A method and device for thermal management control of a fuel cell cogeneration system

Abstract

The application relates to a heat management control method and device of a fuel cell combined heat and power system, wherein the control method comprises the following steps: obtaining a stack inlet temperature and calculating a difference between the stack inlet temperature and a target working temperature of a stack; determining a control compensation amount according to the difference; obtaining a heat storage tank temperature of a heat storage loop; switching a state of the fuel cell combined heat and power system according to the stack inlet temperature and the heat storage tank temperature; determining a regulation target and a control amount according to the state of the fuel cell combined heat and power system and the control compensation amount; and controlling the regulation target by using the determined control amount. The application can realize waste heat recovery and temperature control.

Description

Technical Field

[0001] This invention relates to the field of fuel cell application technology, and in particular to a thermal management control method and apparatus for a fuel cell combined heat and power system. Background Technology

[0002] With the development of human industrialization, energy issues and environmental crises have become increasingly prominent. The development of new energy sources has become a hot topic in countries around the world, and fuel cells are widely regarded as one of the most promising new energy technologies for the future. Among them, proton exchange membrane fuel cells (PEMFCs) are fuel cells that use proton-conductive polymer membranes as electrolytes. They have excellent stability and produce only water as a byproduct. They also feature low operating temperature, high power density, ease of maintenance and management, convenient start-up and shutdown, and cleanliness, making them highly valuable and commercially viable.

[0003] Inside a fuel cell stack, the electrochemical reaction between hydrogen and oxygen generates electricity, but also produces a significant amount of heat. This heat is removed by cooling water and a cooling fan, resulting in considerable energy waste. Simultaneously, the stack's operating temperature has a crucial impact on its performance and lifespan. Excessive temperature can cause dehydration of the proton exchange membrane, leading to irreversible performance degradation. Conversely, low temperatures prevent the catalyst from reaching its optimal activity, resulting in low stack efficiency. Existing fuel cell cogeneration (CHP) management systems often employ simplistic control strategies, focusing solely on heat recovery without considering the complex operating conditions of the stack or the balance between heat generation, dissipation, and recovery. Furthermore, they fail to consider the coolant temperature during stack operation, thus failing to achieve precise temperature control while simultaneously recovering heat. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a thermal management and control method and device for a fuel cell cogeneration system, which can realize waste heat recovery and temperature control.

[0005] The technical solution adopted by this invention to solve its technical problem is: to provide a thermal management and control method for a fuel cell cogeneration system, applied to a fuel cell cogeneration system, wherein the fuel cell cogeneration system includes at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, comprising the following steps:

[0006] Obtain the fuel cell inlet temperature and calculate the difference between the fuel cell inlet temperature and the target operating temperature of the fuel cell.

[0007] The control compensation amount is determined based on the difference.

[0008] Obtain the temperature of the thermal storage tank in the thermal storage loop;

[0009] The state of the fuel cell combined heat and power system is switched according to the inlet temperature of the fuel cell stack and the temperature of the heat storage tank.

[0010] The regulation target and control quantity are determined based on the state and control compensation quantity of the fuel cell cogeneration system.

[0011] The control target is controlled by a defined control quantity.

[0012] When determining the control compensation amount based on the difference, by... Determine the control compensation amount, where y(k) is the control compensation amount at time k, ΔT(k) is the difference between the stack inlet temperature and the target operating temperature of the stack at time k, and K p and K i These are the proportional parameter and the integral parameter, respectively.

[0013] The specific steps of switching the state of the fuel cell cogeneration system based on the stack inlet temperature and the heat storage tank temperature are as follows:

[0014] When the inlet temperature of the battery stack is less than or equal to the target operating temperature of the battery stack, the battery cogeneration system switches to the first state;

[0015] When the inlet temperature of the fuel cell stack is greater than the target operating temperature of the fuel cell stack, and the temperature of the thermal storage tank is greater than or equal to the maximum allowable temperature of the thermal storage tank, the battery cogeneration system switches to the second state.

[0016] When the inlet temperature of the fuel cell stack is greater than the target operating temperature of the fuel cell stack, and the temperature of the thermal storage tank is less than the maximum allowable temperature of the thermal storage tank, the battery cogeneration system switches to the third state.

[0017] The determination of the regulation target and control quantity based on the state and control compensation of the fuel cell cogeneration system specifically includes:

[0018] When the battery cogeneration system is switched to the first state, the stack thermal management circuit is switched to the heating circuit, the heat dissipation circuit, the heat exchange circuit and the heat storage circuit are closed, the first control quantity σ1=y / G(P) is output, and the first control quantity is used as the power setting value of the heating rod in the heating circuit.

[0019] When the battery cogeneration system switches to the second state, the stack thermal management circuit is switched to the heat dissipation circuit, the heating circuit, heat exchange circuit and heat storage circuit are turned off, the second control quantity σ2=y / G(D) is output, and the second control quantity is used as the duty cycle setting value of the fan in the heat dissipation circuit.

[0020] When the battery cogeneration system switches to the third state, the stack thermal management circuit is switched to the heat exchange circuit, the heat storage circuit is started, the heating circuit and the heat dissipation circuit are closed, the third control quantity σ3=y / G(r) is output, and the third control quantity is used as the speed setting value of the circulating water pump in the heat storage circuit.

[0021] Where σ1, σ2, and σ3 are the first control quantity, the second control quantity, and the third control quantity, respectively; y is the control compensation quantity; and G(P), G(D), and G(r) are obtained from open-loop testing of the controlled object, representing the power of the heating rod, the duty cycle of the fan, and the speed of the circulating water pump required when the inlet temperature of the fuel cell stack changes by the same order of magnitude.

[0022] When the control target is a heating rod in a heating circuit, the specific steps include:

[0023] The required power P of the heating rod is determined based on the difference between the operating temperature of the fuel cell stack and the outlet temperature of the heating rod. ptc ;

[0024] Based on the temperature difference ΔT between the inlet and outlet of the heating rod ptc By relating the transfer function expression to the power required by the heating rod, we can obtain the temperature that can be raised to the required power level of the heating rod; where the transfer function expression is ΔT. ptc =k ptc ·P ptc k ptc This is the proportionality coefficient;

[0025] The input temperature of the electric heater is compensated to the temperature that can be reached under the power required by the heating rod, and the output temperature is obtained.

[0026] When the control target is a fan in a heat dissipation circuit, the specific steps include:

[0027] The required duty cycle D of the fan is determined based on the difference between the outlet temperature of the air-cooled radiator and the operating temperature of the fuel cell stack.

[0028] Based on the temperature difference ΔT between the inlet and outlet of the air-cooled radiator r The transfer function expression for the required duty cycle of the fan yields the temperature drop that the fan can achieve at the required duty cycle; where the transfer function expression is ΔT. r =k r ·P r ·D,P r The total heat dissipation power of the air-cooled radiator, k r This is the proportionality coefficient;

[0029] The input temperature of the air-cooled radiator is compensated to the temperature that the fan can drop to under the required duty cycle, and the output temperature is obtained.

[0030] When the control target is a circulating water pump in a heat exchange circuit, the specific control method used to control the target includes:

[0031] The required rotational speed r of the circulating water pump is determined based on the difference between the hot-side outlet temperature and the inlet temperature of the water-cooled heat exchanger. pumb2 ;

[0032] Based on the hot-side temperature difference ΔT of the water-cooled heat exchanger ex,h The required speed r of the circulating water pump pumb2 Temperature difference ΔT between the cold side and the water-cooled heat exchanger ex,c From the transfer function expression, the required rotational speed r of the circulating water pump can be obtained. pumb2 The temperature at which the hot side of the water-cooled heat exchanger decreases; where the transfer function expression is ΔT. ex,h =k ex ·r pumb2 ·ΔT ex,c , where k ex This is the proportionality coefficient;

[0033] Compensate the hot-side input temperature of the water-cooled heat exchanger to the required speed (r) of the circulating water pump. pumb2 The output temperature is obtained by measuring the temperature drop on the hot side of the water-cooled heat exchanger.

[0034] The technical solution adopted by this invention to solve its technical problem is: to provide a thermal management control device for a fuel cell cogeneration system, applied to the fuel cell cogeneration system, wherein the fuel cell cogeneration system includes at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, comprising:

[0035] The calculation module is used to obtain the inlet temperature of the fuel cell stack and calculate the difference between the inlet temperature and the target operating temperature of the fuel cell stack.

[0036] The control compensation module is used to determine the control compensation amount based on the difference.

[0037] The acquisition module is used to acquire the temperature of the thermal storage tank in the thermal storage loop;

[0038] A state switching module is used to switch the state of the fuel cell cogeneration system according to the inlet temperature of the fuel cell stack and the temperature of the heat storage tank.

[0039] The control module is used to determine the control target and control quantity based on the state and control compensation amount of the fuel cell cogeneration system;

[0040] The control module is used to control the control target using a defined control quantity.

[0041] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-mentioned thermal management control method for a fuel cell cogeneration system.

[0042] The technical solution adopted by the present invention to solve its technical problem is: to provide a computer-readable storage medium on which a computer program is stored, wherein when the computer program is executed by a processor, the steps of the above-mentioned thermal management control method for a fuel cell cogeneration system are implemented.

[0043] Beneficial effects

[0044] Due to the adoption of the above-mentioned technical solutions, the present invention has the following advantages and positive effects compared with the prior art: Based on the optimization of the thermal management structure of the cogeneration system, the present invention combines waste heat recovery with fuel cell stack temperature control, fully considers various operating conditions of the cogeneration system, and considers different loop switching principles for each condition, making temperature control more precise; at the same time, it fully considers the heat recovery requirements, realizing the normal and stable operation of the fuel cell stack and the maximum heat recovery of the system. Attached Figure Description

[0045] Figure 1 This is a flowchart of the thermal management and control method of the fuel cell cogeneration system according to the first embodiment of the present invention;

[0046] Figure 2 This is a schematic diagram of a fuel cell combined heat and power system;

[0047] Figure 3 This is a diagram showing the input-output relationships of various components in a fuel cell combined heat and power system.

[0048] Figure 4 This is a thermal management control strategy diagram of the fuel cell cogeneration system according to the first embodiment of the present invention;

[0049] Figure 5 This is the control flowchart of the fuel cell cogeneration system in this embodiment. Detailed Implementation

[0050] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0051] The first embodiment of the present invention relates to a thermal management and control method for a fuel cell cogeneration system, which is applied to the fuel cell cogeneration system, wherein the fuel cell cogeneration system includes at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, such as... Figure 1 As shown, the process includes the following steps: obtaining the stack inlet temperature and calculating the difference between the stack inlet temperature and the stack target operating temperature; determining a control compensation amount based on the difference; obtaining the temperature of the thermal storage tank in the thermal storage loop; switching the state of the fuel cell cogeneration system based on the stack inlet temperature and the thermal storage tank temperature; determining the regulation target and control amount based on the state of the fuel cell cogeneration system and the control compensation amount; and controlling the regulation target using the determined control amount.

[0052] The fuel cell combined heat and power system in this implementation includes: Fuel cell cooling subsystem components: fuel cell stack, heating rod, three-way valve 1#, three-way valve 2#, air-cooled radiator, circulating water pump, and water-cooled heat exchanger (hot side). Waste heat utilization subsystem components: water-cooled heat exchanger (cold side), flow meter, circulating water pump 2#, heat storage tank, water supply solenoid valve, hot water supply pump, and electric heater. Figure 3 The input-output relationships of each component are given. Figure 4 A block diagram of the system control strategy is given.

[0053] The specific implementation steps of the control strategy are as follows:

[0054] Step 1: Collect the following sensor data within the system: fuel cell stack coolant outlet temperature T1, fuel cell stack coolant inlet temperature T2, water-cooled heat exchanger (hot side) inlet temperature T3, water-cooled heat exchanger (hot side) outlet temperature T4, heat storage tank A port temperature T5, heat storage tank B port temperature T6, heat storage tank internal temperature T7, and set the fuel cell operating temperature to [value missing]. The maximum water storage temperature of the thermal storage tank is T. mstor All the above variables are in °C.

[0055] Step 2: Based on the system control objective, determine its constraints as follows:

[0056]

[0057] Step 3: Calculate the flow rate of circulating water pump #1 in the fuel cell stack heat dissipation subsystem as follows:

[0058]

[0059] In the formula, V pumb1 The flow rate of coolant driven by the pump is expressed in L / min. c represents the heat output power of the fuel cell stack, measured in kW. clρ is the specific heat capacity of the coolant, expressed in J / (kg·℃). cl This refers to the density of the coolant, expressed in kg / m³. 3 ΔT stack This represents the temperature difference between the inlet and outlet of the fuel cell stack coolant, expressed in °C.

[0060] Step 4: Set the target operating temperature of the fuel cell stack. The difference between the temperature of the fuel cell stack and the inlet temperature T2 is calculated, and the difference is recorded. The control quantity y is obtained from the input control compensation module. The control compensation module uses PI control, and its calculation method is as follows:

[0061]

[0062] Where y(k) is the control compensation quantity at time k, ΔT(k) is the difference between the stack inlet temperature and the target operating temperature of the stack at time k, and K p and K i These are the proportional and integral parameters, respectively.

[0063] Step 5: Based on the different states of the fuel cell coolant inlet temperature T2 and the thermal storage tank temperature T7, obtain the output value of the state switching module, the system state factor n.

[0064] The state switching module assigns a value to the state factor n based on the input T2 after logical judgment. The relationship between its input and output is as follows:

[0065]

[0066] Among them, T mstor This is the maximum permissible temperature of the thermal storage tank.

[0067] Step 6: Input the output y of the control compensation module and the output n of the state switching module into the normalization control module, and perform corresponding normalization operations according to different state factors.

[0068] Step 6.1: If At this point, the system needs to switch to the heating loop, with state factor n = 1. When state factor n = 1, the fuel cell stack thermal management loop switches to the heating loop, shutting down the heat dissipation loop, heat exchange loop, and heat storage loop; the output control quantity is σ = y / G(P), which is used as the power setpoint for the heating rod in the controlled object's heating loop. The specific control steps are as follows:

[0069] The heating rod outlet temperature in the fuel cell stack heat dissipation subsystem is calculated as follows:

[0070]

[0071] In the formula, T ptc1,out T represents the outlet coolant temperature of the electric heater, in °C.ptc1,in This refers to the inlet coolant temperature of the electric heater, in °C. η is the thermal power of the electric heater, measured in kW. ptc1 It is the efficiency of an electric heater in converting electrical energy into heat energy; V ptc1,cl It is the flow rate of coolant through the heating rod, measured in meters per second (m³). 3 / min.

[0072] Calculate the flow rate V of the coolant through the heating rod. ptc1,cl The calculation is as follows:

[0073] V ptc1,cl =V pumb1 ·θ

[0074] In the formula, θ represents the opening degree of the three-way valve #1, which ranges from 0 to 1. When the three-way valve #1 is fully open to the heating circuit, θ is 1; when the three-way valve #1 is fully open to both the heat dissipation circuit and the heat exchange circuit, θ is 0.

[0075] Based on the above expression, calculate the temperature difference ΔT between the inlet and outlet of the heating rod of the controlled object. ptc With the set power P ptc The transfer function expression is:

[0076] ΔT ptc =k ptc ·P ptc

[0077] In the formula, k ptc This is the proportionality coefficient.

[0078] Step 6.2: If And T7 < T mstor If heat recovery is not required, the system switches to the heat dissipation loop, state factor n = 2, and uses an air-cooled radiator for heat dissipation. When state factor n = 2, the fuel cell stack thermal management loop switches to the heat dissipation loop, shutting down the heating loop, heat exchange loop, and heat storage loop; the output control quantity is σ = y / G(D), and this output quantity is used as the duty cycle setpoint of the air-cooled radiator fan in the controlled object's heat dissipation loop. The specific control steps are as follows:

[0079] The heat dissipation of the air-cooled radiator in the fuel cell stack heat dissipation subsystem is calculated as follows:

[0080] P r =K r S a ΔT r

[0081] In the formula, P r K represents the total heat dissipation power of the air-cooled radiator, expressed in kW. r S is the overall heat transfer coefficient of the air-cooled radiator. aThis refers to the total air-side heat transfer area of ​​the air-cooled radiator, in m². 2 ;ΔT r K represents the average temperature difference between the coolant and the air. r and S a All parameters are provided in the air-cooled radiator parameter manual.

[0082] Temperature difference ΔT r The calculation method is the logarithmic mean temperature difference, and the calculation method is as follows:

[0083]

[0084] Calculate the flow rate V of the coolant through the air-cooled radiator or water-cooled heat exchanger (hot side). r,ex,cl as follows:

[0085] V r,ex,cl =V r,cl =V ex,cl =V pumb1 ·(1-θ)

[0086] In the formula, V r,cl The flow rate of coolant through the air-cooled radiator, in meters per second (m³). 3 / min;V ex,cl This refers to the flow rate of coolant through the hot side of the water-cooled heat exchanger, expressed in m³ / s. 3 / min. The relevant parameters of the air-cooled radiator can be determined based on the calculated flow rate and the parameter manual.

[0087] Based on the above expression, calculate the inlet and outlet temperature difference ΔT of the controlled object's air-cooled radiator. r The transfer function expression for the duty cycle of the air-cooled radiator is:

[0088] ΔT r =k r ·P r ·D

[0089] In the formula, D is the duty cycle of the air-cooled radiator, and k r This is the proportionality coefficient.

[0090] Step 6.3: If And T7 > T mstor If heat recovery is required, the system switches to the heat exchange loop, opens the thermal storage loop, and the state factor n = 3. A water-cooled heat exchanger and circulating water pump #2 are used to recover waste heat. When the state factor n = 3, the fuel cell stack thermal management loop switches to the heat exchange loop, simultaneously starting the thermal storage loop and shutting down the heating and cooling loops. The output control quantity is σ = y / G(r), which is used as the speed setpoint for circulating water pump #2 in the thermal storage loop of the controlled object. The specific control steps are as follows:

[0091] Based on the following efficiency formula for water-cooled heat exchangers:

[0092]

[0093] In the formula, η is the efficiency of the water-cooled heat exchanger. Under normal operating conditions, the three-way valve 1# opens to port B, V ex,cl =V pumb1 During the operation of the fuel cell stack, V pumb1 Generally, the flow rate V on the cold side of the water-cooled heat exchanger remains constant, so the flow rate can be increased or decreased by controlling the circulating water pump #2. pumb2 This enables temperature control of the hot-side outlet of the water-cooled heat exchanger.

[0094] In the above expression, since the temperature T7 inside the heat storage tank changes with the heat exchange process, the cold-side inlet temperature T6 of the water-cooled heat exchanger will also change accordingly, which in turn will lead to a temperature difference ΔT between the hot and cold sides of the water-cooled heat exchanger. ex,h The change in flow rate of circulating water pump #2 will also affect ΔT. ex,h This has an impact. Therefore, the temperature difference ΔT on the hot side of the water-cooled heat exchanger can be obtained. ex,h With the rotational speed r of circulating water pump #2 pumb2 Temperature difference ΔT between the cold side and the water-cooled heat exchanger ex,c The expression:

[0095] ΔT ex,h =k ex ·r pumb2 ·ΔT ex,c

[0096] In the formula, k ex This is the proportionality coefficient.

[0097] Among them, G(P), G(D) and G(r) are obtained from the open-loop test of the controlled object, and respectively represent the power of the heating rod, the duty cycle of the fan, and the speed of the circulating water pump required when the inlet temperature of the fuel cell stack changes by the same order of magnitude.

[0098] Based on the above steps, waste heat recovery and temperature control of a fuel cell combined heat and power system can be achieved. The control process is as follows: Figure 5 As shown, the operation process includes:

[0099] S1. System power-on, self-test, and initialization of all components.

[0100] S2. Define the range of system constraint variables T7 and T2, and determine the parameter values ​​of each component of the system, including water pump speed, maximum power of air-cooled radiator, efficiency of water-cooled heat exchanger, etc.

[0101] S3. Collect data from each sensor in the system and calculate the flow rate V of the coolant through the fuel cell stack. pumb1 .

[0102] S4. Determine the relationship between the coolant inlet temperature T2 and the stack operating temperature. The size relationship.

[0103] S5, if If the state factor is 1, the circuit will switch to the heating circuit to heat the coolant to the stack operating temperature.

[0104] S6. Design control strategies.

[0105] S7. The difference between the fuel cell stack operating temperature and the electric heater outlet temperature is input into the controller for control, and the required electric heater power P is calculated. ptc .

[0106] S8. Calculate the temperature difference ΔT between the inlet and outlet of the electric heater. ptc With the electric heater set power P ptc The transfer function expression is obtained, and the inlet and outlet temperature difference of the electric heater is obtained.

[0107] S9. Compensate the input temperature of the electric heater to the temperature difference to obtain the output temperature, and then jump to S4 for closed-loop control.

[0108] S10, if Determine the temperature T7 of the thermal storage tank and its relationship with the maximum storage temperature T of the thermal storage tank. mstor The size relationship.

[0109] S11. If T7 > T mstor If the state factor is 2, the circuit will switch to the heat dissipation circuit and use an air-cooled radiator for heat dissipation.

[0110] S12, Design control strategy.

[0111] S13. The difference between the outlet temperature of the air-cooled radiator and the operating temperature of the fuel cell stack is input into the controller for control, and the duty cycle D of the air-cooled radiator is calculated.

[0112] S14. Calculate the inlet and outlet temperature difference ΔT of the air-cooled radiator. r The transfer function expression for the duty cycle of the air-cooled radiator is derived, and the inlet and outlet temperature difference of the air-cooled radiator is calculated.

[0113] S15. Compensate the input temperature of the air-cooled radiator to the temperature difference to obtain the output temperature, and jump to S4 for closed-loop control.

[0114] S16. If T7 < T mstor Then switch to the heat exchange loop, open the heat storage loop, and use the water-cooled heat exchanger and circulating water pump #2 to recover heat, with a state factor n = 3.

[0115] S17. Design control strategies.

[0116] S18. The controller is controlled based on the difference between the hot-side outlet temperature and the inlet temperature of the water-cooled heat exchanger. The required rotational speed r of circulating water pump #2 is then calculated. pumb2 .

[0117] S19. Calculate the hot-side temperature difference ΔT of the water-cooled heat exchanger. ex,h With the rotational speed r of circulating water pump #2 pumb2 Temperature difference ΔT between the cold side and the water-cooled heat exchanger ex,c The transfer function expression is obtained, and the temperature difference on the hot side of the water-cooled heat exchanger after heat recovery is calculated.

[0118] S20. Compensate the hot-side input temperature of the water-cooled heat exchanger to the temperature difference to obtain the output temperature, and then jump to S4 for closed-loop control.

[0119] It is easy to see that, based on the optimization of the thermal management structure of the cogeneration system, this invention combines waste heat recovery with fuel cell stack temperature control, fully considers various operating conditions of the cogeneration system, and considers different loop switching principles for each condition, making temperature control more precise; at the same time, it fully considers the heat recovery requirements, realizing the normal and stable operation of the fuel cell stack and the maximum heat recovery of the system.

[0120] The second embodiment of the present invention relates to a thermal management control device for a fuel cell cogeneration system, applied to the fuel cell cogeneration system, wherein the fuel cell cogeneration system includes at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, comprising:

[0121] The calculation module is used to obtain the inlet temperature of the fuel cell stack and calculate the difference between the inlet temperature and the target operating temperature of the fuel cell stack.

[0122] The control compensation module is used to determine the control compensation amount based on the difference.

[0123] The acquisition module is used to acquire the temperature of the thermal storage tank in the thermal storage loop;

[0124] A state switching module is used to switch the state of the fuel cell cogeneration system according to the inlet temperature of the fuel cell stack and the temperature of the heat storage tank.

[0125] The control module is used to determine the control target and control quantity based on the state and control compensation amount of the fuel cell cogeneration system;

[0126] The control module is used to control the control target using a defined control quantity.

[0127] The control compensation module passes through Determine the control compensation amount, where y(k) is the control compensation amount at time k, ΔT(k) is the difference between the stack inlet temperature and the target operating temperature of the stack at time k, and K pand K i These are the proportional parameter and the integral parameter, respectively.

[0128] The state switching module includes:

[0129] The first switching unit is used to switch the battery cogeneration system to a first state when the inlet temperature of the battery stack is less than or equal to the target operating temperature of the battery stack.

[0130] The second switching unit is used to switch the battery cogeneration system to a second state when the inlet temperature of the battery stack is greater than the target operating temperature of the battery stack and the temperature of the thermal storage tank is greater than or equal to the maximum allowable temperature of the thermal storage tank.

[0131] The third switching unit is used to switch the battery cogeneration system to the third state when the inlet temperature of the battery stack is greater than the target operating temperature of the battery stack and the temperature of the thermal storage tank is less than the maximum allowable temperature of the thermal storage tank.

[0132] The control module includes:

[0133] The first control unit is used to switch the stack thermal management circuit to the heating circuit, shut down the heat dissipation circuit, heat exchange circuit and heat storage circuit when the battery cogeneration system is switched to the first state, output a first control quantity σ1=y / G(P), and use the first control quantity as the power setting value of the heating rod in the heating circuit.

[0134] The second control unit is used to switch the stack thermal management circuit to the heat dissipation circuit, shut down the heating circuit, heat exchange circuit and heat storage circuit when the battery cogeneration system switches to the second state, output the second control quantity σ2=y / G(D), and use the second control quantity as the duty cycle setting value of the fan in the heat dissipation circuit;

[0135] The third control unit is used to switch the stack thermal management circuit to the heat exchange circuit when the battery cogeneration system switches to the third state, and at the same time start the heat storage circuit, shut down the heating circuit and the heat dissipation circuit, output the third control quantity σ3=y / G(r), and use the third control quantity as the speed setting value of the circulating water pump in the heat storage circuit.

[0136] Where σ1, σ2, and σ3 are the first control quantity, the second control quantity, and the third control quantity, respectively; y is the control compensation quantity; and G(P), G(D), and G(r) are obtained from open-loop testing of the controlled object, representing the power of the heating rod, the duty cycle of the fan, and the speed of the circulating water pump required when the inlet temperature of the fuel cell stack changes by the same order of magnitude.

[0137] The control module includes a determination unit, a calculation unit, and a compensation unit. When the control target is a heating rod in the heating circuit, the determination unit determines the required power P of the heating rod based on the difference between the operating temperature of the fuel cell stack and the outlet temperature of the heating rod.ptc The calculation unit is based on the temperature difference ΔT between the inlet and outlet of the heating rod. ptc By relating the transfer function expression to the power required by the heating rod, we can obtain the temperature that can be raised to the required power level of the heating rod; where the transfer function expression is ΔT. ptc =k ptc ·P ptc k ptc The proportionality coefficient is used to compensate the input temperature of the electric heater to the temperature that the heating rod can reach under the required power, thus obtaining the output temperature.

[0138] The control module includes a determination unit, a calculation unit, and a compensation unit. When the control target is a fan in the heat dissipation circuit, the determination unit determines the required duty cycle D of the fan based on the difference between the outlet temperature of the air-cooled radiator and the operating temperature of the fuel cell stack; the calculation unit determines the required duty cycle D of the fan based on the inlet and outlet temperature difference ΔT of the air-cooled radiator. r The transfer function expression for the required duty cycle of the fan yields the temperature drop that the fan can achieve at the required duty cycle; where the transfer function expression is ΔT. r =k r ·P r ·D,P r The total heat dissipation power of the air-cooled radiator, k r The proportionality coefficient is used to compensate the input temperature of the air-cooled radiator to the temperature that the fan can drop to under the required duty cycle, thus obtaining the output temperature.

[0139] The control module includes a determination unit, a calculation unit, and a compensation unit. When the control target is the circulating water pump in the heat exchange loop, the determination unit determines the required rotational speed r of the circulating water pump based on the difference between the hot-side outlet temperature and the inlet temperature of the water-cooled heat exchanger. pumb2 The calculation unit is based on the temperature difference ΔT on the hot side of the water-cooled heat exchanger. ex,h The required speed r of the circulating water pump pumb2 Temperature difference ΔT between the cold side and the water-cooled heat exchanger ex,c From the transfer function expression, the required rotational speed r of the circulating water pump can be obtained. pumb2 The temperature at which the hot side of the water-cooled heat exchanger decreases; where the transfer function expression is ΔT. ex,h =k ex ·r pumb2 ·ΔT ex,c , where k ex The proportionality coefficient is used; the compensation unit compensates the hot-side input temperature of the water-cooled heat exchanger to the required rotational speed r of the circulating water pump. pumb2 The output temperature is obtained by measuring the temperature drop on the hot side of the water-cooled heat exchanger.

[0140] The third embodiment of the present invention relates to an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the thermal management control method of the above-described fuel cell cogeneration system.

[0141] The fourth embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the thermal management control method of the above-described fuel cell cogeneration system.

[0142] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0143] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0144] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0145] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0146] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A thermal management and control method for a fuel cell combined heat and power system, characterized in that, An application in a fuel cell combined heat and power (CHP) system, the fuel cell CHP system comprising at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, includes the following steps: Obtain the fuel cell inlet temperature and calculate the difference between the fuel cell inlet temperature and the target operating temperature of the fuel cell. The control compensation amount is determined based on the difference. Obtain the temperature of the thermal storage tank in the thermal storage loop; The state of the fuel cell cogeneration system is switched according to the inlet temperature of the fuel cell stack and the temperature of the heat storage tank, specifically as follows: When the inlet temperature of the battery stack is less than or equal to the target operating temperature of the battery stack, the battery cogeneration system switches to the first state; When the inlet temperature of the fuel cell stack is greater than the target operating temperature of the fuel cell stack, and the temperature of the thermal storage tank is greater than or equal to the maximum allowable temperature of the thermal storage tank, the battery cogeneration system switches to the second state. When the inlet temperature of the fuel cell stack is greater than the target operating temperature of the fuel cell stack, and the temperature of the thermal storage tank is less than the maximum allowable temperature of the thermal storage tank, the battery cogeneration system switches to the third state. The regulation target and control quantity are determined based on the state and control compensation of the fuel cell cogeneration system, specifically as follows: When the battery cogeneration system switches to the first state, the stack thermal management circuit is switched to the heating circuit, the heat dissipation circuit, the heat exchange circuit, and the heat storage circuit are shut down, and the first control quantity is output. And use this first control quantity as the power setting value of the heating rod in the heating circuit; When the battery cogeneration system switches to the second state, the stack thermal management circuit is switched to the heat dissipation circuit, the heating circuit, heat exchange circuit, and heat storage circuit are shut down, and the second control quantity is output. And use this second control quantity as the duty cycle setting value of the fan in the heat dissipation circuit; When the battery cogeneration system switches to the third state, the stack thermal management circuit is switched to the heat exchange circuit, the heat storage circuit is started, the heating circuit and the heat dissipation circuit are shut down, and the third control quantity is output. The third control variable is used as the speed setting value of the circulating water pump in the thermal storage circuit; in, , , These are the first control variable, the second control variable, and the third control variable, respectively. To control the amount of compensation, , and The values ​​are obtained from open-loop testing of the controlled object and represent the power of the heating rod, the duty cycle of the fan, and the speed of the circulating water pump required when the inlet temperature of the fuel cell stack changes by the same order of magnitude. The control target is controlled by a defined control quantity.

2. The thermal management and control method for a fuel cell cogeneration system according to claim 1, characterized in that, When determining the control compensation amount based on the difference, by... Determine the control compensation amount, where, for The amount of control compensation at any time, for The difference between the fuel cell inlet temperature and the target operating temperature of the fuel cell at any given time. and These are the proportional parameter and the integral parameter, respectively.

3. The thermal management and control method for a fuel cell cogeneration system according to claim 1, characterized in that, When the control target is a heating rod in a heating circuit, the specific steps include: The required power of the heating rod is determined based on the difference between the operating temperature of the fuel cell stack and the outlet temperature of the heating rod. ; Based on the temperature difference between the inlet and outlet of the heating rod By relating the transfer function to the power required by the heating rod, we can obtain the temperature that can be raised to the required power level of the heating rod; where the transfer function expression is: , This is the proportionality coefficient; The input temperature of the electric heater is compensated to the temperature that can be reached under the power required by the heating rod, and the output temperature is obtained.

4. The thermal management and control method for a fuel cell cogeneration system according to claim 1, characterized in that, When the control target is a fan in a heat dissipation circuit, the specific steps include: The required fan duty cycle is determined based on the difference between the outlet temperature of the air-cooled radiator and the operating temperature of the fuel cell stack. ; Based on the temperature difference between the inlet and outlet of the air-cooled radiator The transfer function expression for the required duty cycle of the fan is used to obtain the temperature drop that the fan can achieve at the required duty cycle; where the transfer function expression is: , This represents the total heat dissipation power of the air-cooled radiator. This is the proportionality coefficient; The input temperature of the air-cooled radiator is compensated to the temperature that the fan can drop to under the required duty cycle, and the output temperature is obtained.

5. The thermal management and control method for a fuel cell cogeneration system according to claim 1, characterized in that, When the control target is a circulating water pump in a heat exchange circuit, the specific control method used to control the target includes: The required speed of the circulating water pump is determined based on the difference between the hot-side outlet temperature and the inlet temperature of the water-cooled heat exchanger. ; Based on the temperature difference on the hot side of the water-cooled heat exchanger Speed ​​required by the circulating water pump Temperature difference on the cold side of the water-cooled heat exchanger From the transfer function expression, the required speed of the circulating water pump can be obtained. The temperature at which the hot side of the water-cooled heat exchanger decreases; where the transfer function expression is: ,in, This is the proportionality coefficient; Compensate the hot-side input temperature of the water-cooled heat exchanger to the required speed of the circulating water pump. The output temperature is obtained by measuring the temperature drop on the hot side of the water-cooled heat exchanger.

6. A thermal management and control device for a fuel cell combined heat and power system, characterized in that, This is applied to a fuel cell cogeneration system, which includes at least a heating circuit, a heat dissipation circuit, a heat exchange circuit, and a heat storage circuit, comprising: The calculation module is used to obtain the inlet temperature of the fuel cell stack and calculate the difference between the inlet temperature and the target operating temperature of the fuel cell stack. The control compensation module is used to determine the control compensation amount based on the difference. The acquisition module is used to acquire the temperature of the thermal storage tank in the thermal storage loop; A state switching module is used to switch the state of the fuel cell cogeneration system according to the inlet temperature of the fuel cell stack and the temperature of the thermal storage tank; the state switching module includes: The first switching unit is used to switch the battery cogeneration system to a first state when the inlet temperature of the battery stack is less than or equal to the target operating temperature of the battery stack. The second switching unit is used to switch the battery cogeneration system to a second state when the inlet temperature of the battery stack is greater than the target operating temperature of the battery stack and the temperature of the thermal storage tank is greater than or equal to the maximum allowable temperature of the thermal storage tank. The third switching unit is used to switch the battery cogeneration system to the third state when the inlet temperature of the battery stack is greater than the target operating temperature of the battery stack and the temperature of the heat storage tank is less than the maximum allowable temperature of the heat storage tank. The control module is used to determine the control target and control quantity based on the state and control compensation amount of the fuel cell cogeneration system; the control module includes: The first control unit is used to switch the stack thermal management circuit to the heating circuit, shut down the heat dissipation circuit, the heat exchange circuit, and the heat storage circuit when the battery cogeneration system switches to the first state, and output a first control quantity. And use this first control quantity as the power setting value of the heating rod in the heating circuit; The second control unit is used to switch the stack thermal management circuit to the heat dissipation circuit, shut down the heating circuit, heat exchange circuit, and heat storage circuit, and output a second control quantity when the battery cogeneration system switches to the second state. And use this second control quantity as the duty cycle setting value of the fan in the heat dissipation circuit; The third control unit is used to switch the stack thermal management circuit to the heat exchange circuit when the battery cogeneration system switches to the third state, simultaneously start the heat storage circuit, shut down the heating circuit and the heat dissipation circuit, and output a third control quantity. The third control variable is used as the speed setting value of the circulating water pump in the thermal storage circuit; in, , , These are the first control variable, the second control variable, and the third control variable, respectively. To control the amount of compensation, , and The values ​​are obtained from open-loop testing of the controlled object and represent the power of the heating rod, the duty cycle of the fan, and the speed of the circulating water pump required when the inlet temperature of the fuel cell stack changes by the same order of magnitude. The control module is used to control the control target using a defined control quantity.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the thermal management control method for the fuel cell cogeneration system as described in any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the thermal management control method for any of the fuel cell cogeneration systems described in claims 1-5.

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