installed capacity of a certain unit to the total load (multiplying the heat load, cold load, and gas load by the corresponding coefficients to convert them into electrical loads; the specific calculation process is: first assume that the heat load is supplied by coal, then calculate the speed of consuming standard coal under this load, and then convert the standard coal into electrical load, and the same idea applies to other loads).

[0037] Based on the objective function of the scheduling strategy optimization model, each day is divided into two energy consumption peak periods and one energy consumption valley period: the energy load of the first energy consumption peak period accounts for about 40% of the total load of the whole day, which is from 0:00 to 8:00 every day; the energy load of the energy consumption valley period accounts for about 10% of the total load of the whole day, which is from 9:00 to 16:00; the energy load of the second energy consumption peak period accounts for about 50% of the total load of the whole day, which is from 17:00 to 24:00 every day. The local consumption rates of the local consumption interface during the first peak electricity consumption period, the trough electricity consumption period and the second peak electricity consumption period are: during the first peak electricity consumption period, the local consumption rate in summer is 30%-40%, the local consumption rate in the transition season is 5%-10%, and the local consumption rate in winter is 35%-45%; in the trough electricity consumption period, the local consumption rate in summer is 60%-70%, the local consumption rate in the transition season is 10%-20%, and the local consumption rate in winter is 60%-70%; during the second peak electricity consumption period, the local consumption rate in summer is 30%-40%, the local consumption rate in the transition season is 5%-10%, and the local consumption rate in winter is 30%-40%.

[0038] In the present invention, the system meets the needs of a certain scale of users for electric load, heat load, cooling load and gas load through energy conversion, energy transmission and energy storage, and defines the local consumption rate as the ratio of the local consumption of secondary energy to the total output. For example, if the system plans to supply energy to 1,000 residential areas, the electricity not used by the users will be sent to other local users through the local consumption interface, so the ratio of the electricity used for other users to the total electricity generated by the system is the local consumption rate.

[0039] The local consumption rate reflects the quality of the system's dispatching strategy and the rationality of the system configuration. The lower the local consumption rate, the more reasonable the system's dispatching strategy is during this period, and vice versa. The main reason for using the local consumption rate to illustrate the dispatching strategy is that the system's dispatching strategy is based on the principle of minimizing the objective function of the dispatching strategy optimization model in combination with load, wind speed and solar radiation intensity. It is highly random and has poor regularity, and it is impossible to form a completely unified dispatching strategy. Therefore, the calculation of the local consumption rate reflects the quality of the energy dispatching rate.

[0040] The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy is mainly deployed in the eastern region of my country, including Hebei Province, Beijing, Tianjin, Shandong Province, Jiangsu Province, Zhejiang Province, and Shanghai. The renewable energy in the system includes wind energy, biomass energy, solar energy, geothermal energy, etc., and the types of renewable energy must reach three or more. All energy in the system is renewable energy, and non-renewable energy such as coal, oil, and natural gas cannot appear. The system can simultaneously meet the user's cooling load, heating load, electricity load, and gas load needs.

[0041] Compared with the prior art, the present invention has the following advantages:

[0042] The sum of the relative installed capacity ratios of the biomass biogas power generation unit and the biomass gasification cogeneration unit in the system of the present invention is no more than 150%, and the problem of excessive installed capacity of the power storage unit is avoided, which not only ensures the stability of the system energy supply, but also makes the system more economical.

[0043] The system of the present invention couples four kinds of renewable energy sources, and meets the needs of users of a certain scale for electric load, heat load, cooling load and gas load through energy conversion, energy transmission and energy storage; the secondary energy generated by the system is mostly consumed by the user-side load, and a small amount of excess secondary energy is consumed locally through city grid coupling, so the local consumption rate of the system is low, and there is no situation of selling electricity across walls; the system makes full use of local renewable energy, has stable energy supply, reduces carbon emissions, avoids impact on large power grids, and has good economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Attached Figure 1 The energy flow diagram of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy of the present invention;

[0045] Attached Figure 2 The summer scheduling strategy of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to the first embodiment of the present invention;

[0046] Attached Figure 3 The transition season scheduling strategy of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to the first embodiment of the present invention;

[0047] Attached Figure 4 This is the winter scheduling strategy for the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to the first embodiment of the present invention.

[0048] Among them: 1-wind energy; 2-biogas biomass energy; 3-solar energy; 4-gasified biomass energy; 5-direct combustion biomass energy; 6-geothermal energy; 7-biomass direct combustion boiler; 8-ground source heat pump; 9-gas bus; 10-cold bus; 11-gas storage unit; 12-absorption refrigeration unit; 13-gas load; 14-cold load; 15-heat load; 16-heat bus; 17-electric load; 18-heat storage unit; 19-on-site consumption interface; 20-electricity storage unit; 21-electric bus; 22-cogeneration unit; 23-photovoltaic generator set; 24-biogas generator set; 25-wind turbine; 26-biogas biomass purification unit; 27-gasified biomass purification unit; 28-fermentation tank; 29-biomass gasification furnace; 30-cold storage unit. DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0050] In the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy and its dispatch strategy optimization model provided by the present invention, the physical model and economic model of each unit are first established. The physical model ensures that each unit is in accordance with the attached Figure 1 The energy flow diagram shown in the figure is connected to ensure energy balance; the economic model can ensure that the total annual cost of the system (also called the objective function, including the annual investment cost of each unit, annual operating cost, annual maintenance cost, and carbon tax cost) is calculated according to the energy flow balance process, and the mixed integer linear programming rule will select the energy balance solution with the smallest objective function value among many energy balance solutions, that is, the most cost-effective energy balance solution. This energy balance solution includes the installed capacity (configuration) of each unit and the energy scheduling strategy of each unit during the energy balance process.

[0051] like Figure 1As shown: a fully renewable energy multi-energy complementary coupling energy supply system based on biomass energy, the system utilizes four renewable primary energy sources, namely biomass energy, wind energy 1, solar energy 3, and geothermal energy 6, and meets the needs of users of a certain scale for electric load 17, thermal load 15, cooling load 14, and gas load 13 through energy conversion, energy transmission, and energy storage. Wind energy 1 converts part of the local wind resources into electric energy through wind turbine 25 and then connects to electric bus 21; biogas biomass energy 2 uses fermentation tank 28 to obtain biomass raw gas by anaerobic / aerobic fermentation, and then obtains clean biomass gas through biogas biomass purification unit 26, converts part of the clean biomass gas into electric energy through biogas generator 24 and then enters electric bus 21, and then sends the rest of the clean biomass gas into gas bus 9; solar energy 3 converts part of the local solar energy resources into electric energy through photovoltaic generator 23 and then connects to electric bus 21; gasification biomass energy 4 uses biomass gasification furnace 29 to obtain biomass raw gas by gasification, and then obtains clean biomass gas through gasification biomass purification unit 27, converts part of the clean biomass gas into electric energy through cogeneration unit 22 and then enters electric bus 21, and cogeneration unit 22 generates a certain amount of heat according to the corresponding heat-to-electricity ratio and uses water as working fluid. Enter the hot bus 16, and then send the rest of the clean biomass gas into the gas bus 9; the direct-fired biomass energy 5 uses the biomass direct-fired boiler 7 to obtain heat in a direct-fired heating manner and enters the hot bus 16 with water as the working fluid; the geothermal energy 6 is converted into heat in the winter by the ground source heat pump 8 in the form of a heat pump and the heat is sent to the hot bus 16 with water as the working fluid, and in the summer, the indoor heat is introduced into the underground by the ground source heat pump 8 in the form of a heat pump, and the generated cold enters the cold bus 10 with water as the working fluid; the electric bus 21 is connected to the power storage unit 20, the local consumption interface 19 and the electric load 17; the hot bus 16 is connected to the heat storage unit 18 and the heat load 15, and the hot bus 16 is connected to the absorption refrigeration unit 12 at the same time, and the absorption refrigeration unit 12 uses the heat of the hot bus to generate cold and transmits it to the cold bus 10; the cold bus 10 is connected to the cold storage unit 30 and the cold load 14; the gas bus 9 is connected to the gas storage unit 11 and the gas load 13.

[0052] The dispatch strategy optimization model of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy. The objective function of the dispatch strategy optimization model requires the sum of the system's annual investment cost, annual operating cost, annual maintenance cost and annual carbon tax to be minimized. The objective function of the dispatch strategy optimization model is:

[0053]

[0054] In formula (1), TAC is the total annual cost of the system, RMB; IC i is the annual investment cost of the i-th unit, yuan; MC i,m,his the maintenance cost of the i-th unit at the h-th hour in the m-th month, RMB; OC i,m,h is the operating cost of the i-th unit at the h-th hour in the m-th month, RMB; CE i,m,h is the carbon tax paid by the i-th unit for carbon emissions in the h-th hour of the m-th month, RMB; i is the type of unit, i includes wind power generation unit, biomass biogas power generation unit, photovoltaic power generation unit, biomass gasification cogeneration unit, biomass direct-fired heating unit, ground source heat pump unit, power storage unit 20, heat storage unit 18, absorption refrigeration unit 12, cold storage unit 30 and gas storage unit 11, wherein the wind power generation unit includes a wind generator set 25, the biomass biogas power generation unit includes a fermentation tank 28, a biogas biomass purification unit 26 and a biogas generator set 24, the photovoltaic power generation unit includes a photovoltaic generator set 23, the biomass gasification cogeneration unit includes a biomass gasification furnace 29, a gasification biomass purification unit 27 and a cogeneration unit 22, the biomass direct-fired heating unit includes a biomass direct-fired boiler 7, and the ground source heat pump unit includes a ground source heat pump 8.

[0055] Annual investment cost IC of the i-th unit i The annualized value is obtained by multiplying the rated capacity of the i-th unit by the kilowatt cost of the i-th unit, as shown in formula (2):

[0056]

[0057] In formula (2), IC i is the annual investment cost of the i-th unit; g is the annual interest rate of capital investment; y is the useful life of the equipment; RC i is the capacity configuration of the i-th unit, kW; UP i is the kilowatt cost of the i-th unit investment, yuan / kW.

[0058] The annual operating cost OC of the i-th unit i It is determined by the raw materials consumed and the price of raw materials during the output process when the i-th unit participates in the system energy scheduling, as shown in formula (3):

[0059]

[0060] In formula (3), OC i represents the annual operating cost of the i-th unit; EO BCHP,m,h The power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass gasification cogeneration unit; CV BRM is the calorific value of biomass raw materials, kJ / kg; P BRM，m is the unit price of biomass raw materials, yuan / kg; EO BPG,m,hThe power output of the biomass gas power generation unit in the hth hour of the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass biogas power generation unit; CV KW is the calorific value of kitchen waste, kJ / kg; P KW,m The subsidy price for the collection, transportation and treatment of restaurant kitchen waste is RMB / kg; HO BDCH,m,h is the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; is the heat conversion efficiency of the biomass direct-fired heating unit; CV BRM is the calorific value of biomass raw material, kJ / kg;.

[0061] The annual maintenance cost MC of the i-th unit i It is determined by the output size and unit maintenance cost of the i-th unit when it participates in system energy dispatch, as shown in formula (4):

[0062]

[0063] In formula (4), MC i is the annual maintenance cost of the i-th unit; EO i,m,h is the power output of the i-th unit at the h-th hour in the m-th month during power scheduling, kW; HO i,m,h is the heat output of the i-th unit in the m-th month and the h-th hour during heat scheduling, kW; CO i,m,h P is the cooling capacity output by the i-th unit in the h-th hour of the m-th month during cooling capacity scheduling, kW; i is the unit maintenance cost when the i-th unit participates in scheduling, RMB / kW.

[0064] The annual carbon tax amount CE of the i-th unit i It is determined by the carbon dioxide emissions and unit carbon tax when the i-th unit participates in system energy scheduling, as shown in formula (5):

[0065]

[0066] In formula (5), CE i is the annual carbon tax amount of the i-th unit; α i is the carbon dioxide emission conversion coefficient of the ith unit when participating in power dispatch, kg / kW; β i is the carbon dioxide emission conversion coefficient of the ith unit when participating in heat dispatch output, kg / kW; δ i is the carbon dioxide emission conversion coefficient when the i-th unit participates in cooling capacity scheduling, kg / kW; η is the carbon dioxide emission tax, yuan / kg.

[0067] The constraints of the objective function of the scheduling strategy optimization model include power balance constraint, heat balance constraint, and cooling balance constraint, as shown in formulas (6) to (8).

[0068]

[0069] The power balance constraint is shown in formula (6), where: EO BCHP,m,h It represents the power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power scheduling, kW; EO PV,m,h Indicates the power output of the photovoltaic power generation unit at the hth hour in the mth month during power scheduling, kW; EO WT,m,h It represents the power output of the wind power generation unit at the hth hour in the mth month during power dispatch, kW; EO BPG,m,h It represents the power output of the biomass gas power generation unit at the hth hour in the mth month during power scheduling, kW; EO SBT,m,h It represents the power output of the power storage unit 20 at the hth hour in the mth month during power scheduling, kW; UEL m,h Indicates the amount of electricity consumed by the user-side electric load 17 at the hth hour in the mth month, kW; EC GSHP,,m,h Indicates the power consumed by the ground source heat pump unit at the hth hour in the mth month, kW; EC CS,m,h represents the power consumed by the cold storage unit 30 during the cold storage process at the hth hour in the mth month, kW; EC CSR,m,h represents the power consumption of the cold storage unit 30 during the cooling process at the hth hour in the mth month, kW; EC SBT,m,h Indicates the amount of electricity stored in the power storage unit 20 at the hth hour in the mth month, kW;

[0070] HO BCHP,m,h +HO GSHP,m,h +HO BDCH,m,h +HO HS,m,h =UHL m,h +HC AC,m,h +HC HS,m,h (7)

[0071] The heat balance constraint is shown in formula (7), where HO BCHP,m,h Indicates the heat output of the biomass gasification cogeneration unit at the hth hour in the mth month during heat scheduling, kW; HO GSHP,m,h Indicates the heat output of the ground source heat pump unit at the hth hour in the mth month during heat scheduling, kW; HO BDCH,m,h Indicates the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; HO HS,m,h Indicates the heat output of the heat storage unit 18 at the hth hour in the mth month during heat scheduling, kW; UHL m,hIndicates the heat load on the user side 15 The heat consumed in the hth hour of the mth month during heat scheduling, kW; HC AC,m,h represents the heat consumed by the absorption refrigeration unit 12 at the hth hour in the mth month during heat scheduling, kW; HC HS,m,h represents the amount of heat stored in the heat storage unit 18 at the hth hour in the mth month during heat scheduling, kW;

[0072] CO GSHP,m,h +CO AC,m,h +CO CS,m,h =UCL m,h +CC CS,m,h (8)

[0073] The cooling capacity balance constraint is shown in formula (8), where CO GSHP,m,h Indicates the cooling capacity output at the hth hour in the mth month during the cooling capacity scheduling of the ground source heat pump unit, kW; CO AC,m,h represents the cooling capacity output by the absorption refrigeration unit 12 at the hth hour in the mth month during cooling capacity scheduling, kW; CO CS,m,h It represents the cooling capacity output at the hth hour of the mth month during cooling capacity scheduling of the cooling storage unit 30, kW; UCL m,h Indicates the cooling load on the user side 14 The cooling capacity consumed in the hth hour of the mth month during cooling capacity scheduling, kW; CC CS,m,h It represents the cold capacity stored in the cold storage unit 30 at the hth hour in the mth month during the cold capacity scheduling, in kW.

[0074] Embodiment 1

[0075] A community with 1,000 households in a county in Yancheng City, Jiangsu Province was selected as the energy supply object. The relative installed capacity ratio of biomass gasification cogeneration unit is 60%, the relative installed capacity ratio of biomass biogas power generation unit is 10%, the relative installed capacity ratio of biomass direct combustion heating unit is 60%, the relative installed capacity ratio of wind power generation unit is 100%, the relative installed capacity ratio of photovoltaic power generation unit is 100%, the relative installed capacity ratio of ground source heat pump unit is 20%, and the relative installed capacity ratio of absorption refrigeration unit 12 is 50%.

[0076] Scheduling strategies such as Figures 2 to 4 As shown: During the first peak electricity consumption period, the local consumption rate is 30% in summer, 5% in the transition season, and 35% in winter; during the trough electricity consumption period, the local consumption rate is 60% in summer, 10% in the transition season, and 60% in winter; during the second peak electricity consumption period, the local consumption rate is 30% in summer, 5% in the transition season, and 30% in winter.

[0077] Embodiment 2

[0078] A community of 1,000 households in Shanghai was selected as the energy supply object. The relative installed capacity ratio of biomass gasification cogeneration unit is 80%, the relative installed capacity ratio of biomass biogas power generation unit is 20%, the relative installed capacity ratio of biomass direct combustion heating unit is 70%, the relative installed capacity ratio of wind power generation unit is 80%, the relative installed capacity ratio of photovoltaic power generation unit is 80%, the relative installed capacity ratio of ground source heat pump unit is 30%, and the relative installed capacity ratio of absorption refrigeration unit 12 is 100%.

[0079] Dispatching strategy: During the first peak electricity consumption period, the local consumption rate is 35% in summer, 6% in the transition season, and 40% in winter; during the low electricity consumption period, the local consumption rate is 65% in summer, 15% in the transition season, and 65% in winter; during the second peak electricity consumption period, the local consumption rate is 35% in summer, 7% in the transition season, and 35% in winter.

[0080] Embodiment 3

[0081] A community of 1,000 households in Jinan City, Shandong Province was selected as the energy supply object. The relative installed capacity ratio of biomass gasification cogeneration unit is 90%, the relative installed capacity ratio of biomass biogas power generation unit is 40%, the relative installed capacity ratio of biomass direct combustion heating unit is 75%, the relative installed capacity ratio of wind power generation unit is 50%, the relative installed capacity ratio of photovoltaic power generation unit is 60%, the relative installed capacity ratio of ground source heat pump unit is 50%, and the relative installed capacity ratio of absorption refrigeration unit 12 is 150%.

[0082] Dispatching strategy: During the first peak electricity consumption period, the local consumption rate is 38% in summer, 8% in the transition season, and 42% in winter; during the low electricity consumption period, the local consumption rate is 68% in summer, 18% in the transition season, and 68% in winter; during the second peak electricity consumption period, the local consumption rate is 38% in summer, 8% in the transition season, and 38% in winter.

[0083] Embodiment 4

[0084] A community of 1,000 households in Zhangjiakou City, Hebei Province was selected as the energy supply object. The relative installed capacity ratio of biomass gasification cogeneration unit is 100%, the relative installed capacity ratio of biomass biogas power generation unit is 50%, the relative installed capacity ratio of biomass direct combustion heating unit is 80%, the relative installed capacity ratio of wind power generation unit is 20%, the relative installed capacity ratio of photovoltaic power generation unit is 20%, the relative installed capacity ratio of ground source heat pump unit is 60%, and the relative installed capacity ratio of absorption refrigeration unit 12 is 200%.

[0085] Dispatching strategy: During the first peak electricity consumption period, the local consumption rate is 40% in summer, 10% in the transition season, and 45% in winter; during the low electricity consumption period, the local consumption rate is 70% in summer, 20% in the transition season, and 70% in winter; during the second peak electricity consumption period, the local consumption rate is 40% in summer, 10% in the transition season, and 40% in winter.

[0086] The system of the present invention couples four kinds of renewable energy sources, and meets the needs of users of a certain scale for electric load, heat load, cooling load and gas load through energy conversion, energy transmission and energy storage; the secondary energy generated by the system is mostly consumed by the user-side load, and a small amount of excess secondary energy is consumed locally through city grid coupling, so the local consumption rate of the system is low, and there is no situation of selling electricity across walls; the system makes full use of local renewable energy, has stable energy supply, reduces carbon emissions, avoids impact on large power grids, and has good economy.

[0087] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention; any technology not involved in the present invention can be realized by existing technologies.

Claims

1. A fully renewable energy multi-energy complementary coupling energy supply system based on biomass energy, characterized by: The system utilizes four renewable primary energy sources, namely, biomass energy, wind energy (1), solar energy (3), and geothermal energy (6), and meets the needs of users of a certain scale for electric load (17), heat load (15), cooling load (14), and gas load (13) through energy conversion, energy transmission, and energy storage. Among them, the wind energy (1) converts part of the local wind resources into electric energy through a wind turbine generator set (25) and then connects to an electric bus (21); part of the biogas biomass energy (2) is converted into electric energy through a biogas generator set (24) and then enters the electric bus (21), and the rest is sent to a gas bus (9); the solar energy (3) converts part of the local solar energy resources into electric energy through a photovoltaic generator set (23) and then connects to the electric bus (21); part of the gasified biomass energy (4) is converted into electric energy through a cogeneration unit (22) and then enters the electric bus (21), and the cogeneration unit (22) converts the gasified biomass energy (4) into electric energy according to the corresponding heat-electricity ratio. The heat generated by the direct combustion biomass energy (5) is sent to the heat bus (16) with water as the working fluid, and the rest is sent to the gas bus (9); the direct combustion biomass energy (5) uses the biomass direct combustion boiler (7) to obtain heat in the form of direct combustion heating and enters the heat bus (16) with water as the working fluid; the geothermal energy (6) is converted into heat in the form of a heat pump by a ground source heat pump (8) in winter and the heat is sent to the heat bus (16) with water as the working fluid, and the heat is converted into heat in the form of a heat pump by a ground source heat pump (8) in summer. The internal heat is introduced into the ground and the generated cold energy enters the cold busbar (10) with water as the working medium; the electric busbar (21) is connected to the electric storage unit (20), the local consumption interface (19) and the electric load (17); the hot busbar (16) is connected to the heat storage unit (18) and the heat load (15); the cold busbar (10) is connected to the cold storage unit (30) and the cold load (14); and the gas busbar (9) is connected to the gas storage unit (11) and the gas load (13); The objective function of the dispatch strategy optimization model of the all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy requires that the sum of the system's annual investment cost, annual operating cost, annual maintenance cost and annual carbon tax amount be minimized. The objective function of the dispatch strategy optimization model is: In formula (1), TAC is the total annual cost of the system, RMB; IC i is the annual investment cost of the i-th unit, yuan; MC i,m,h is the maintenance cost of the i-th unit at the h-th hour in the m-th month, RMB; OC i,m,h is the operating cost of the i-th unit at the h-th hour in the m-th month, RMB; CE i,m,h is the carbon tax paid by the i-th unit for carbon emissions at the h-th hour of the m-th month, RMB; i is the type of unit, i includes wind power generation unit, biomass biogas power generation unit, photovoltaic power generation unit, biomass gasification cogeneration unit, biomass direct-fired heating unit, ground source heat pump unit, power storage unit (20), heat storage unit (18), absorption refrigeration unit (12), cold storage unit (30) and gas storage unit (11); The constraints of the objective function of the scheduling strategy optimization model include power balance constraint, heat balance constraint, and cooling balance constraint, wherein the power balance constraint is shown in formula (6): In formula (6): EO BCHP,m,h It represents the power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power scheduling, kW; EO PV,m,h Indicates the power output of the photovoltaic power generation unit at the hth hour in the mth month during power scheduling, kW; EO WT,m,h It represents the power output of the wind power generation unit at the hth hour in the mth month during power dispatch, kW; EO BPG,m,h It represents the power output of the biomass gas power generation unit at the hth hour in the mth month during power scheduling, kW; EO SBT,m,h represents the amount of electricity output by the power storage unit (20) at the hth hour in the mth month during power dispatch, kW; UEL m,h Indicates the amount of electricity consumed by the user's electrical load (17) in the hth hour of the mth month, kW; EC GSHP,,m,h Indicates the power consumed by the ground source heat pump unit at the hth hour in the mth month, kW; EC CS,m,h represents the amount of electricity consumed by the cold storage unit (30) during the cold storage process at the hth hour in the mth month, kW; EC CSR,m,h represents the power consumption of the cold storage unit (30) during the cooling process at the hth hour in the mth month, kW; EC SBT,m,h represents the amount of electricity stored in the power storage unit (20) at the hth hour in the mth month, kW; The heat balance constraint is shown in formula (7): TO BCHP,m,h +HO GSHP,m,h +HO BDCH,m,h +HO HS,m,h =UHL m,h +HC AC,m,h +HC HS,m,h (7) In formula (7), HO BCHP,m,h Indicates the heat output of the biomass gasification cogeneration unit at the hth hour in the mth month during heat scheduling, kW; HO GSHP,m,h Indicates the heat output of the ground source heat pump unit at the hth hour in the mth month during heat scheduling, kW; HO BDCH,m,h Indicates the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; HO HS,m,h represents the heat output of the heat storage unit (18) at the hth hour in the mth month during heat scheduling, kW; UHL m,h Indicates the heat load on the user side (15) The heat consumed in the hth hour of the mth month during heat scheduling, kW; HC AC,m,h represents the heat consumed by the absorption refrigeration unit (12) at the hth hour in the mth month during heat scheduling, kW; HC HS,m,h represents the amount of heat stored in the heat storage unit (18) at the hth hour in the mth month during heat scheduling, kW; The cooling balance constraint is shown in formula (8): WHAT GSHP,m,h +CO AC,m,h +CO CS,m,h =UCL m,h +CC CS ,m,h (8) In formula (8), CO GSHP,m,h Indicates the cooling capacity output at the hth hour in the mth month during the cooling capacity scheduling of the ground source heat pump unit, kW; CO AC,m,h represents the cooling capacity output at the hth hour in the mth month during cooling capacity scheduling of the absorption refrigeration unit (12), kW; CO CS,m,h represents the cooling capacity output at the hth hour in the mth month during cooling capacity scheduling of the cooling storage unit (30), kW; UCL m,h Indicates the cooling load on the user side (14) The cooling capacity consumed in the hth hour of the mth month during cooling capacity scheduling, kW; CC CS,m,h Indicates the cold capacity stored in the cold storage unit (30) at the hth hour in the mth month during cold capacity scheduling, in kW.

2. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The biogas biomass energy (2) uses a fermentation tank (28) to obtain biomass raw gas in an anaerobic / aerobic fermentation manner, and then passes through a biogas biomass purification unit (26) to obtain clean biomass gas. A portion of the clean biomass gas is converted into electrical energy through a biogas generator set (24) and then enters an electrical bus (21), and the remaining portion of the clean biomass gas is sent to a gas bus (9).

3. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The gasified biomass energy (4) uses a biomass gasification furnace (29) to obtain biomass raw fuel gas in a gasification manner, and then passes through a gasified biomass purification unit (27) to obtain clean biomass fuel gas. A portion of the clean biomass fuel gas is converted into electrical energy through a cogeneration unit (22) and then enters an electrical bus (21). The cogeneration unit (22) generates heat according to a corresponding heat-to-electricity ratio and enters a heat bus (16) using water as a working fluid, and then the remaining portion of the clean biomass fuel gas is sent to a gas bus (9).

4. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The hot bus (16) is connected to the absorption refrigeration unit (12), and the absorption refrigeration unit (12) uses the heat of the hot bus to generate cold energy and transmits it to the cold bus (10).

5. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: Annual investment cost IC of the i-th unit i The annualized value is obtained by multiplying the rated capacity of the i-th unit by the kilowatt cost of the i-th unit, as shown in formula (2): In formula (2), IC i is the annual investment cost of the i-th unit; g is the annual interest rate of capital investment; y is the useful life of the equipment; RC i is the capacity configuration of the i-th unit, kW; UP i is the kilowatt cost of the i-th unit investment, yuan / kW.

6. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The annual operating cost OC of the i-th unit i It is determined by the raw materials consumed and the price of raw materials during the output process when the i-th unit participates in the system energy scheduling, as shown in formula (3): In formula (3), OC i represents the annual operating cost of the i-th unit; EO BCHP,m,h The power output of the biomass gasification cogeneration unit at the hth hour in the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass gasification cogeneration unit; CV BRM is the calorific value of biomass raw materials, kJ / kg; P BRM，m is the unit price of biomass raw materials, yuan / kg; EO BPG,m,h The power output of the biomass gas power generation unit in the hth hour of the mth month during power dispatch, kW; is the electricity conversion efficiency of the biomass biogas power generation unit; CV KW is the calorific value of kitchen waste, kJ / kg; P KW,m The subsidy price for the collection, transportation and treatment of restaurant kitchen waste is RMB / kg; HO BDCH,m,h is the heat output of the biomass direct-fired heating unit at the hth hour in the mth month during heat scheduling, kW; is the heat conversion efficiency of the biomass direct-fired heating unit; CV BRM is the calorific value of biomass raw material, kJ / kg;.

7. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The annual maintenance cost MC of the i-th unit i It is determined by the output size and unit maintenance cost of the i-th unit when it participates in system energy dispatch, as shown in formula (4): In formula (4), MC i is the annual maintenance cost of the i-th unit; EO i,m,h is the power output of the i-th unit at the h-th hour in the m-th month during power scheduling, kW; HO i,m,h is the heat output of the i-th unit in the m-th month and the h-th hour during heat scheduling; CO i,m,h P is the cooling capacity output by the i-th unit in the h-th hour of the m-th month during cooling capacity scheduling, kW; i is the unit maintenance cost when the i-th unit participates in scheduling, RMB / kW.

8. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: The annual carbon tax amount CE of the i-th unit i It is determined by the carbon dioxide emissions and unit carbon tax when the i-th unit participates in system energy scheduling, as shown in formula (5): In formula (5), CE i is the annual carbon tax amount of the i-th unit; α i is the carbon dioxide emission conversion coefficient of the ith unit when participating in power dispatch, kg / kW; β i is the carbon dioxide emission conversion coefficient of the ith unit when participating in heat dispatch output, kg / kW; δ i is the carbon dioxide emission conversion coefficient when the i-th unit participates in cooling capacity scheduling, kg / kW; η is the carbon dioxide emission tax, yuan / kg.

9. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: Based on the objective function of the scheduling strategy optimization model, the relative installed capacity ratio of the biomass biogas power generation unit is 10% to 50%, the relative installed capacity ratio of the biomass gasification cogeneration unit is 60% to 100%, and the relative installed capacity ratio of the biomass direct-fired heating unit is 60% to 80%; the relative installed capacity ratio of the wind power generation unit is 20% to 100%, the relative installed capacity ratio of the photovoltaic power generation unit is 20% to 100%, the relative installed capacity ratio of the ground source heat pump unit is 20% to 60%, and the relative installed capacity ratio of the absorption refrigeration unit (12) is 50% to 200%.

10. The all-renewable energy multi-energy complementary coupling energy supply system based on biomass energy according to claim 1 is characterized by: Based on the objective function of the dispatch strategy optimization model, the local consumption rates of the local consumption interface (19) in the first peak period, the valley period and the second peak period are as follows: in the first peak period, the local consumption rate in summer is 30% to 40%, the local consumption rate in the transition season is 5% to 10%, and the local consumption rate in winter is 35% to 45%; in the valley period, the local consumption rate in summer is 60% to 70%, the local consumption rate in the transition season is 10% to 20%, and the local consumption rate in winter is 60% to 70%; During the second peak electricity consumption period, the local consumption rate is 30% to 40% in summer, 5% to 10% in the transition season, and 30% to 40% in winter.

Images