Temperature control method and device of thermal management system

Abstract

The invention provides a temperature control method and device for a thermal management system, and the method comprises the steps: carrying out the heat flow modeling of all parts in the thermal management system, determining a fuel temperature equation and a fuel tank temperature equation, and further determining a heat flow model of the thermal management system; performing state space equation construction on the heat flow model to obtain a state space expression of the heat flow model; based on the state space expression and the fuel oil flow in the thermal management system, the temperature of fuel oil entering an engine in the thermal management system is predicted, and a prediction result of the temperature of the fuel oil entering the engine is determined; and based on the fuel oil temperature prediction result, the fuel oil flow of the thermal management system is controlled, so that the fuel oil temperature entering the engine is within the preset range. According to the mode of performing heat flow modeling on each component in the heat management system, the influence of temperature and flow change on heat transfer is fully considered, and the accuracy of temperature control of the heat management system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management system control, and in particular to a temperature control method and device for a thermal management system. Background Art

[0002] Thermal management systems often need to control the temperature of key links to achieve component protection and effective management and utilization of heat.

[0003] The existing methods generally implement temperature control of thermal management systems based on modeling methods. The existing solutions generally integrate electrical, thermal, and fluid subsystems directly based on simplified heat transfer models, and implement temperature control based on the integrated models. Due to the large differences in mathematical characteristics of different models, the overall solution is difficult and the convergence is poor, resulting in low accuracy of temperature control. Summary of the invention

[0004] The present invention provides a temperature control method and device for a thermal management system, which are used to improve the accuracy of temperature control of the thermal management system.

[0005] The present invention provides a temperature control method of a thermal management system, comprising the following steps: Performing heat flow modeling on each component in the thermal management system, determining a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determining a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Based on the state space expression and the fuel flow in the thermal management system, predicting the fuel temperature entering the engine in the thermal management system, and determining the prediction result of the fuel temperature entering the engine; Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

[0006] According to a temperature control method of a thermal management system provided by the present invention, heat flow modeling is performed on each component in the thermal management system to determine the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system, including: Based on the analysis of each component in the thermal management system, determine the relationship between the change of the fuel temperature in the fuel tank in the thermal management system and time, the delayed thermal potential of the pipeline in the thermal management system, the thermal resistance of the heat exchanger in the thermal management system, the thermal potential of the heat exchanger, the thermal resistance of the cooler in the thermal management system, and the thermal potential of the cooler; Based on the relationship between the fuel temperature and time, the delayed thermodynamic potential, the thermal resistance of the heat exchanger, the thermodynamic potential of the heat exchanger, the thermal resistance of the cooler and the thermodynamic potential of the cooler, the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system are determined.

[0007] According to a temperature control method of a thermal management system provided by the present invention, the thermal resistance of the heat exchanger and the thermodynamic force of the heat exchanger are determined based on a steady-state heat exchanger model.

[0008] According to a temperature control method of a thermal management system provided by the present invention, after obtaining the state space expression of the heat flow model, the method further includes: Inputting the actual fuel flow into the state space expression of the heat flow model to determine the predicted temperature output corresponding to the actual fuel flow; A control error is determined based on a deviation between an actual temperature corresponding to the actual fuel flow and the predicted temperature, and a state space expression of the heat flow model is adjusted based on the control error.

[0009] According to a temperature control method of a thermal management system provided by the present invention, the fuel temperature entering the engine in the thermal management system is predicted based on the state space expression and the fuel flow in the thermal management system, and the prediction result of the fuel temperature entering the engine is determined, including: Based on the state space expression and the fuel flow in the thermal management system, predicting predicted temperatures corresponding to a plurality of future step lengths; Based on the pre-constructed evaluation function, the predicted temperatures corresponding to the multiple step sizes are screened, and the determined optimal predicted temperature is used as the predicted result of the fuel temperature entering the engine.

[0010] According to a temperature control method of a thermal management system provided by the present invention, the evaluation function is determined based on an optimal control set, a state weight, and an input weight.

[0011] The present invention also provides a temperature control device of a thermal management system, comprising the following modules: A model building module, used to perform heat flow modeling on each component in the thermal management system, determine a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determine a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; A model conversion module, used for constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; A prediction module, configured to predict the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow in the thermal management system, and determine a prediction result of the temperature of the fuel entering the engine; The control module is used to control the fuel flow of the thermal management system based on the fuel temperature prediction result so that the fuel temperature entering the engine is within a preset range.

[0012] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a temperature control method of the thermal management system as described above is implemented.

[0013] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the temperature control method of the thermal management system as described in any one of the above is implemented.

[0014] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the temperature control method of the thermal management system as described above is implemented.

[0015] The temperature control method and device of the thermal management system provided by the present invention analyzes each component in the thermal management system from the perspective of heat flow, models the thermal management system, and constructs a heat flow model of the thermal management system, without the need to solve the heat exchanger equations simultaneously, which can save a lot of time and improve efficiency. At the same time, by modeling the heat flow of each component in the thermal management system, the influence of temperature and flow changes on heat transfer is fully considered, and the accuracy of temperature control of the thermal management system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a flow chart of the temperature control method of the thermal management system provided by the present invention.

[0018] Figure 2 It is a schematic diagram of the structure of the thermal management system of the aircraft provided by the present invention.

[0019] Figure 3 It is a schematic diagram of the heat flow model of the entire system provided by the present invention.

[0020] Figure 4 It is a schematic diagram of the overall heat flow model of the simplified dynamic heat exchanger provided by the present invention.

[0021] Figure 5 It is a schematic diagram of a control structure block diagram provided by the present invention.

[0022] Figure 6 It is a schematic diagram of the temperature boundary and heat flow boundary conditions provided by the present invention.

[0023] Figure 7 It is a schematic diagram of the first simulation result provided by the present invention.

[0024] Figure 8 It is a schematic diagram of the second simulation result provided by the present invention.

[0025] Fig. 9 This is a schematic diagram of the structure of the temperature control device of the thermal management system provided by the present invention.

[0026] Fig.10 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Thermal management systems often need to control the temperature of key links to achieve component protection and effective management and utilization of heat. In thermal management, it is necessary to adjust and control the temperature inside mechanical equipment, electronic equipment or buildings to ensure that they operate within the optimal temperature range. The core of thermal management is to prevent overheating. Overheating can cause system failure, performance degradation and shortened equipment life. Therefore, thermal management can improve efficiency, improve performance, extend product life, ensure safety and improve comfort.

[0029] For example, in traditional fuel-powered aircraft, air is used as the main heat sink, but with the increase in Mach number and the development of stealth technology, its cooling capacity is no longer sufficient. The aircraft thermal management system that uses fuel as the main heat sink has the advantages of large specific heat capacity, stable properties, small compensation loss, and no effect on the stealth performance of the aircraft. Therefore, this type of system is also called a fuel thermal management system. The relevant methods are generally based on a simplified heat transfer model, directly integrating electrical, thermal, and liquid subsystems, and controlling the temperature based on the integrated model. Due to the large differences in the mathematical characteristics of different models, the overall solution is difficult and the convergence is poor. It does not fully consider the energy transfer characteristics and cannot accurately reflect the dynamic characteristics of multi-energy flow, resulting in low accuracy of temperature control.

[0030] In view of the defects in the related methods, the present invention provides a temperature control method of a thermal management system. Figure 1 is a flow chart of the temperature control method of the thermal management system provided by the present invention, such as Figure 1 As shown, the method includes the following: Step 110, performing heat flow modeling on each component in the thermal management system, determining a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determining a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Step 120, constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Step 130, predicting the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow in the thermal management system, and determining a prediction result of the temperature of the fuel entering the engine; Step 140: Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

[0031] The execution subject of the temperature control method of the thermal management system provided by the present invention can be an electronic device, a component in an electronic device, an integrated circuit, or a chip. The electronic device can be a mobile electronic device or a non-mobile electronic device. Exemplarily, the mobile electronic device can be a mobile phone, a tablet computer, a laptop computer, a PDA, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc., and the non-mobile electronic device can be a server, a network attached storage (NAS), or a personal computer (PC), etc., which is not specifically limited by the present invention.

[0032] The following takes the temperature control method of the thermal management system provided by the present invention executed by a computer as an example to explain the technical solution of the present invention in detail.

[0033] In step 110, heat flow modeling is performed on each component in the thermal management system to determine the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system, and based on the fuel temperature equation and the fuel tank temperature equation, a heat flow model of the thermal management system is determined.

[0034] Take the aircraft fuel thermal management system as an example. Figure 2 The schematic diagram of the thermal management system structure of the aircraft provided by the present invention is shown. The main components of the aircraft fuel thermal management system include a fuel tank, a fuel-fuel heat exchanger (heater), a diverter, and a cooler. The fuel flows out of the fuel tank and enters the fuel supply pipeline. After being preheated by the heater, it is diverted at the diverter. A part of the fuel enters the engine combustion chamber, and the remaining part enters the oil return pipeline. After being cooled by the cooler, it returns to the fuel tank. Because the pipeline has a certain length, there are flow delay characteristics in each pipe section and the heater and cooler.

[0035] exist Figure 2 middle, is the delay of each pipe section, and the subscripts T, H, E, and C represent the fuel tank, heat exchanger, engine, and cooler, respectively; is the mass flow rate, and the subscripts f, e, r, and h represent the fuel supply pipeline, engine, fuel return pipeline, and high-temperature fuel, respectively; T is the temperature, and the subscripts Ti, To, hin, and Ho represent the tank inlet, tank outlet, hot fluid inlet, and heater outlet, respectively; For heat flow.

[0036] The fuel thermal management system is analyzed based on the heat flow method. First, the components are analyzed: For fuel tank components in fuel thermal management systems: The initial internal energy of the fuel tank can be expressed as: (1); in, c p is the specific heat capacity of the fuel.

[0037] Consider the mass flow balance and internal energy change balance in the tank: (2); (3); Consider the change in heat over time: (4); The relationship between the fuel temperature in the fuel tank and time can be obtained: (5); For pipeline components in fuel thermal management systems: From the perspective of heat flow, pipeline transport delay is regarded as a delayed thermal potential, which is expressed as: (6); in, t fp is the time required for the working fluid to flow through the pipe. If the flow rate remains constant, then , L is the length of the pipeline, and v is the fluid velocity. Since it is assumed that the delay time does not change with time, the delay of each pipe section is a different constant.

[0038] For heat exchangers in fuel thermal management systems: After knowing the heat exchange performance of the heat exchanger and the inlet temperatures of the cold and hot fluids, the outlet temperatures of the cold and hot fluids can be calculated. The following are the expressions for the thermal resistance and thermal potential of the heat exchanger: (7); (8); (9); In the formula, subscripts c and h represent cold fluid and hot fluid respectively; K is the heat transfer coefficient, A is the heat transfer area of ​​the heat exchanger, KA is the overall thermal conductance of the heat exchanger, G c , G h are the heat capacity flows of the cold and hot fluids respectively; where a c and a hRespectively represent the ratio of the heat exchanger thermal conductance to the heat capacity flow of the cold and hot fluids.

[0039] For coolers in fuel thermal management systems: Considering the heat dissipation of the cold plate at a constant ambient temperature, the lumped parameter method can be used to establish the expression: (10); (11); In the formula, the subscript w represents the environment, K c A c is the thermal conductivity of the cooler.

[0040] Finally, the heat flow model of the whole system can be obtained, such as Figure 3 The heat flow model schematic diagram of the entire system provided by the present invention is shown in FIG.

[0041] The fuel temperature equation entering the engine in the fuel thermal management system can be obtained as: (12); in n is the number of sections of the heat exchanger, n The larger it is, the more accurate the calculated temperature value will be. Q c is the cold side heat flow; the subscript Hi indicates the heat exchanger inlet; T Hi (t- ) is expressed as The inlet temperature of the heater at the previous moment.

[0042] The fuel tank temperature equation in the fuel thermal management system is: (13); The brackets on the left side of the equation Represents the time step. The smaller the time step, the more accurate the formula.

[0043] Based on the fuel temperature equation entering the engine in the fuel thermal management system and the fuel tank temperature equation in the thermal management system, a heat flow model of the thermal management system can be determined.

[0044] Optionally, the temperature equation of the fuel entering the engine in the thermal management system and the temperature equation of the fuel tank in the thermal management system may be directly used as the heat flow model of the thermal management system.

[0045] In step 120, a state-space equation is constructed for the heat flow model to obtain a state-space expression of the heat flow model.

[0046] After obtaining the heat flow model determined by the fuel temperature equation entering the engine and the fuel tank temperature equation, the heat flow model is transformed into a state space expression for control.

[0047] The control variables are selected as the oil tank temperature and the oil flow rate minus their respective reference values, that is, (14); The control input is the fuel flow rate change rate of the fuel supply pipeline: (15); The control output (target) is the fuel temperature entering the engine minus the reference value: (16); The corresponding state space equations are expressed as: (17); (18); in The subscript c represents continuous time, and the subscript delay represents delay.

[0048] Optionally, the state-space expression can be further discretized.

[0049] Perform a forward Euler discretization on the state-space expression: (19); The discrete state space expression can be obtained

[0050] (20); (twenty one); in, is the time step, let , , analyzing the delay time of the entire system, it is easy to know that n is always greater than m, so Under the condition of , we expand equations (20) and (21) in the time domain and obtain the following augmented equations: (twenty two); (twenty three); Finally, the obtained state space expression can be expressed in the following simplified form: (twenty four); (25); In step 130, based on the state space expression and the fuel flow in the thermal management system, the temperature of the fuel entering the engine in the thermal management system is predicted to determine the predicted result of the temperature of the fuel entering the engine.

[0051] Based on the state space expression determined above and the fuel flow rate obtained in real time in the thermal management system, the fuel temperature of the engine is predicted, thereby determining the prediction result of the fuel temperature entering the engine.

[0052] In step 140, based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature of the engine is within a preset range.

[0053] After obtaining the predicted result of the fuel temperature, the fuel flow needs to be controlled according to the preset fuel temperature range, so as to indirectly adjust the fuel temperature.

[0054] Specifically, by adjusting the fuel flow rate to control the temperature, it is possible to ensure that the temperature of the fuel entering the engine is as stable as possible while meeting the fuel quantity requirements of the engine. It can ensure that the engine can maintain a suitable fuel temperature under different operating conditions, thereby improving its operating efficiency and reliability.

[0055] The temperature control method of the thermal management system provided by the present invention analyzes each component in the thermal management system from the perspective of heat flow, models the thermal management system, and constructs a heat flow model of the thermal management system. There is no need to solve the heat exchanger equations simultaneously, which can save a lot of time and improve efficiency. At the same time, by modeling the heat flow of each component in the thermal management system, the influence of temperature and flow changes on heat transfer is fully considered, and the accuracy of temperature control of the thermal management system is improved.

[0056] In one embodiment, heat flow modeling is performed on each component in a thermal management system to determine a temperature equation of the fuel entering the engine in the thermal management system and a temperature equation of the fuel tank in the thermal management system, including: determining, based on an analysis of each component in the thermal management system, a relationship between the change in temperature of the fuel in the fuel tank with time, a delayed thermodynamic potential of a pipeline in the thermal management system, a thermal resistance of a heat exchanger in the thermal management system, a thermodynamic potential of the heat exchanger, a thermal resistance of a cooler in the thermal management system, and a thermodynamic potential of the cooler; and determining a temperature equation of the fuel entering the engine in the thermal management system and a temperature equation of the fuel tank in the thermal management system based on a relationship between the change in temperature of the fuel with time, the delayed thermodynamic potential, the thermal resistance of the heat exchanger, the thermodynamic potential of the heat exchanger, the thermal resistance of the cooler, and the thermodynamic potential of the cooler.

[0057] In the thermal management system, the change of fuel temperature is a complex process, which involves the interaction of multiple factors. In order to determine the fuel temperature equation entering the engine and the fuel tank temperature equation, it is necessary to consider the relationship between the change of fuel temperature over time, delayed thermal potential, thermal resistance and thermal potential of the heat exchanger, thermal resistance and thermal potential of the cooler, etc.

[0058] The main components of the fuel thermal management system include the fuel tank, fuel-fuel heat exchanger (heater), splitter, and cooler. The fuel flows out of the fuel tank into the fuel supply pipeline, and after being preheated by the heater, it is split at the splitter, with one part entering the engine combustion chamber and the rest entering the oil return pipeline, where it is cooled by the cooler and then returned to the fuel tank. Because the pipeline has a certain length, there are flow delay characteristics in each pipe section and the heater and cooler.

[0059] Based on the perspective of heat flow, by analyzing the various components in the thermal management system, we can determine the relationship between the change of fuel temperature in the fuel tank in the thermal management system and time, the delayed thermal potential of the pipeline in the thermal management system, the thermal resistance of the heat exchanger in the thermal management system, the thermal potential of the heat exchanger, the thermal resistance of the cooler in the thermal management system, and the thermal potential of the cooler.

[0060] Among them, delayed thermal momentum is usually related to the thermal inertia of the system, that is, the response speed of the system to heat input. The thermal resistance of the heat exchanger is one of the key factors affecting the cooling effect of the fuel. The greater the thermal resistance, the worse the cooling effect. The thermal resistance and thermal momentum of the cooler are similar to those of the heat exchanger, but the main function of the cooler is to exchange heat between the cooling medium (such as ram air) and the fuel to reduce the fuel temperature. The thermal resistance and thermal momentum of the cooler also affect the cooling effect. The temperature of the fuel entering the engine is not only related to the tank temperature, but also affected by the cooling system and the fuel delivery system.

[0061] In one embodiment, the thermal resistance of the heat exchanger and the thermodynamic potential of the heat exchanger are determined based on a steady-state heat exchanger model.

[0062] Specifically, due to the segmented consideration of the heat exchanger, the expression will be very complicated and not easy to use it for the control model, so a simplified dynamic heat exchanger system model of the steady-state heat exchanger model considering the delay is used for control.

[0063] At this time, the difference between the inlet temperatures of the cold and hot fluids is the driving force of the heat transfer process, the heat transfer amount is the heat flow caused by the driving force, and the ratio of the driving force to the heat flow is the thermal resistance of the countercurrent heat exchanger. R The expression is: (26); Finally, we can get Figure 4 Schematic diagram of the overall heat flow model of the simplified dynamic heat exchanger provided by the present invention.

[0064] In one embodiment, after obtaining the state-space expression of the heat flow model, the method further includes: inputting the actual fuel flow into the state-space expression of the heat flow model to determine the predicted temperature output corresponding to the actual fuel flow; determining a control error based on a deviation between the actual temperature corresponding to the actual fuel flow and the predicted temperature, and adjusting the state-space expression of the heat flow model based on the control error.

[0065] Inputting the actual fuel flow into the state space expression of the heat flow model and adjusting the model based on the control error is an iterative and optimization process. By continuously adjusting and improving the model, its prediction accuracy and robustness can be improved, providing strong support for the optimization and control of the fuel system.

[0066] It is necessary to calculate the control error to perform feedback adjustment to eliminate the static error. The control structure block diagram is as follows: Figure 5 The control structure block diagram provided by the present invention is shown in the schematic diagram.

[0067] Using the forward Euler integrator, the output of the integrator can be obtained, and the deviation of the next time step is expressed as: (27); Since the system is locally linearized around a point, the reference signal r in the figure k is zero. Finally, the state space expression of the entire system is obtained: (28); (29); In one embodiment, based on the state space expression and the fuel flow in the thermal management system, the fuel temperature entering the engine in the thermal management system is predicted, and the predicted result of the fuel temperature entering the engine is determined, including: predicting the predicted temperature corresponding to multiple future step lengths based on the state space expression and the fuel flow in the thermal management system; based on a pre-constructed evaluation function, screening the predicted temperatures corresponding to the multiple step lengths, and using the determined optimal predicted temperature as the fuel temperature prediction result of the engine. The evaluation function is determined based on the optimal control set, the weight of the state, and the weight of the input. Among them, the optimal control step length is found within the prediction interval, and it is applied to the pump / valve execution to achieve the preset fuel temperature target entering the engine.

[0068] Determine the optimal control set U: (30); Minimize the following evaluation function: (31); Where N is the number of time steps forward in the forecast time, Q , P Process status x k (k=0:N-1) and terminal state x N The weights of are usually semi-positive definite matrices, R is the input weight, usually a positive definite matrix, where R is a scalar.

[0069] The formula (31) can be expanded to: (32); According to formula (28), the states of the next few steps can be predicted: (33); According to the prediction model, the state sequence within N steps is written as: (34); Substituting into formula (32) and simplifying it, we get: (35); in , Y , H , F are all about matrices Q, W, , S, The composite matrix.

[0070] When taking the limit of equation (35), we have: (36); The optimal solution can be obtained analytically as: (37); The optimal control is executed in a single step, that is, the optimal control scheme can be obtained under the changing boundary conditions in a rolling manner.

[0071] Model predictive control with constraints considers the constraints on the input and / or output of the system. Considering the output of the system is constrained, it takes the form of: (38); Formula (38) can also be written as: (39); Combining formula (30), it can be written as: (40); in, ; Optionally, a full flight profile scenario is selected, which includes seven operating states of the aircraft, including take-off, cruise, afterburner, and landing. The boundary conditions shown in Table 1 are given.

[0072] Table 1 Boundary conditions

[0073] In order to compare the control performance of the heat flow model with that of the simplified heat transfer model, the boundary conditions need to be as consistent as possible. Since the simplified heat transfer model does not know the effect of temperature and flow changes on heat transfer, the heat flow boundary used here is the one obtained by the reference heat flow model. Q c The two boundary conditions are as follows Figure 6 As shown in the schematic diagram of the temperature boundary and heat flow boundary conditions provided by the present invention, the temperature boundary is used as a controller of the heat flow model, while the heat flow boundary is used to simplify the heat transfer model.

[0074] The system model and controller model are built using the matlab / simulink platform. The system simulation models are all heat flow models of multi-stage dynamic heat exchanger systems, and the controller models use a heat flow model and a simplified heat transfer model respectively.

[0075] The fuel-fuel heat exchanger in this system is a countercurrent heat exchanger. A 10-stage dynamic heat exchanger model is used in the simulation. The partition material is aviation aluminum 5A02, and M is 3.7 kg. c p,wall is 947J / (kg·K), the heat exchanger coefficient KA Take 480W / K, the mass flow rate of the heat fluid in the heat exchanger is 0.5kg / s, and the delay time of the fuel passing through the heat exchanger is The remaining given parameter conditions are shown in Table 2 below.

[0076] Table 2 Other initial conditions and known parameters

[0077] Through simulation calculation, the final control simulation results are as follows Figure 7 The first simulation result schematic diagram provided by the present invention is shown as follows: Figure 8 The second simulation result provided by the present invention is shown in the schematic diagram. The simulation results show that, since the heat flow modeling can more accurately reflect the changing law of heat exchange with temperature difference, compared with the simplified heat transfer modeling, the example can achieve performance benefits such as a 33.3% reduction in average absolute deviation and an 82.2% reduction in control instability time. Among them, the initial value is affected at time 0 and time 1928, and the simplified heat transfer model is repeatedly adjusted at time 1928 and time 7270 due to model mismatch. See the following table 3 for control effect quantification comparison table and table 4 for disturbance stability time comparison table.

[0078] Table 3 Quantitative comparison of control effects

[0079] Table 4 Comparison of disturbance stability time

[0080] The temperature control device of the thermal management system provided by the present invention is described below. The temperature control device of the thermal management system described below and the temperature control method of the thermal management system described above can be referred to each other.

[0081] like Fig. 9 As shown, the device comprises: A model building module 910 is used to perform heat flow modeling on each component in the thermal management system, determine a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determine a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; A model conversion module 920 is used to construct a state space equation for the heat flow model to obtain a state space expression of the heat flow model; A prediction module 930, configured to predict the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow rate in the thermal management system, and determine a prediction result of the temperature of the fuel entering the engine; The control module 940 is used to control the fuel flow of the thermal management system based on the fuel temperature prediction result so that the fuel temperature of the engine is within a preset range.

[0082] The temperature control device of the thermal management system provided by the present invention analyzes each component in the thermal management system from the perspective of heat flow, models the thermal management system, and constructs a heat flow model of the thermal management system, without the need to solve the heat exchanger equations simultaneously, which can save a lot of time and improve efficiency. At the same time, by modeling the heat flow of each component in the thermal management system, the influence of temperature and flow changes on heat transfer is fully considered, and the accuracy of temperature control of the thermal management system is improved.

[0083] In one embodiment, the model building module 910 is specifically used to: The heat flow modeling of each component in the thermal management system is performed to determine the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system, including: Based on the analysis of each component in the thermal management system, determine the relationship between the change of the fuel temperature in the fuel tank in the thermal management system and time, the delayed thermal potential of the pipeline in the thermal management system, the thermal resistance of the heat exchanger in the thermal management system, the thermal potential of the heat exchanger, the thermal resistance of the cooler in the thermal management system, and the thermal potential of the cooler; Based on the relationship between the fuel temperature and time, the delayed thermodynamic potential, the thermal resistance of the heat exchanger, the thermodynamic potential of the heat exchanger, the thermal resistance of the cooler and the thermodynamic potential of the cooler, the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system are determined.

[0084] In one embodiment, the model building module 910 is further specifically configured to: The thermal resistance of the heat exchanger and the thermodynamic potential of the heat exchanger are determined based on a steady-state heat exchanger model.

[0085] In one embodiment, the model conversion module 920 is specifically used to: After obtaining the state space expression of the heat flow model, the method further includes: Inputting the actual fuel flow into the state space expression of the heat flow model to determine the predicted temperature output corresponding to the actual fuel flow; A control error is determined based on a deviation between an actual temperature corresponding to the actual fuel flow and the predicted temperature, and a state space expression of the heat flow model is adjusted based on the control error.

[0086] In one embodiment, the prediction module 930 is specifically used to: The step of predicting the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow in the thermal management system, and determining the prediction result of the temperature of the fuel entering the engine includes: Based on the state space expression and the fuel flow in the thermal management system, predicting predicted temperatures corresponding to a plurality of future step lengths; Based on a pre-constructed evaluation function, the predicted temperatures corresponding to the multiple step sizes are screened, and the determined optimal predicted temperature is used as the fuel temperature prediction result of the engine.

[0087] In one embodiment, the prediction module 930 is further specifically configured to: The evaluation function is determined based on the optimal control set, the weight of the state and the weight of the input.

[0088] Fig.10 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.10As shown, the electronic device may include: a processor 1010, a communication interface 1020, a memory 1030 and a communication bus 1040, wherein the processor 1010, the communication interface 1020 and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 may call the logic instructions in the memory 1030 to execute the temperature control method of the thermal management system, the method comprising: performing heat flow modeling on each component in the thermal management system, determining the fuel temperature equation of the fuel entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system, and determining the heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Based on the state space expression and the fuel flow in the thermal management system, predicting the fuel temperature entering the engine in the thermal management system, and determining the prediction result of the fuel temperature entering the engine; Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

[0089] In addition, the logic instructions in the above-mentioned memory 1030 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0090] On the other hand, the present invention further provides a computer program product, the computer program product includes a computer program, the computer program can be stored in a non-transitory computer-readable storage medium, when the computer program is executed by a processor, the computer can execute the temperature control method of the thermal management system provided by the above methods, the method comprising: performing heat flow modeling on each component in the thermal management system, determining a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determining a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Based on the state space expression and the fuel flow in the thermal management system, predicting the fuel temperature entering the engine in the thermal management system, and determining the prediction result of the fuel temperature entering the engine; Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

[0091] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the temperature control method of the thermal management system provided by the above methods, the method comprising: performing heat flow modeling on each component in the thermal management system, determining a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determining a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Based on the state space expression and the fuel flow in the thermal management system, predicting the fuel temperature entering the engine in the thermal management system, and determining the prediction result of the fuel temperature entering the engine; Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

[0092] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0093] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A temperature control method for a thermal management system, characterized in that: The method comprises: Performing heat flow modeling on each component in the thermal management system, determining a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determining a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; Constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; Based on the state space expression and the fuel flow in the thermal management system, predicting the fuel temperature entering the engine in the thermal management system, and determining the prediction result of the fuel temperature entering the engine; Based on the fuel temperature prediction result, the fuel flow of the thermal management system is controlled so that the fuel temperature entering the engine is within a preset range.

2. The temperature control method of the thermal management system according to claim 1, characterized in that: The heat flow modeling of each component in the thermal management system is performed to determine the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system, including: Based on the analysis of each component in the thermal management system, determine the relationship between the change of the fuel temperature in the fuel tank in the thermal management system and time, the delayed thermal potential of the pipeline in the thermal management system, the thermal resistance of the heat exchanger in the thermal management system, the thermal potential of the heat exchanger, the thermal resistance of the cooler in the thermal management system, and the thermal potential of the cooler; Based on the relationship between the fuel temperature and time, the delayed thermodynamic potential, the thermal resistance of the heat exchanger, the thermodynamic potential of the heat exchanger, the thermal resistance of the cooler and the thermodynamic potential of the cooler, the fuel temperature equation entering the engine in the thermal management system and the fuel tank temperature equation in the thermal management system are determined.

3. The temperature control method of the thermal management system according to claim 2, characterized in that: The thermal resistance of the heat exchanger and the thermodynamic potential of the heat exchanger are determined based on a steady-state heat exchanger model.

4. The temperature control method of a thermal management system according to claim 1, characterized in that: After obtaining the state space expression of the heat flow model, the method further includes: Inputting the actual fuel flow into the state space expression of the heat flow model to determine the predicted temperature output corresponding to the actual fuel flow; A control error is determined based on a deviation between an actual temperature corresponding to the actual fuel flow and the predicted temperature, and a state space expression of the heat flow model is adjusted based on the control error.

5. The temperature control method of the thermal management system according to claim 1, characterized in that: The step of predicting the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow in the thermal management system, and determining the prediction result of the temperature of the fuel entering the engine includes: Based on the state space expression and the fuel flow in the thermal management system, predicting predicted temperatures corresponding to a plurality of future step lengths; Based on a pre-constructed evaluation function, the predicted temperatures corresponding to the multiple step sizes are screened, and the determined optimal predicted temperature is used as the fuel temperature prediction result of the engine.

6. The temperature control method of the thermal management system according to claim 5, characterized in that: The evaluation function is determined based on the optimal control set, the weight of the state and the weight of the input.

7. A temperature control device for a thermal management system, characterized in that: include: A model building module, used to perform heat flow modeling on each component in the thermal management system, determine a fuel temperature equation entering the engine in the thermal management system and a fuel tank temperature equation in the thermal management system, and determine a heat flow model of the thermal management system based on the fuel temperature equation and the fuel tank temperature equation; A model conversion module, used for constructing a state space equation for the heat flow model to obtain a state space expression of the heat flow model; A prediction module, configured to predict the temperature of the fuel entering the engine in the thermal management system based on the state space expression and the fuel flow in the thermal management system, and determine a prediction result of the fuel temperature entering the engine; The control module is used to control the fuel flow of the thermal management system based on the fuel temperature prediction result so that the fuel temperature entering the engine is within a preset range.

8. 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, the temperature control method of the thermal management system according to any one of claims 1 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the temperature control method of the thermal management system according to any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the temperature control method of the thermal management system according to any one of claims 1 to 6 is implemented.

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