Cooperative optimization scheduling method for electricity-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy

Abstract

The present invention provides a method for collaborative optimization and scheduling of an electric-hydrogen system using a magnesium-based transporter to transport hydrogen energy, comprising the following steps: constructing a magnesium-based transporter loading and unloading hydrogen energy operation model; constructing an electric-hydrogen system collaborative optimization scheduling objective function; constructing an electric-hydrogen system collaborative optimization scheduling constraint condition, including a hydrogen plant operation constraint, an MTV hydrogen transportation constraint, a hydrogen station operation constraint, and a power system operation constraint; considering the uncertainty of wind energy, using information gap decision theory, constructing an electric-hydrogen system collaborative optimization scheduling model for transporting hydrogen energy using a magnesium-based transporter; solving the scheduling model for different deviation factors, and solving the electric-hydrogen system collaborative optimization scheduling model for transporting hydrogen energy using a magnesium-based transporter according to the objective function and the constraint condition, using a mathematical programming model solver, to minimize the system operation cost. Under the premise of ensuring the safe operation of the electric-hydrogen system, the method transports hydrogen energy from the hydrogen plant to each hydrogen station in a solid state, reduces the operating cost of the system, and reduces the safety hazards of hydrogen energy transportation.

Description

Technical Field

[0001] The present invention relates to the field of low-carbon operation of electric power systems, and in particular to a coordinated optimization scheduling method for an electric-hydrogen system that utilizes a magnesium-based transport vehicle to transport hydrogen energy. Background Art

[0002] In the context of global fossil energy shortage, hydrogen energy, as a high-quality clean energy, has the advantages of large-scale transportation and long-term storage in addition to low carbon and environmental protection. It is widely used in transportation, industry, production and energy storage. At present, the rapid growth of renewable energy installed capacity makes it difficult for the electric power system (EPS) to adapt to such a high degree of renewable energy penetration. The excess electricity generated by renewable energy is converted into hydrogen energy through electrolysis technology. Therefore, building an electricity-hydrogen energy system (EHS) consisting of an electric power system and a hydrogen energy system (HES) is an important direction for the development of the future power system.

[0003] The electric-hydrogen system needs to consider the transportation of hydrogen energy. Hydrogen energy transportation is different from electric energy transmission. In the existing technology, hydrogen energy is often transported in gaseous form through MTV. However, gaseous hydrogen energy has a low hydrogen storage density and needs to be compressed before transportation to consume energy. During transportation, hydrogen leakage and flammability and explosion are prone to safety problems. The pressure resistance requirements for hydrogen storage containers are high, resulting in high transportation costs and poor safety. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a coordinated optimization scheduling method for an electric-hydrogen system that uses a magnesium-based transport vehicle to transport hydrogen energy. Under the premise of ensuring the safe operation of EHS, hydrogen energy is transported from a hydrogen production plant to various hydrogen refueling stations in a solid form, thereby reducing the operating cost of the system and reducing the safety hazards of hydrogen energy transportation.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a coordinated optimization scheduling method of an electric-hydrogen system for transporting hydrogen energy using a magnesium-based transport vehicle, comprising the following steps:

[0006] S1. Construct a hydrogen energy operation model for magnesium-based transport vehicles;

[0007] S2. Construct the objective function of coordinated optimization scheduling of the electricity-hydrogen system;

[0008] S3. Construct the coordinated optimization scheduling constraints of the electricity-hydrogen system, including the operation constraints of the hydrogen production plant, the MTV hydrogen transportation constraints, the operation constraints of the hydrogen refueling station and the operation constraints of the power system;

[0009] S4. Considering the uncertainty of wind energy, using information gap decision theory, a coordinated optimization scheduling model for the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is constructed;

[0010] S5. Solve the scheduling model for different deviation factors. According to the objective function and constraints, use the mathematical programming model solver to solve the coordinated optimization scheduling model of the electric-hydrogen system that uses magnesium-based transport vehicles to transport hydrogen energy, so as to minimize the system operation cost.

[0011] In a preferred solution, in step S1, the magnesium-based transport vehicle loading and unloading hydrogen energy operation model includes MTV hydrogen loading constraints, MTV hydrogen transportation constraints and MTV hydrogen unloading constraints;

[0012] 1) The MTV hydrogen loading constraint expression is as follows:

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020] The above formula represents the MTV hydrogen filling process, where p a is the pressure in the system when magnesium absorbs hydrogen; p pr is the equilibrium pressure when magnesium absorbs hydrogen; E a is the activation energy of hydrogen absorption; ΔH a is the heat of hydrogen absorption reaction; ΔS a is the entropy of hydrogen absorption reaction; T a is the steady-state temperature when magnesium absorbs hydrogen; R g is the ideal gas constant; p 0 is the atmospheric pressure; is the rate at which the hydrogen production plant absorbs hydrogen during period t; mo mgh is the molar mass of magnesium hydride; is the mass of metallic magnesium in the hydrogen production plant h during period t; is the mass of magnesium hydride in the hydrogen production plant h during period t; S C K is the chemical reaction stoichiometry; a is the pre-exponential factor for hydrogen absorption; is the maximum hydrogen absorption of the hydrogen production plant h in period t; ΔT is the time interval; is the amount of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the total mass of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the mass of hydrogen in the hydrogen production plant h during period t; mo h is the molar mass of hydrogen; wt% is the hydrogen storage percentage of magnesium hydride; The total hydrogen loaded to the MTV by the hydrogen production plant; The hydrogen produced by the hydrogen production plant h in time period t is directly loaded into the MTV; is the hydrogen loaded to MTV by hydrogen production plant h during period t;

[0021] 2) The expression of MTV hydrogen transport constraint is as follows:

[0022]

[0023]

[0024]

[0025] N a -1≥N a ·u r,r',c +X r,c -X r',c (11)

[0026] The above formula represents the route selection when MTV transports hydrogen. h Indicates the number of hydrogen production plants; N r Indicates the number of hydrogen refueling stations; N h' is a virtual node, indicating the number of hydrogen production plants returned after the MTV transportation is completed; u r,r',c Indicates whether there is a c-th MTV transporting magnesium hydride from r to r', N a is the number of all hydrogen production plants and hydrogen refueling stations included in the MTV driving loop, X r,c and X r',c is the introduced auxiliary variable.

[0027]

[0028]

[0029]

[0030] The above formula represents the time required for MTV to transport hydrogen, where: is the time when the cth MTV arrives at location r; is the travel time of the cth MTV from r to r'; The time required to unload magnesium hydride; is a 0 / 1 variable, indicating whether the cth MTV unloads magnesium hydride at r; d r,r' is the distance between r and r'; v r,r',c is the speed of the cth MTV between r and r'; is the earliest time that the cth MTV arrives at location r; is the latest time for the cth MTV to arrive at location r, M is a sufficiently large number; is the time when the cth MTV arrives at r'.

[0031] 3) The expression of MTV hydrogen unloading constraint is as follows:

[0032]

[0033]

[0034]

[0035]

[0036] The above formula represents the hydrogen energy balance during the MTV hydrogen unloading process, where N b The time set for MTV to arrive at the hydrogen refueling station; is the total hydrogen transported from MTV to location r during period t; The hydrogen transported to the rth place by the cth MTV; is the amount of hydrogen at hydrogen filling station r during period t; is the total mass of hydrogen in magnesium hydride at hydrogenation station r during period t; is the hydrogen content in the cth MTV when it leaves r; is the hydrogen content in the cth MTV when leaving r'; The hydrogen transported to r' by the cth MTV; is the minimum hydrogen content in the cth MTV when leaving r place; is the maximum hydrogen content in the cth MTV when leaving r;

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043] The above formula represents the MTV hydrogen unloading process, where p ref is the equilibrium pressure when magnesium hydride releases hydrogen; ΔH re is the heat of hydrogen release reaction; T r Steady-state temperature when magnesium hydride releases hydrogen; E re is the activation energy of hydrogen release; ΔS re is the entropy of hydrogen release reaction; K is the rate at which hydrogen is released by hydrogen refueling station r during period t; re is the pre-exponential factor of hydrogen release; p re is the pressure in the system when magnesium hydride releases hydrogen; is the mass of magnesium hydride in hydrogenation station r during period t; is the maximum hydrogen discharge capacity of hydrogen refueling station r during period t; is the amount of hydrogen released from magnesium hydride in hydrogenation station r during period t; is the amount of hydrogen released from magnesium hydride in hydrogenation station r during period t.

[0044] In a preferred solution, in step S2, the construction of the electricity-hydrogen system collaborative optimization scheduling objective function is as follows:

[0045] The objective function of the coordinated optimization scheduling of the electricity-hydrogen system aims to minimize the operating cost F, which mainly includes the EPS operating cost and the MTV transportation cost. Its expression is as follows:

[0046] minF=F EPS +F TRA (25)

[0047] In the formula, F EPS is the EPS operating cost; F TRA The cost of transporting hydrogen for MTV;

[0048] The EPS operating cost F EPS The expression is:

[0049]

[0050] In the formula, and They are the startup cost and shutdown cost of thermal power units respectively; is the no-load cost of thermal power units; is the operating cost of thermal power units; and is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; v i,t It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; N g It is the collection of thermal power units in the system;

[0051] The MTV transportation cost F TRA The expression is:

[0052]

[0053] In the formula, is the fixed transportation cost of the cth MTV, is the driving cost of the cth MTV in period t, η r,r' is the distance between r and r'. c It is a collection of MTV numbers.

[0054] In a preferred solution, in step S3, the expression of the scheduling constraint condition of the electricity-hydrogen system collaborative optimization is as follows:

[0055] 1) Hydrogen plant operation constraints:

[0056]

[0057]

[0058]

[0059]

[0060] The above formula represents the power consumed by the hydrogen production plant and the output of hydrogen; where, is the total power consumed by the hydrogen plant h during period t; is the power consumed by the hydrogen plant for compression and purification of hydrogen in period t; K is the power consumed by the hydrogen production plant in time period t h; c The compression factor for hydrogen purification; K is the hydrogen produced by the hydrogen production plant h during period t; pr is the hydrogen production coefficient;

[0061]

[0062]

[0063]

[0064]

[0065]

[0066] The above formula represents the hydrogen energy balance in the hydrogen production plant, where: is the hydrogen produced by the hydrogen production plant h during period t; is the mass of hydrogen in the hydrogen production plant h during period t; is the total mass of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; The hydrogen produced by the hydrogen production plant h in time period t is directly loaded into the MTV; The hydrogen produced by the hydrogen production plant h in time period t is the hydrogen stored in the hydrogen production plant itself; is the hydrogen loaded to MTV by hydrogen production plant h during period t; is the hydrogen stored in the hydrogen production plant h during period t; is the minimum amount of hydrogen produced by the hydrogen production plant h during period t; is the maximum amount of hydrogen produced by the hydrogen plant h during period t; is the minimum amount of hydrogen that can be stored in the hydrogen production plant h during time period t; is the maximum amount of hydrogen that can be stored in hydrogen production plant h during time period t;

[0067] 2) Hydrogen station operation constraints:

[0068]

[0069]

[0070]

[0071] The above formula represents the hydrogen energy balance in the hydrogen refueling station, where: The hydrogen stored at hydrogen refueling station r during time period t; is the total hydrogen transported from MTV to location r during period t; is the hydrogen load consumed by hydrogen refueling station r during period t; is the total amount of hydrogen transported from MTV to location r at least during period t; is the total amount of hydrogen transported from MTV to location r at most during period t; The minimum amount of hydrogen stored at hydrogen refueling station r during time period t; The maximum amount of hydrogen stored at hydrogen refueling station r during time period t.

[0072] 3) The constraints of MTV hydrogen transportation are the same as those of the magnesium-based transport vehicle loading and unloading hydrogen energy operation model in step S1;

[0073] 4) EPS operation constraints:

[0074] Start and stop of thermal power units:

[0075]

[0076] Thermal power unit operation / stop time:

[0077]

[0078]

[0079] Thermal power unit power upper and lower limits:

[0080]

[0081] Thermal power unit climbing constraints:

[0082]

[0083]

[0084] Power balance within the system:

[0085]

[0086] In the formula, and is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; v i,t It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; T i on and T i off are the time required for starting and shutting down the i-th conventional unit respectively; P i g,min and P i g,max are the minimum output and maximum output of the i-th conventional unit respectively; and are the upward and downward climbing rates of the i-th conventional unit respectively; N g is the set of thermal power units in the system; N w is the set of wind turbines in the system; N d is the set of load nodes in the system; N h Indicates the number of hydrogen production plants; is the wind turbine power during period t; is the load output during period t.

[0087] In a preferred solution, in step S4, the coordinated optimization scheduling model of the electric-hydrogen system for transporting hydrogen energy using a magnesium-based transport vehicle is as follows:

[0088] When the decision maker selects the IGDT opportunity model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows:

[0089]

[0090] In the formula, δ o is the fluctuation range of the uncertain variable in the chance model; σ o is the chance deviation factor; F0 is the optimal result under the deterministic problem; is the predicted value of wind power output; δ wis the uncertain parameter of wind power output; F(x,μ) represents the cost function of the model; J(x,μ)=0 represents the equality constraint; K(x,μ)≥0 represents the inequality constraint.

[0091] When the decision maker selects the IGDT robust model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows:

[0092]

[0093] In the formula, δ r is the fluctuation range of the uncertain variables of the robust model; σ r is the robust deviation factor;

[0094] In the preferred solution, in step S4, the wind power output uncertainty set The expression is as follows:

[0095]

[0096] The present invention provides a coordinated optimization scheduling method for an electric-hydrogen system using a magnesium-based transport vehicle to transport hydrogen energy, which has the following beneficial effects:

[0097] 1. In step S1, a model for loading and unloading hydrogen energy by a magnesium-based transport vehicle is constructed, hydrogen is converted into solid magnesium hydride for storage and transportation by chemical reaction, and the MTV operation route is optimized to reduce transportation costs in view of the complex traffic problems in hydrogen energy transportation.

[0098] 2. In step S3, the coordinated optimization dispatching constraints of the electricity-hydrogen system are constructed to achieve the coordinated optimization operation between the power system and the hydrogen energy system.

[0099] 3. In step S4, the uncertainty of wind energy in the electric-hydrogen system is considered through the information gap decision theory, and analysis is performed from the perspectives of opportunity seeking strategy and risk avoidance strategy to simultaneously consider the economy and robustness of the electric-hydrogen system.

[0100] 4. The method proposed in the present invention can realize the coordinated operation of the power system and the hydrogen energy system under renewable energy (wind energy). After considering the operation model of magnesium-based transport vehicles loading and unloading hydrogen energy, the present invention converts hydrogen into solid hydrogen energy storage and transportation through chemical reactions, so that each MTV can load more hydrogen energy compared with traditional long-tube trailers, thereby improving the problems of low hydrogen storage capacity, flammability and easy leakage when traditional long-tube trailers transport high-pressure hydrogen. Therefore, the present invention not only has lower transportation costs, but also allows decision makers to make decisions based on safety and robustness by considering the uncertainty of wind energy, thereby realizing the coordinated optimization and scheduling of the electric-hydrogen system.

[0101] 5. Compared with the existing technology, hydrogen energy is converted from hydrogen to magnesium hydride for storage through the gas-solid conversion of hydrogen energy, and transported from the hydrogen production plant to various hydrogen refueling stations through MTV. At the hydrogen refueling station, magnesium hydride is decomposed into hydrogen storage through the solid-gas conversion of hydrogen energy for use by hydrogen load, thereby reducing the operating cost of EHS and improving system safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0102] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0103] Figure 1 It is a flow chart of the present invention.

[0104] Figure 2 The hydrogen load demand of the hydrogen refueling station in the EHS;

[0105] Figure 3 It is the wind power output prediction curve of the two wind farms in EHS;

[0106] Figure 4 Transporting time and space diagrams for MTV;

[0107] Figure 5 Comparison of IGDT costs under different uncertain parameters. DETAILED DESCRIPTION

[0108] Combination Figure 1 to Figure 5 The specific embodiments of the present invention are described in further detail.

[0109] A coordinated optimization scheduling method for an electricity-hydrogen system using a magnesium-based transport vehicle to transport hydrogen energy, such as Figure 1 As shown, the following steps are included:

[0110] S1. Construct a model for the operation of magnesium-based transport vehicle loading and unloading hydrogen. MTV stands for Magnesium based transport vehicle (MTV)

[0111] The hydrogen loading and unloading energy operation model of magnesium-based transport vehicles includes MTV hydrogen loading constraints, MTV hydrogen transportation constraints and MTV hydrogen unloading constraints.

[0112] 1) The MTV hydrogen loading constraint expression is as follows:

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120] The above formula represents the MTV hydrogen loading process, where hydrogen and magnesium react to generate magnesium hydride for solid-state storage and then loaded into the MTV.

[0121] In the formula, p a is the pressure in the system when magnesium absorbs hydrogen; p pr is the equilibrium pressure when magnesium absorbs hydrogen; E a is the activation energy of hydrogen absorption; ΔH a is the heat of hydrogen absorption reaction; ΔS a is the entropy of hydrogen absorption reaction; T a is the steady-state temperature when magnesium absorbs hydrogen; R g is the ideal gas constant; p 0 is the atmospheric pressure; is the rate at which the hydrogen production plant absorbs hydrogen during period t; mo mgh is the molar mass of magnesium hydride; is the mass of metallic magnesium in the hydrogen production plant h during period t; is the mass of magnesium hydride in the hydrogen production plant h during period t; S C K is the chemical reaction stoichiometry; a is the pre-exponential factor for hydrogen absorption; is the maximum hydrogen absorption of the hydrogen production plant h in period t; ΔT is the time interval; is the amount of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the total mass of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the mass of hydrogen in the hydrogen production plant h during period t; mo h is the molar mass of hydrogen; wt% is the hydrogen storage percentage of magnesium hydride; The total hydrogen loaded to the MTV by the hydrogen production plant; The hydrogen produced by the hydrogen production plant h in time period t is directly loaded into the MTV; The hydrogen loaded to MTV by hydrogen plant h during period t.

[0122] 2) The expression of MTV hydrogen transport constraint is as follows:

[0123]

[0124]

[0125]

[0126] N a -1≥N a ·u r,r',c+X r,c -X r',c (11)

[0127] The above formula represents the route selection when MTV transports hydrogen.

[0128] Where N h Indicates the number of hydrogen production plants; N r Indicates the number of hydrogen refueling stations; N h' is a virtual node, indicating the number of hydrogen production plants returned after the MTV transportation is completed; u r,r',c Indicates whether there is a c-th MTV transporting magnesium hydride from r to r', N a is the number of all hydrogen production plants and hydrogen refueling stations included in the MTV driving loop, X r,c and X r',c is the introduced auxiliary variable.

[0129]

[0130]

[0131]

[0132] The above formula represents the time required for MTV to transport hydrogen.

[0133] In the formula, is the time when the cth MTV arrives at location r; is the travel time of the cth MTV from r to r'; T r rel The time required to unload magnesium hydride; is a 0 / 1 variable, indicating whether the cth MTV unloads magnesium hydride at r; d r,r' is the distance between r and r'; v r,r',c is the speed of the cth MTV between r and r'; is the earliest time that the cth MTV arrives at location r; is the latest time for the cth MTV to arrive at location r, and M is a sufficiently large number. is the time when the cth MTV arrives at r'.

[0134] 3) The expression of MTV hydrogen unloading constraint is as follows:

[0135]

[0136]

[0137]

[0138]

[0139] The above formula represents the hydrogen energy balance during the MTV hydrogen unloading process.

[0140] Where N b The time set for MTV to arrive at the hydrogen refueling station; is the total hydrogen transported from MTV to location r during period t; The hydrogen transported to the rth location by the cth MTV; is the amount of hydrogen at hydrogen filling station r during period t; is the total mass of hydrogen in magnesium hydride at hydrogenation station r during period t; is the hydrogen content in the cth MTV when it leaves r; is the hydrogen content in the cth MTV when leaving r'; The hydrogen transported to r' by the cth MTV; is the minimum hydrogen content in the cth MTV when leaving r place; is the maximum hydrogen content in the cth MTV when leaving r.

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147] The above formula represents the MTV hydrogen unloading process, where magnesium hydride decomposes into gaseous hydrogen and is stored in a hydrogen refueling station for use by hydrogen fuel cell electric vehicles.

[0148] In the formula, p ref is the equilibrium pressure when magnesium hydride releases hydrogen; ΔH re is the heat of hydrogen release reaction; T r is the steady-state temperature when magnesium hydride releases hydrogen; E re is the activation energy of hydrogen release; ΔS re is the entropy of hydrogen release reaction; K is the rate at which hydrogen is released by hydrogen refueling station r during period t; re is the pre-exponential factor of hydrogen release; p re is the pressure in the system when magnesium hydride releases hydrogen; is the mass of magnesium hydride in hydrogenation station r during period t; is the maximum hydrogen discharge capacity of hydrogen refueling station r during period t; is the amount of substance when magnesium hydride releases hydrogen in hydrogenation station r during time period t. is the amount of hydrogen released from magnesium hydride in hydrogenation station r during period t.

[0149] S2. Construct an objective function for the coordinated optimization and dispatching of the electricity-hydrogen system. This objective function improves the utilization rate of hydrogen energy by using magnesium-based transport vehicles to transport hydrogen energy, reduces the system operating costs, and improves the safety of hydrogen energy transportation.

[0150] The construction of the objective function of the coordinated optimization scheduling of the electricity-hydrogen system is as follows:

[0151] The objective function of the coordinated optimization scheduling of the electricity-hydrogen system aims to minimize the operating cost F, which mainly includes the EPS operating cost and the MTV transportation cost. Its expression is as follows:

[0152] minF=F EPS +F TRA (25)

[0153] In the formula, F EPS is the EPS operating cost; F TRA The cost of transporting hydrogen to MTV.

[0154] The EPS operating cost F EPS The expression is:

[0155]

[0156] In the formula, and They are the startup cost and shutdown cost of thermal power units respectively; is the no-load cost of thermal power units; is the operating cost of thermal power units; and is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; v i,t It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; N g It is the collection of thermal power units in the system.

[0157] The MTV transportation cost F TRA The expression is:

[0158]

[0159] In the formula, is the fixed transportation cost of the cth MTV, is the driving cost of the cth MTV in period t, η r,r' is the distance between r and r'. c It is a collection of MTV numbers.

[0160] S3. Construct the coordinated optimization scheduling constraints of the electricity-hydrogen system, including the operation constraints of the hydrogen production plant, the MTV hydrogen transportation constraints, the operation constraints of the hydrogen refueling station and the electric power system (EPS).

[0161] The expression of the constraints for the coordinated optimization of the electricity-hydrogen system scheduling is as follows:

[0162] 1) Hydrogen plant operation constraints:

[0163]

[0164]

[0165]

[0166]

[0167] The above formula represents the power consumed by the hydrogen production plant and the hydrogen output.

[0168] In the formula, is the total power consumed by the hydrogen plant h during period t; is the power consumed by the hydrogen plant for compression and purification of hydrogen in period t; K is the power consumed by the hydrogen production plant in time period t h; c The compression factor for hydrogen purification; K is the hydrogen produced by the hydrogen production plant h during period t; pr is the hydrogen production coefficient;

[0169]

[0170]

[0171]

[0172]

[0173]

[0174] The above formula represents the hydrogen energy balance within the hydrogen production plant.

[0175] In the formula, is the hydrogen produced by the hydrogen production plant h during period t; is the mass of hydrogen in the hydrogen production plant h during period t; is the total mass of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; The hydrogen produced by the hydrogen production plant h in time period t is directly loaded into the MTV; The hydrogen produced by the hydrogen production plant h in time period t is the hydrogen stored in the hydrogen production plant itself; is the hydrogen loaded to MTV by hydrogen production plant h during period t; is the hydrogen stored in the hydrogen production plant h during period t; is the minimum amount of hydrogen produced by the hydrogen production plant h during period t; is the maximum amount of hydrogen produced by the hydrogen plant h during period t; is the minimum amount of hydrogen that can be stored in the hydrogen production plant h during time period t; The maximum amount of hydrogen that can be stored in hydrogen production plant h during time period t.

[0176] 2) Hydrogen station operation constraints:

[0177]

[0178]

[0179]

[0180] The above formula represents the hydrogen energy balance in the hydrogen refueling station.

[0181] In the formula, The hydrogen stored at hydrogen refueling station r during time period t; is the total hydrogen transported from MTV to location r during period t; is the hydrogen load consumed by hydrogen refueling station r during period t; is the total amount of hydrogen transported from MTV to location r at least during period t; is the total amount of hydrogen transported from MTV to location r at most during period t; The minimum amount of hydrogen stored at hydrogen refueling station r during time period t; The maximum amount of hydrogen stored at hydrogen refueling station r during time period t.

[0182] 3) The MTV hydrogen transportation constraints are the same as the constraints of the magnesium-based transport vehicle loading and unloading hydrogen energy operation model in step S1, see equations (1) to (24) for details.

[0183] 4) EPS operation constraints:

[0184] Start and stop of thermal power units:

[0185]

[0186] Thermal power unit operation / stop time:

[0187]

[0188]

[0189] Thermal power unit power upper and lower limits:

[0190]

[0191] Thermal power unit climbing constraints:

[0192]

[0193]

[0194] Power balance within the system:

[0195]

[0196] The above formula represents the EPS operation constraints.

[0197] In the formula, and is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; v i,t It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; T i on and T i off are the time required for starting and shutting down the i-th conventional unit respectively; P i g,min and P i g,max are the minimum output and maximum output of the i-th conventional unit respectively; and are the upward and downward climbing rates of the i-th conventional unit respectively; N g is the set of thermal power units in the system; N w is the set of wind turbines in the system; N d is the set of load nodes in the system; N h Indicates the number of hydrogen production plants; is the wind turbine power during period t; is the load output during period t.

[0198] S4. Considering the uncertainty of wind energy, the information-gap decision theory (IGDT) is used to construct a collaborative optimization scheduling model for the electric-hydrogen system that uses magnesium-based transport vehicles to transport hydrogen energy.

[0199] The coordinated optimization scheduling model of the electricity-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows:

[0200] When the decision maker selects the IGDT opportunity model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows:

[0201]

[0202] In the formula, δ ois the fluctuation range of the uncertain variable in the chance model; o is the chance deviation factor; F0 is the optimal result under the deterministic problem; is the predicted value of wind power output; δ w is the uncertain parameter of wind power output; F(x,μ) represents the cost function of the model; J(x,μ)=0 represents the equality constraint; K(x,μ)≥0 represents the inequality constraint.

[0203] When the decision maker selects the IGDT robust model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows:

[0204]

[0205] In the formula, δ r is the fluctuation range of the uncertain variables of the robust model; σ r is the robust deviation factor;

[0206] Wind power output uncertainty set The expression is as follows:

[0207]

[0208] S5. Solve the scheduling model for different deviation factors. According to the objective function and constraints, use the mathematical programming model solver GUROBI to solve the collaborative optimization scheduling model of the electric-hydrogen system that uses magnesium-based transport vehicles to transport hydrogen energy, so as to minimize the system operation cost.

[0209] The proposed method was tested on an improved IEEE-118 node test system, including 54 thermal power units, 2 wind farms, 2 hydrogen production plants and 10 hydrogen refueling stations.

[0210] Figure 2 The hydrogen load demand of hydrogen refueling stations within EHS is 9,313 kg of hydrogen per day for 10 hydrogen refueling stations.

[0211] Figure 3 It is the wind power output prediction curve of the two wind farms in EHS, indicating the predicted value of wind power output.

[0212] Figure 4 This is the MTV transportation time-space diagram. After optimized scheduling, EHS needs a total of 10 MTVs to supply hydrogen to the hydrogen refueling station. They will arrive at the hydrogen refueling station one after another starting from 10:00 and complete the transportation at 20:00.

[0213] Figure 5To compare the IGDT costs under different uncertain parameters, the difference between the benchmark cost and the IGDT model cost is defined as the IGDT cost. As the uncertain parameters of wind power increase, the greater the IGDT cost of the IGDT opportunity model, the more additional benefits the EHS obtains; the smaller the IGDT cost of the IGDT robust model, the more additional losses the EHS obtains.

[0214] Table 1 compares the relationship between the cost and the number of MTVs at different MTV hydrogen loadings (the mass of hydrogen in magnesium hydride) under the opportunity model and the robust model. The total amount of hydrogen loaded by the MTV is related to the hydrogen load consumption of the hydrogen filling station. The fixed transportation cost of each MHTV is 600 yuan, including the rental fee of the MTV and the driver's salary. As the amount of hydrogen loaded by the MTV increases, the number of MTVs required for transportation is smaller, and the fixed cost is lower. In addition, the fewer the number of MTVs, the shorter the total distance of MTV transportation, which effectively reduces the hydrogen transportation cost of MTVs. Since the opportunity model is more radical than the robust model, it is expected that the uncertainty of wind power will develop in a favorable direction, reducing the output of conventional units, thereby reducing EPS costs; the robust strategy model is more conservative than the opportunity model, with less wind power output in the electric-hydrogen system, and more conventional units are allowed to output to cope with uncertainty, and it is expected that the uncertainty of wind power output will develop in a worse direction, resulting in higher EPS costs.

[0215] Table 1 Cost analysis of different MTV hydrogen loading amounts

[0216]

Claims

1. A coordinated optimization scheduling method for an electric-hydrogen system using a magnesium-based transport vehicle to transport hydrogen energy, characterized in that: The steps include: S1. Construct a hydrogen energy operation model for magnesium-based transport vehicles; The operation model of magnesium-based transport vehicle loading and unloading hydrogen includes MTV hydrogen loading constraint, MTV hydrogen transportation constraint and MTV hydrogen unloading constraint; 1) The MTV hydrogen loading constraint expression is as follows: (1)； (2)； (3)； (4)； (5)； (6)； (7)； The above formula represents the MTV hydrogen filling process, where: is the pressure in the system when magnesium absorbs hydrogen; is the equilibrium pressure when magnesium absorbs hydrogen; is the activation energy of hydrogen absorption; The heat of hydrogen absorption reaction; is the entropy of hydrogen absorption reaction; is the steady-state temperature when magnesium absorbs hydrogen; is the ideal gas constant; is the atmospheric pressure; is the rate at which the hydrogen production plant absorbs hydrogen during time period t; is the molar mass of magnesium hydride; is the mass of metallic magnesium in the hydrogen production plant h during period t; is the mass of magnesium hydride in the hydrogen production plant h during period t; is the chemical reaction stoichiometry; is the pre-exponential factor for hydrogen uptake; is the maximum hydrogen absorption of the hydrogen production plant h in period t; is the time interval; is the amount of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the total mass of hydrogen in magnesium hydride in the hydrogen production plant h during time period t; is the mass of hydrogen in the hydrogen production plant h during period t; is the molar mass of hydrogen; is the hydrogen storage percentage of magnesium hydride; The total hydrogen loaded to the MTV by the hydrogen production plant; The hydrogen produced by the hydrogen production plant h in time period t is directly loaded into the MTV; is the hydrogen loaded to MTV by hydrogen production plant h during period t; 2) The expression of MTV hydrogen transport constraint is as follows: (8)； (9)； (10)； (11)； The above formula represents the route selection when MTV transports hydrogen, where: Indicates the number of hydrogen production plants; Indicates the number of hydrogen refueling stations; It is represented as a virtual node, indicating the number of hydrogen plants returned after the MTV transportation is completed; Indicates whether there is a cth MTV that transfers magnesium hydride from r Transport to land, is the number of all hydrogen production plants and hydrogen refueling stations included in the MTV driving loop, and is the auxiliary variable introduced; (12)； (13)； (14)； The above formula represents the time required for MTV to transport hydrogen, where: is the time when the cth MTV arrives at location r; For the cth MTV from r to The driving time of the land; The time required to unload magnesium hydride; is a 0 / 1 variable, indicating whether the cth MTV unloads magnesium hydride at location r; For r and The distance between the lands; For the cth MTV in r place and The speed of travel between the grounds; is the earliest time that the cth MTV arrives at location r; is the latest time for the cth MTV to arrive at location r, M is a sufficiently large number; is the time when the cth MTV arrives at r'; 3) The expression of MTV hydrogen unloading constraint is as follows: (15)； (16)； (17)； (18)； The above formula represents the hydrogen energy balance during the MTV hydrogen unloading process, where: The time set for MTV to arrive at the hydrogen refueling station; is the total hydrogen transported from MTV to location r during period t; The hydrogen transported to the rth location by the cth MTV; is the amount of hydrogen at hydrogen filling station r during period t; is the total mass of hydrogen in magnesium hydride at hydrogenation station r during period t; is the hydrogen content in the cth MTV when it leaves r; is the hydrogen content in the cth MTV when leaving r'; The hydrogen transported to r' by the cth MTV; is the minimum hydrogen content in the cth MTV when leaving r; is the maximum hydrogen content in the cth MTV when leaving r place; (19)； (20)； (21)； (22)； (23)； (24)； The above formula represents the MTV hydrogen unloading process, where: is the equilibrium pressure when magnesium hydride releases hydrogen; The heat of hydrogen release reaction; is the steady-state temperature when magnesium hydride releases hydrogen; is the activation energy of hydrogen release; is the entropy of hydrogen release reaction; is the rate at which hydrogen is released by hydrogen refueling station r during period t; is the pre-exponential factor for hydrogen release; is the pressure in the system when magnesium hydride releases hydrogen; is the mass of magnesium hydride in hydrogenation station r during period t; is the maximum hydrogen discharge capacity of hydrogen refueling station r during period t; is the amount of hydrogen released from magnesium hydride in hydrogenation station r during period t; is the amount of hydrogen released from magnesium hydride in hydrogenation station r during period t; S2. Construct the objective function of coordinated optimization scheduling of the electricity-hydrogen system; The construction of the objective function of the coordinated optimization scheduling of the electricity-hydrogen system is as follows: Electricity-hydrogen system collaborative optimization scheduling objective function based on operating cost The lowest target mainly includes EPS operating cost and MTV transportation cost, and its expression is as follows: (25)； In the formula, EPS operating costs; transportation costs for MTV; EPS operating costs The expression is: (26)； In the formula, and They are the startup cost and shutdown cost of thermal power units respectively; is the no-load cost of thermal power units; is the operating cost of thermal power units; and It is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; It is the collection of thermal power units in the system; The MTV shipping costs The expression is: (27)； In the formula, is the fixed transportation cost of the cth MTV, is the driving cost of the cth MTV in period t, is the distance between r and r', It is the MTV quantity collection; S3. Construct the coordinated optimization scheduling constraints of the electricity-hydrogen system, including the operation constraints of the hydrogen production plant, the MTV hydrogen transportation constraints, the operation constraints of the hydrogen refueling station and the operation constraints of the power system; The expression of the constraints for the coordinated optimization of the electricity-hydrogen system scheduling is as follows: 1) Hydrogen plant operation constraints: (28)； (29)； (30)； (31)； The above formula represents the power consumed by the hydrogen production plant and the output of hydrogen; where, For the period t Hydrogen production plant h Total power consumed; For the period t Hydrogen production plant h The power consumed in compressing and purifying hydrogen; For the period t Hydrogen production plant h Power consumed in hydrogen production; The compression factor for hydrogen purification; For the period t Hydrogen production plant h The hydrogen produced; is the hydrogen production coefficient; (32)； (33)； (34)； (35)； (36)； The above formula represents the hydrogen energy balance in the hydrogen production plant, where: For the period t Hydrogen production plant h The hydrogen produced; For the period t Hydrogen production plant h The quality of hydrogen in the For the period t Hydrogen production plant h The total mass of hydrogen in magnesium hydride; For the period t Hydrogen production plant h The hydrogen produced is directly charged with hydrogen from MTV; For the period t Hydrogen production plant h The hydrogen produced is stored in the hydrogen production plant itself; For the period t Hydrogen production plant h Installed in hydrogen to MTV; For the period t Hydrogen production plant h stored hydrogen; For the period t Hydrogen production plant h Minimum hydrogen produced; For the period t Hydrogen production plant h The maximum amount of hydrogen produced; For the period t Hydrogen production plant h Minimum amount of hydrogen that can be stored; For the period t Hydrogen production plant h The maximum amount of hydrogen that can be stored; 2) Hydrogen station operation constraints: (37)； (38)； (39)； The above formula represents the hydrogen energy balance in the hydrogen refueling station, where: For the period t Hydrogen refueling station r stored hydrogen; For the period t Total hydrogen transported from MTV to site r; For the period t Hydrogen refueling station r The hydrogen load consumed; For the period t From MTV's least transport to r Total Hydrogen of Earth; For the period t From MTV to r Total Hydrogen of Earth; For the period t Hydrogen refueling station r Minimum storage of hydrogen; For the period t Hydrogen refueling station r Maximum amount of hydrogen stored; 3) The constraints of MTV hydrogen transportation are the same as those of the magnesium-based transport vehicle loading and unloading hydrogen energy operation model in step S1; 4) EPS operation constraints: Start and stop of thermal power units: (40)； Thermal power unit operation / stop time: (41)； (42)； Thermal power unit power upper and lower limits: (43)； Thermal power unit climbing constraints: (44)； (45)； Power balance within the system: (46)； In the formula, and It is a 0 / 1 state variable, indicating the start-up state and shutdown state of the thermal power unit; It is a 0 / 1 state variable, indicating whether the thermal power unit is running; is the operating power of the thermal power unit; and Respectively i The time required to start and shut down a conventional unit; and Respectively i The minimum and maximum output of conventional units; and Respectively i Ramp-up and ramp-down rates of conventional units; It is the collection of thermal power units in the system; is the set of wind turbines in the system; is the set of load nodes in the system; Indicates the number of hydrogen production plants; for t Wind turbine power during the period; for t Load output during time period; S4. Considering the uncertainty of wind energy, using information gap decision theory, a coordinated optimization scheduling model for the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is constructed; The coordinated optimization scheduling model of the electricity-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows: When the decision maker selects the IGDT opportunity model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows: (47)； In the formula, The fluctuation range of uncertain variables in the chance model; is the chance bias factor; is the optimal result under the deterministic problem; is the predicted value of wind power output; is the uncertain parameter of wind power output; represents the cost function of the model, represents an equality constraint; represents an inequality constraint; When the decision maker selects the IGDT robust model, the coordinated optimization scheduling model of the electric-hydrogen system using magnesium-based transport vehicles to transport hydrogen energy is as follows: (48)； In the formula, The fluctuation range of uncertain variables in the robust model; is the robust deviation factor; S5. Solve the scheduling model for different deviation factors. According to the objective function and constraints, use the mathematical programming model solver to solve the coordinated optimization scheduling model of the electric-hydrogen system that uses magnesium-based transport vehicles to transport hydrogen energy, so as to minimize the system operation cost.

2. The coordinated optimization scheduling method for an electric-hydrogen system using a magnesium-based transport vehicle to transport hydrogen energy according to claim 1 is characterized in that: In step S4, the wind power output uncertainty set The expression is as follows: (49)。

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