An electric heating control method for a multi-stack fuel cell system for aviation

Abstract

The present invention belongs to the field of renewable energy power generation technology and discloses an electrothermal control method for a multi-stack fuel cell system for aviation. An experimental platform for the multi-stack fuel cell system is constructed, and a current-to-optimal temperature value reference curve under experimental conditions is obtained based on the experimental platform. In an air-cooled fuel cell system, based on actual operating conditions under different environments, the temperature value transmitted in real time by a temperature sensor installed in the fuel cell stack's air flow path is processed through a control algorithm to control the voltage value transmitted to the fuel cell stack's air intake fan by a master controller, thereby achieving temperature control of the fuel cell stack. The present invention uses fuzzy logic to control the self-anti-disturbance nonlinear state error feedback (NLSEF) parameters β1 and β2, improving the system's temperature response speed, reducing the fuel cell thermal management adjustment time, and minimizing the overshoot of the fuel cell temperature, effectively improving the output characteristics of the fuel cell stack.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy power generation, and in particular relates to an electric heating control method for a multi-stack fuel cell system for aviation. Background Art

[0002] Currently, energy is a crucial material foundation for developing the national economy and improving people's living standards, and it also directly impacts my country's economic development. With the decline of the three major fossil fuels and the environmental problems caused by the consumption of traditional energy, the traditional energy structure and its utilization methods are unlikely to meet the needs of future human survival and development. New energy has become one of the new research directions that countries around the world have begun to research. Against the backdrop of energy transformation, low-carbon aviation has become a consensus among countries around the world in developing the aviation industry, and electric aircraft, as a major direction for the development of green aviation, have received increasing attention. Among various electric systems, aviation fuel cell propulsion systems, as a power supply system with high energy density, high energy conversion efficiency, and zero pollution, have excellent characteristics that can greatly increase aircraft range.

[0003] Safety analysis plays a crucial role in the design of general aircraft avionics system architectures. The engine, as the heart of the aircraft and its power source, directly impacts its performance, reliability, and economy. Aviation fuel cell propulsion systems require high thrust during startup and climb. Due to current manufacturing limitations and fuel cell stack heat dissipation considerations, a single engine cannot meet these requirements. Engine redundancy is also necessary at the system architecture level to mitigate single engine failure and improve system-level reliability. The output performance of proton exchange membrane fuel cells is affected by factors such as operating temperature, ambient pressure, humidity, and membrane moisture content, but operating temperature is the greatest influence. Fuel cells must maintain a suitable temperature during operation. Excessively high temperatures can dry out the membrane, causing a "dry membrane" failure, reducing membrane performance and severely impacting the fuel cell's service life. Excessively low fuel cell stack temperature reduces fuel cell output power, increases fuel cell operating costs, and significantly reduces the range of fuel cell aircraft. Air-cooled proton exchange membrane fuel cells, due to their inherent structural characteristics of direct contact between the cathode inlet and air, eliminate the air compressor and humidifier and install a cooling fan. The fan not only provides air but also removes heat generated within the fuel cell stack, thereby controlling the temperature within the fuel cell stack. Therefore, controlling the cooling fan to maintain the internal temperature of the fuel cell stack within the appropriate range is a key issue in determining the performance of the fuel cell stack.

[0004] Due to the complexity of actual working conditions, it is difficult to establish an accurate mathematical model for air-cooled proton exchange membrane fuel cells. In addition, most of the controllers of air-cooled fuel cell systems currently use traditional controllers. If the modulation is intense, it is easy to cause temperature overshoot and oscillation, resulting in "membrane dry" failure, affecting the service life of the fuel cell and endangering the safety of users. If the modulation is gentle, it will cause long adjustment time and slow dynamic response, resulting in insufficient output power and fuel waste. Especially when interference occurs, the traditional controller cannot respond in time, which may cause system oscillation, overshoot and other problems, affecting the reliability of the system.

[0005] Through the above analysis, the problems and defects of the existing technology are as follows:

[0006] (1) For aviation fuel cell propulsion systems, a large thrust is required during startup and climbing. Due to the limitations of current manufacturing processes and fuel cell stack heat dissipation considerations, a single engine cannot meet the required requirements. Engine redundancy is also required at the system architecture level to prevent single engine failure and improve system-level reliability.

[0007] (2) Due to the complexity of actual operating conditions, it is difficult to establish an accurate mathematical model for air-cooled proton exchange membrane fuel cells.

[0008] (3) Currently, most controllers for air-cooled fuel cell systems still use traditional controllers. If the modulation is intense, it is easy to cause temperature overshoot and oscillation, resulting in "membrane dry" failure, affecting the service life of the fuel cell and endangering the safety of the user.

[0009] (4) If the traditional controller is used and the modulation is slow, it will cause a long adjustment time and slow dynamic response, resulting in insufficient output power and fuel waste. In particular, when interference occurs, the traditional controller cannot respond in time, which may cause system oscillation, overshoot and other problems, affecting the reliability of the system. Summary of the Invention

[0010] In response to the problems existing in the prior art, the present invention provides an electrothermal control method for a multi-stack fuel cell system for aviation, and in particular relates to the construction of a dual-engine air-cooled hydrogen fuel cell test platform based on fuzzy self-anti-interference and its thermal management control method, medium, equipment and terminal.

[0011] The present invention is implemented as follows: a method for controlling the electric heat of a multi-stack fuel cell system for aviation, the method comprising:

[0012] An experimental platform for multi-stack fuel cell systems for aviation is constructed, and a reference curve of current-optimal temperature value under experimental conditions is obtained based on the experimental platform. In air-cooled fuel cell systems, based on actual working conditions in different environments, the temperature value transmitted in real time by the temperature sensor installed in the air flow channel of the fuel cell stack is processed through a control algorithm to control the voltage value transmitted to the air intake fan of the fuel cell stack by the main controller, thereby realizing temperature control of the fuel cell stack. Compared with traditional controllers, this algorithm has faster response speed, smaller overshoot and stronger anti-interference ability.

[0013] Furthermore, the electrical and thermal control method for a multi-stack fuel cell system for aviation includes the following steps:

[0014] Step 1: Based on the aviation multi-stack fuel cell system test platform, obtain the current-optimal temperature value reference curve of the air-cooled fuel cell stack under the current test environment to facilitate temperature comparison during the experiment;

[0015] Step 2: For the air-cooled fuel cell stack under the current test environment, open the hydrogen pressure reducing valve, the air intake fan, adjust the hydrogen intake valve, set the operating current, and start the air-cooled fuel cell stack;

[0016] Step 3: Measure the stack output current, stack temperature, and fan voltage according to actual working conditions; convert the stack output current, stack temperature, and fan voltage into electrical signals through the voltage sensor, current sensor, and temperature sensor, and transmit them to the main controller;

[0017] Step 4: Processing by the main controller; according to the current-optimal temperature value reference curve fitted in step 1, the optimal temperature value corresponding to the fuel cell stack when the stack outputs current under actual working conditions is obtained; according to the actual temperature value transmitted to the controller by the temperature sensor, the temperature difference between the optimal temperature and the actual temperature is calculated; the voltage value of the air intake fan is calculated by the fuzzy self-anti-disturbance method, and fed back to the air intake fan to realize the thermal management of the aviation multi-stack fuel cell system experimental platform.

[0018] Furthermore, the current-optimal temperature value reference curve acquisition in step 1 includes:

[0019] (1) Turn on the programmable DC power supply, connect the fuel cell stack air intake fan and the main controller, turn on the intake fan to provide oxygen for the fuel cell stack reaction;

[0020] (2) Open the pressure reducing valve of the high-pressure hydrogen storage tank and adjust the hydrogen inlet valve to make the inlet pressure of the hydrogen inlet end of the fuel cell stack reach a suitable range to provide hydrogen for the fuel cell stack reaction;

[0021] (3) Adjust the electronic control system; set the fixed load operating current, perform the air-cooled fuel cell startup operation, start the fuel cell stack, and run it stably for a period of time under the operating conditions to activate the performance, which is more conducive to analyzing the output characteristics of the fuel cell stack;

[0022] (4) The air intake fan is controlled by a PWM signal. By adjusting the PWM signal of the fan so that it runs at the maximum speed, the PWM value is 100%; the temperature inside the air-cooled fuel cell stack reaches a low level of stable state, and the PWM signal value is fixedly reduced, and each reduction value is △PWM; according to the size of the fixed load working current, △PWM is set to 5-10%, so that the internal temperature of the air-cooled fuel cell stack rises slowly;

[0023] (5) If the output voltage of the air-cooled fuel cell stack is observed during the test, if the output voltage becomes lower than the output voltage corresponding to the previous PWM value, then the PWM value is stopped from being reduced; during the experiment, the internal temperature value of the air-cooled fuel cell at the moment corresponding to the maximum output voltage is the optimal temperature value under the current fixed load condition, and the temperature change graph and output voltage graph when the load current is 20A are obtained;

[0024] (6) Setting different fixed load working currents, repeating steps (1) to (5), obtaining reference temperatures under different fixed load working currents, and drawing a current-optimal temperature value reference curve.

[0025] Furthermore, the overall controller in step 4 detects the actual operating current value in real time during the processing. If the actual operating current value changes, the calculation and processing are performed according to steps 3 to 4 using the new actual operating current value.

[0026] Furthermore, the second-order fuzzy auto-disturbance rejection method in step 4 includes:

[0027] (1) The expression of the active disturbance rejection tracking differentiator is:

[0028]

[0029] Where h0 represents the step size of the fst function, h represents the sampling period, r represents the tracking speed, and V0 is the optimal temperature value corresponding to the current value;

[0030] (2) The expression of the ADRC extended state observer is:

[0031]

[0032] Among them, y represents the temperature value inside the stack at the current moment, Z1, Z2, and Z3 represent the observed values ​​of the total disturbance of the tracking signal of y, b represents the compensation factor, and β 01 , β 02 , β03 is the extended state observer parameter;

[0033] (3) The expression of the nonlinear state error feedback control rate of the ADRC is:

[0034]

[0035] Among them, V1 and V2 are derived from the active disturbance rejection tracking differentiator, and β1 and β2 are the nonlinear state error feedback NLSEF parameters;

[0036] (4) Fuzzify the nonlinear state error feedback parameters of the ADRC, select the triangular membership function as the membership function, select the fuzzy domain, and design the basic domain of input and output and the fuzzy control table;

[0037] Among them, the basic domain of input and output is:

[0038]

[0039] Among them, e represents the temperature difference between the current temperature value and the optimal temperature value, e c It is expressed as the rate of change of the temperature difference between the current temperature value and the optimal temperature value, and Δβ1 and Δβ2 are the change values ​​of parameters β1 and β2;

[0040] (5) Substitute the corrected Δβ1 and Δβ2 into the calculation formula: β1 = Δβ1 + β 10 β2=Δβ2+β 20 , and update the parameters β1 and β2.

[0041] Another object of the present invention is to provide an experimental platform for implementing the above-mentioned method for electrothermal control of a multi-stack fuel cell system for aviation. The experimental platform for a multi-stack fuel cell system for aviation includes: an electronic control system, a temperature control system, a hydrogen supply system, an exhaust system, an air-cooled fuel cell stack, a master controller, and a programmable DC power supply.

[0042] Among them, the electronic control system is connected to the power supply interface of the fuel cell stack, the temperature control system is arranged on the fuel cell stack and connected to the air supply fan of the stack; the hydrogen supply system is connected to the hydrogen inlet of the fuel cell stack, and the exhaust system is connected to the hydrogen outlet of the fuel cell stack; the main controller is respectively connected to the control interfaces of the electronic control system, the temperature control system, and the hydrogen supply system, and a voltage sensor and a current sensor are arranged in the electronic control system, a temperature sensor is arranged in the temperature control system, and a flow sensor and a pressure sensor are arranged in the hydrogen supply system. The voltage sensor, current sensor, and temperature sensor all transmit the measured working parameters to the main controller.

[0043] Furthermore, the electronic control system includes a DC / DC converter, an electronic speed regulator, a brushless DC motor, and a propeller. The power supply interface of the DC / DC converter is connected to the power supply interface of the fuel cell stack, the power supply interface of the electronic speed regulator is connected to the power supply interface of the DC / DC converter, the power supply interface of the brushless DC motor is connected to the power supply interface of the electronic speed regulator, the propeller is installed on the brushless DC motor, and the control interfaces of the DC / DC converter and the electronic speed regulator are both connected to the main controller.

[0044] The temperature control system includes a temperature sensor and an air supply fan. The temperature sensor is installed in the air flow channel of the fuel cell stack. The air supply fan is installed at the air intake end of the fuel cell stack. The power supply interface of the air supply fan is connected to a programmable DC power supply. The control port of the air supply fan is connected to the main controller.

[0045] The hydrogen supply system includes a high-pressure hydrogen storage tank, a pressure reducing valve, an intake valve, a hydrogen flow sensor, a back pressure valve, a pressure sensor, and a purge valve. The high-pressure hydrogen storage tank, the pressure reducing valve, and the intake valve are connected to the hydrogen inlet end of the fuel cell stack in sequence through a hydrogen pipeline. The back pressure valve, the pressure sensor, and the purge valve are connected to the hydrogen outlet end of the fuel cell stack in sequence. The hydrogen flow sensor is installed between the intake valve and the hydrogen inlet of the fuel cell stack to record the hydrogen usage flow and transmit the data thereof to the main controller. The pressure sensor is installed between the back pressure valve and the purge valve to record the current pressure value at the hydrogen outlet and transmit the data to the main controller. The hydrogen flow sensor is a mass flow meter.

[0046] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the electrothermal control method of a multi-stack fuel cell system for aviation.

[0047] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of the electrothermal control method for a multi-stack fuel cell system for aviation.

[0048] Another object of the present invention is to provide an information data processing terminal, which is used to implement the aviation multi-stack fuel cell system experimental platform.

[0049] In combination with the above technical solutions and the technical problems solved, please analyze the advantages and positive effects of the technical solutions to be protected by the present invention from the following aspects:

[0050] First, in view of the technical problems existing in the above-mentioned prior art and the difficulty of solving these problems, we closely combine the technical solutions to be protected by the present invention and the results and data during the research and development process, and conduct a detailed and in-depth analysis of how the technical solutions of the present invention solve the technical problems and some creative technical effects brought about by solving the problems. The specific description is as follows:

[0051] The present invention provides an electric and thermal control method for a multi-stack fuel cell system for aviation, which belongs to the field of new energy power generation technology. First, an experimental platform for the multi-stack fuel cell system for aviation is constructed, which mainly includes an electronic control system, a temperature control system, a hydrogen supply system, an exhaust system, and an air-cooled fuel cell stack; based on the experimental platform, a current-optimal temperature value reference curve under experimental conditions is obtained, and according to the actual temperature value transmitted to the controller by the temperature sensor, the temperature difference between the optimal temperature and the actual temperature is calculated, and the intake end fan voltage value is calculated by a fuzzy self-anti-interference method, and the voltage is fed back to the intake end fan, thereby realizing thermal management of the experimental platform for the multi-stack fuel cell system for aviation, effectively shortening the time for the fan to adjust the temperature, reducing the temperature overshoot, and realizing fast, stable and efficient output of the fuel cell.

[0052] This invention proposes an aviation multi-stack fuel cell system test platform that can simulate the flight conditions of a multi-stack fuel cell aircraft and flexibly adapt the system structure to meet different requirements, demonstrating its strong applicability. The proposed fuzzy auto-disturbance rejection thermal management control method for this aviation multi-stack fuel cell system test platform uses fuzzy logic to control the auto-disturbance rejection nonlinear state error feedback (NLSEF) parameters β1 and β2. This improves the system's temperature response speed, reduces fuel cell thermal management adjustment time, and minimizes fuel cell temperature overshoot, effectively enhancing the output characteristics of the fuel cell stack.

[0053] Second, considering the technical solution as a whole or from the perspective of the product, the technical effects and advantages of the technical solution to be protected by the present invention are described in detail as follows:

[0054] The present invention designs an experimental platform for a multi-stack fuel cell system for aviation and a thermal management control method based on fuzzy self-anti-disturbance control. By building the platform, an experimental basis is provided, an algorithm is designed and experimentally verified on the platform, and the feasibility of the algorithm is guaranteed. By combining the fuzzy control algorithm, the defect of traditional control algorithms in the existing technology that it is difficult to determine parameters is solved, the response speed of the fuel cell is improved, the time for the fan to adjust the temperature is shortened, the temperature overshoot is reduced, and the fast, stable and efficient output of the aviation fuel cell aircraft platform is achieved.

[0055] Third, as auxiliary evidence of the creativity of the claims of the present invention, it is also reflected in the following important aspects: the expected benefits and commercial value after the transformation of the technical solution of the present invention are: the aviation multi-stack fuel cell system experimental platform designed by the present invention fills the gap in the domestic aviation fuel cell aircraft system architecture engine redundancy experimental platform, and has excellent flexibility and system variability. It can flexibly change or replace parts according to the needs of users, and provides new solutions in the research of redundant system energy management, system power supply network design and analysis, redundant system fault-tolerant control and single system control comparison. The proposed control algorithm also provides a method and idea for the research of fuel cell thermal management. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0057] Figure 1 This is a schematic diagram of an aviation multi-stack fuel cell system experimental platform provided by an embodiment of the present invention;

[0058] Figure 2 This is a flow chart of an electric heating control method for a multi-stack fuel cell system for aviation provided by an embodiment of the present invention;

[0059] Figure 3 This is a flow chart of an air-cooled fuel cell stack control method based on fuzzy auto-disturbance rejection provided by an embodiment of the present invention;

[0060] Figure 4 This is a flow chart of obtaining a current-optimal temperature value reference curve provided by an embodiment of the present invention;

[0061] Figure 5 This is a temperature change diagram when the working current is 20A provided by an embodiment of the present invention;

[0062] Figure 6 This is a diagram of output voltage when the working current is 20A provided by an embodiment of the present invention;

[0063] Figure 7 is a reference curve diagram of current-optimum temperature value under the test environment provided by an embodiment of the present invention;

[0064] Figure 8 : is a structural diagram of a fuzzy active disturbance rejection control algorithm provided by an embodiment of the present invention;

[0065] Figure 9 This is a fuel cell stack temperature experiment diagram based on fuzzy auto-interference rejection provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0067] In response to the problems existing in the prior art, the present invention provides an electric and thermal control method for a multi-stack fuel cell system for aviation. The present invention is described in detail below with reference to the accompanying drawings.

[0068] 1. Explanatory Examples In order to enable those skilled in the art to fully understand how to implement the present invention, this section provides an illustrative example that expands upon the technical solutions of the claims.

[0069] like Figure 1 As shown, the aviation multi-stack fuel cell system experimental platform provided by the embodiment of the present invention is mainly composed of an electric control system, a temperature control system, a hydrogen supply system, an exhaust system, an air-cooled fuel cell stack (107, 108), a master controller (127), and a programmable DC power supply (128); the electric control system is connected to the power supply interface of the fuel cell stack (107, 108), the temperature control system is arranged on the fuel cell stack (107, 108) and connected to the air supply fan (123, 124) of the stack, the hydrogen supply system is connected to the hydrogen inlet of the fuel cell stack (107, 108), the exhaust system is connected to the hydrogen outlet of the fuel cell stack (107, 108), the master controller (127) is respectively connected to the control interfaces of the electric control system, the temperature control system, and the hydrogen supply system, a voltage sensor and a current sensor are arranged in the electric control system, a temperature sensor is arranged in the temperature control system, and a flow sensor and a pressure sensor are arranged in the hydrogen supply system, and the voltage sensor, the current sensor, and the temperature sensor all transmit the measured working parameters to the master controller (127).

[0070] The electric control system provided by the embodiment of the present invention comprises a DC / DC converter (105, 106), an electronic speed regulator (103, 104), a brushless DC motor (101, 102), and a propeller (129, 130). The power supply interface of the DC / DC converter (105, 106) is connected to the power supply interface of the fuel cell stack (107, 108), the power supply interface of the electronic speed regulator (103, 104) is connected to the power supply interface of the DC / DC converter (105, 106), the power supply interface of the brushless DC motor (101, 102) is connected to the power supply interface of the electronic speed regulator (103, 104), the propeller (129, 130) is installed on the brushless DC motor (101, 102), and the control interfaces of the DC / DC converter (105, 106) and the electronic speed regulator (103, 104) are all connected to the main controller (127).

[0071] The temperature control system provided by the embodiment of the present invention comprises temperature sensors (125, 126) and air supply fans (123, 124). The temperature sensors (125, 126) are installed in the air flow channel of the fuel cell stack (107, 108), the air supply fans (123, 124) are installed at the air intake end of the fuel cell stack (107, 108), the power supply interface of the air supply fans (123, 124) is connected to the programmable DC power supply (128), and the control port of the air supply fans (123, 124) is connected to the main controller (127).

[0072] The hydrogen supply system provided by the embodiment of the present invention comprises a high-pressure hydrogen storage tank (115, 116), a pressure reducing valve (113, 114), an intake valve (111, 112), a hydrogen flow sensor (109, 110), a back pressure valve (121, 122), a pressure sensor (119, 120), and a purge valve (117, 118). The high-pressure hydrogen storage tank (115, 116), the pressure reducing valve (113, 114), and the intake valve (111, 112) are sequentially connected to the hydrogen intake end of the fuel cell stack through a hydrogen pipeline. The back pressure valve (121, 122), the pressure sensor (119, 120), and purge valves (117, 118) are sequentially connected to the hydrogen outlet end of the fuel cell stack; the hydrogen flow sensors (109, 110) are installed between the intake valves (111, 112) and the hydrogen inlet of the fuel cell stack, record the hydrogen usage flow and transmit the data thereof to the main controller (127); the pressure sensors (119, 120) are installed between the back pressure valves (121, 122) and the purge valves (117, 118), record the current pressure value at the hydrogen outlet and transmit the data thereof to the main controller (127); the hydrogen flow sensors (109, 110) are mass flow meters.

[0073] like Figures 2-3As shown, the electric heating control method of a multi-stack fuel cell system for aviation provided by an embodiment of the present invention includes the following steps:

[0074] S101, obtaining a current-optimal temperature reference curve of an air-cooled fuel cell stack under a current test environment based on an aviation multi-stack fuel cell system test platform;

[0075] S102, for the air-cooled fuel cell stack under the current test environment, opening the hydrogen pressure reducing valve, the air intake fan, adjusting the hydrogen intake valve, setting the operating current, and starting the operation of the air-cooled fuel cell stack;

[0076] S103, measuring the stack output current, the stack internal temperature, and the fan voltage according to the actual working conditions; converting the stack output current, the stack internal temperature, and the fan voltage into electrical signals through the voltage sensor, the current sensor, and the temperature sensor, and transmitting them to the main controller;

[0077] S104, processing by the main controller; according to the current-optimal temperature value reference curve fitted by S101, the optimal temperature value corresponding to the fuel cell stack when the stack outputs current under actual working conditions is obtained; according to the actual temperature value transmitted to the controller by the temperature sensor, the temperature difference between the optimal temperature and the actual temperature is calculated; the voltage value of the air intake fan is calculated by the fuzzy self-anti-disturbance method, and it is fed back to the air intake fan to realize thermal management of the aviation multi-stack fuel cell system experimental platform.

[0078] like Figure 4 As shown, the current-optimal temperature value reference curve acquisition in step S101 provided in the embodiment of the present invention includes the following steps:

[0079] Step 1-1: Turn on the programmable DC power supply, connect the fuel cell stack air intake fan and the main controller, turn on the intake fan to provide oxygen for the fuel cell stack reaction;

[0080] Step 1-2: Open the pressure reducing valve of the high-pressure hydrogen storage tank and adjust the hydrogen inlet valve to make the inlet pressure of the hydrogen inlet end of the fuel cell stack reach a suitable range to provide hydrogen for the fuel cell stack reaction;

[0081] Step 1-3: Adjust the electronic control system; set the fixed load operating current, perform the air-cooled fuel cell startup operation, start the fuel cell stack, and operate it stably under this operating condition for a period of time to fully activate its performance;

[0082] Step 1-4: The air intake fan is controlled by a PWM signal. By adjusting the fan's PWM signal to operate at the maximum speed, the PWM value is 100% at this time, so that the temperature inside the air-cooled fuel cell stack reaches a low and stable state. The PWM signal value is fixedly reduced, and each reduction value is △PWM. The △PWM is set to 5% to 10% according to the size of the fixed load current, so that the internal temperature of the air-cooled fuel cell stack slowly rises.

[0083] Step 1-5: If the output voltage of the air-cooled fuel cell stack is observed during the test, if the output voltage becomes lower than the output voltage corresponding to the previous PWM value, then stop reducing the PWM value. The internal temperature of the air-cooled fuel cell at the moment of maximum output voltage during the experiment is the optimal temperature value under the current fixed load current. When the load current is 20A, Figure 5 and Figure 6 The temperature change graph and output voltage graph shown;

[0084] Step 1-6: Set different fixed load currents, repeat steps 1-4 to 1-5, and obtain the reference temperature under different fixed load currents. Figure 7 The current-optimum temperature value reference curve is shown.

[0085] During the processing of step S104 provided by the embodiment of the present invention, the main controller detects the actual operating current value in real time. If the actual operating current value changes, calculation processing is performed according to steps S103 to S104 using the new actual operating current value.

[0086] like Figure 8 As shown, the fuzzy auto-disturbance rejection method in step S104 provided in the embodiment of the present invention includes the following steps:

[0087] In step 4-1, the expression of the active disturbance rejection tracking differentiator (TD) is:

[0088]

[0089] Where h0 represents the step size of the fst function, h represents the sampling period, r represents the tracking speed, V0 is the optimal temperature value corresponding to the current value, V1 and V2 are the output values ​​of the active disturbance rejection tracking differentiator (TD);

[0090] In step 4-2, the expression of the active disturbance rejection extended state observer (ESO) is:

[0091]

[0092] Among them, y represents the temperature value inside the stack at the current moment, δ represents the filter factor, which is a constant, α1 and α2 are nonlinear factors, which are fixed values, Z1, Z2, and Z3 represent the observed values ​​of the total disturbance of the system of the tracking signal of y, b represents the compensation factor, and β 01 , β 02 , β 03 is the parameter of the extended state observer, u represents the control quantity;

[0093] In step 4-3, the expression of the nonlinear state error feedback control rate (NLSEF) of the active disturbance rejection is:

[0094]

[0095] Among them, e represents the temperature difference between the current temperature value and the optimal temperature value, e c It is expressed as the rate of change of the temperature difference between the current temperature value and the optimal temperature value. V1 and V2 are derived from the active disturbance rejection tracking differentiator (TD). β1 and β2 are the nonlinear state error feedback NLSEF parameters.

[0096] Step 4-4, fuzzify the nonlinear state error feedback parameters of the ADRC. The membership function is a triangular membership function, and its fuzzy domain is selected as [-6, 6]. The basic domain of its input and output is:

[0097]

[0098] The fuzzy control tables are shown in Tables 1 and 2.

[0099] Table 1 Fuzzy control table of Δβ1

[0100]

[0101] Table 2 Fuzzy control table of Δβ2

[0102]

[0103] Among them, e represents the temperature difference between the current temperature value and the optimal temperature value, e c It is expressed as the rate of change of the temperature difference between the current temperature value and the optimal temperature value, Δβ1 and Δβ2 are expressed as the change values ​​of parameters β1 and β2,

[0104] Step 4-5, substitute the corrected Δβ1 and Δβ2 into the calculation formula: And update parameters β1 and β2.

[0105] From the above, it can be seen that the use of fuzzy logic to control the self-disturbance rejection nonlinear state error feedback NLSEF parameters β1 and β2 improves the temperature response speed of the system, reduces the adjustment time of the fuel cell thermal management, reduces the overshoot of the fuel cell temperature, and can effectively improve the output characteristics of the fuel cell stack.

[0106] Through an aviation multi-stack fuel cell system experimental platform and thermal management control strategy provided by an embodiment of the present invention, a fuel cell stack internal temperature control diagram is obtained when the load current increases from 15A to 20A under the fuzzy active disturbance rejection control method, as shown in FIG. Figure 9 shown.

[0107] 2. Application Examples: In order to demonstrate the creativity and technical value of the technical solution of the present invention, this section provides application examples of the claimed technical solution on specific products or related technologies.

[0108] like Figure 1 As shown, the aviation multi-stack fuel cell system experimental platform provided by the embodiment of the present invention is installed on an aluminum alloy profile frame, and is mainly composed of an electronic control system, a temperature control system, a hydrogen supply system, an exhaust system, an air-cooled fuel cell stack, a master controller, and a programmable DC power supply; the electronic control system is connected to a 6mm 2 The wires are connected to the power supply port of the fuel cell stack. The temperature control system contains a K-type temperature sensor, and the sensor probe is inserted in the air flow channel between the fuel cell units. The hydrogen supply system is connected to the hydrogen inlet of the fuel cell stack using a stainless steel pipe, and the purge valve is connected to the hydrogen exhaust outlet of the fuel cell stack. The main controller is respectively connected to the control interface and signal transmission interface of the electronic control system, temperature control system, and hydrogen supply system. The controller is divided into two sets. One set is a controller model composed of a controller model and a control algorithm model built in the RT-LAB real-time simulator, and the other set is a hardware control circuit built with DSP28335 as the main control chip. The control algorithm code is written into DSP28335 through CCS software.

[0109] The electronic control system provided in an embodiment of the present invention is installed on another aluminum alloy profile frame, including a 24V-72V DC / DC converter, a brushless DC motor electronic speed regulator, a brushless DC motor, and a propeller. The DC / DC converter is connected to the power supply interface of the fuel cell stack, the power supply interface of the electronic speed regulator is connected to the DC / DC converter, the brushless DC motor is connected to the electronic speed regulator, and the propeller is installed on the brushless DC motor and fixed to the profile frame with aluminum alloy angle iron and screws.

[0110] The hydrogen supply system provided by an embodiment of the present invention includes a 35MP pressure-resistant carbon fiber high-pressure hydrogen storage tank, a pressure reducing valve, an intake valve, an explosion-proof hydrogen flow sensor, a fuel cell back pressure valve, a gas flow pressure sensor, and a purge valve. These components are connected to the hydrogen inlet of the fuel cell in sequence. The hydrogen flow sensor is installed between the intake valve and the hydrogen inlet of the fuel cell stack, records the hydrogen usage flow rate and transmits the hydrogen flow data to the main controller. The pressure sensor is installed between the back pressure valve and the purge valve, records the current pressure value at the hydrogen outlet and transmits the data to the main controller.

[0111] 3. Evidence of the effects of the embodiments: The embodiments of the present invention have achieved some positive effects during the development or use process, and indeed have great advantages over the existing technology. The following content describes them with reference to the data, charts, etc. of the experimental process.

[0112] First, an experimental platform for a multi-stack fuel cell system for aviation was built to provide an experimental basis. A fuzzy control algorithm was designed to control the variable parameters in the self-disturbance rejection algorithm based on real-time feedback data. This solved the shortcoming of traditional control algorithms in existing technologies that it is difficult to determine parameters. It also improved the efficiency of the fuel cell, increased the response speed of the fuel cell, and shortened the time it takes for the fan to adjust the temperature, which is beneficial to extending the life of the fuel cell and improving its durability, and achieving fast, stable and efficient output of the aviation fuel cell aircraft platform.

[0113] It should be noted that the embodiments of the present invention can be implemented by hardware, software, or a combination of software and hardware. The hardware portion can be implemented using dedicated logic; the software portion can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. Those skilled in the art will appreciate that the above-mentioned devices and methods can be implemented using computer-executable instructions and / or contained in processor control code, for example, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The devices and modules of the present invention can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, or can be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0114] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

Claims

1. An electrical heating control method for a multi-stack fuel cell system for aviation, characterized in that: The electric heat control method of the aviation multi-stack fuel cell system includes: Construct an aviation multi-stack fuel cell system experimental platform and obtain a reference curve of current-optimal temperature under experimental conditions based on this experimental platform. In an air-cooled fuel cell system, based on actual operating conditions in different environments, the temperature value transmitted in real time by the temperature sensor installed in the fuel cell stack air flow path is processed through a control algorithm to control the voltage value transmitted to the fuel cell stack air intake fan by the main controller, thereby achieving temperature control of the fuel cell stack. The method for controlling the electric heat of a multi-stack fuel cell system for aviation includes the following steps: Step 1: Based on the dual-engine air-cooled fuel cell aircraft experimental platform, obtain a current-optimal temperature value reference curve of the air-cooled fuel cell stack under the current test environment; Step 2: For the air-cooled fuel cell stack under the current test environment, open the hydrogen pressure reducing valve, the air intake fan, adjust the hydrogen intake valve, set the operating current, and start the air-cooled fuel cell stack; Step 3: Measure the stack output current, stack temperature, and fan voltage according to the actual working conditions; convert the stack output current, stack temperature, and fan voltage into electrical signals through voltage sensors, current sensors, and temperature sensors, and transmit them to the main controller; Step 4: Processing by the master controller. Based on the current-optimal temperature reference curve fitted in step 1, the optimal temperature value corresponding to the fuel cell stack when the stack outputs current under actual operating conditions is obtained. Based on the actual temperature value transmitted to the controller by the temperature sensor, the temperature difference between the optimal temperature and the actual temperature is calculated. The intake fan voltage value is calculated using the fuzzy anti-disturbance method and fed back to the intake fan to achieve thermal management of the aviation multi-stack fuel cell system experimental platform. The fuzzy auto-disturbance rejection method in step 4 includes: (1) The expression of the active disturbance rejection tracking differentiator is: Where h0 represents the step size of the fst function, h represents the sampling period, r represents the tracking speed, and V0 is the optimal temperature value corresponding to the current value; (2) The expression of the ADRC extended state observer is: Among them, y represents the temperature value inside the stack at the current moment, Z1, Z2, and Z3 represent the observed values ​​of the total disturbance of the tracking signal of y, b represents the compensation factor, and β 01 , β 02 , β 03 is the extended state observer parameter; (3) The expression of the nonlinear state error feedback control rate of the ADRC is: Among them, V1 and V2 are derived from the active disturbance rejection tracking differentiator, and β1 and β2 are the nonlinear state error feedback NLSEF parameters; (4) Fuzzify the nonlinear state error feedback parameters of the ADRC, select the triangular membership function as the membership function, select the fuzzy domain, and design the basic domain of input and output and the fuzzy control table; Among them, the basic domain of input and output is: Among them, e represents the temperature difference between the current temperature value and the optimal temperature value, e c It is expressed as the rate of change of the temperature difference between the current temperature value and the optimal temperature value, and Δβ1 and Δβ2 are the change values ​​of parameters β1 and β2; (5) Substitute the corrected Δβ1 and Δβ2 into the calculation formula: And update parameters β1 and β2.

2. The method for controlling the electric heating of a multi-stack fuel cell system for aviation according to claim 1, wherein: The current-optimal temperature value reference curve acquisition in step 1 includes: (1) Turn on the programmable DC power supply, connect the fuel cell stack air intake fan and the main controller, turn on the intake fan to provide oxygen for the fuel cell stack reaction; (2) Open the pressure reducing valve of the high-pressure hydrogen storage tank and adjust the hydrogen inlet valve to make the inlet pressure of the hydrogen inlet end of the fuel cell stack reach a suitable range to provide hydrogen for the fuel cell stack reaction; (3) Adjusting the electronic control system; setting the fixed load operating current, performing the air-cooled fuel cell startup operation, causing the fuel cell stack to start operating, and operating stably for a period of time under the operating conditions to activate performance; (4) The air intake fan is controlled by a PWM signal. By adjusting the PWM signal of the fan so that it runs at the maximum speed, the PWM value is 100%; the temperature inside the air-cooled fuel cell stack reaches a low level of stable state, and the PWM signal value is fixedly reduced, and each reduction value is △PWM; according to the size of the fixed load working current, △PWM is set to 5-10%, so that the internal temperature of the air-cooled fuel cell stack rises slowly; (5) If the output voltage of the air-cooled fuel cell stack is observed during the test, if the output voltage becomes lower than the output voltage corresponding to the previous PWM value, then the PWM value is stopped from being reduced; during the experiment, the internal temperature value of the air-cooled fuel cell at the moment corresponding to the maximum output voltage is the optimal temperature value under the current fixed load condition, and the temperature change graph and output voltage graph when the load current is 20A are obtained; (6) Setting different fixed load working currents, repeating steps (1) to (5), obtaining reference temperatures under different fixed load working currents, and drawing a current-optimal temperature value reference curve.

3. The method for controlling the electric heating of a multi-stack fuel cell system for aviation according to claim 1, wherein: During the processing of the master controller in step 4, the actual operating current value is detected in real time. If the actual operating current value changes, the calculation and processing are performed according to steps 3 to 4 with the new actual operating current value.

4. An aviation multi-stack fuel cell system test platform for implementing the electrical and thermal control method for aviation multi-stack fuel cell systems according to any one of claims 1 to 3, characterized in that: The aviation multi-stack fuel cell system experimental platform includes: an electronic control system, a temperature control system, a hydrogen supply system, an exhaust system, an air-cooled fuel cell stack, a master controller, and a programmable DC power supply; Among them, the electronic control system is connected to the power supply interface of the fuel cell stack, the temperature control system is arranged on the fuel cell stack and connected to the air supply fan of the stack; the hydrogen supply system is connected to the hydrogen inlet of the fuel cell stack, and the exhaust system is connected to the hydrogen outlet of the fuel cell stack; the main controller is respectively connected to the control interfaces of the electronic control system, the temperature control system, and the hydrogen supply system, and a voltage sensor and a current sensor are arranged in the electronic control system, a temperature sensor is arranged in the temperature control system, and a flow sensor and a pressure sensor are arranged in the hydrogen supply system. The voltage sensor, current sensor, and temperature sensor all transmit the measured working parameters to the main controller.

5. The aviation multi-stack fuel cell system test platform as claimed in claim 4, characterized in that: The electronic control system includes a DC / DC converter, an electronic speed regulator, a brushless DC motor, and a propeller. The power supply interface of the DC / DC converter is connected to the power supply interface of the fuel cell stack, the power supply interface of the electronic speed regulator is connected to the power supply interface of the DC / DC converter, the power supply interface of the brushless DC motor is connected to the power supply interface of the electronic speed regulator, the propeller is installed on the brushless DC motor, and the control interfaces of the DC / DC converter and the electronic speed regulator are both connected to the main controller; The temperature control system includes a temperature sensor and an air supply fan. The temperature sensor is installed in the air flow channel of the fuel cell stack. The air supply fan is installed at the air inlet end of the fuel cell stack. The power supply interface of the air supply fan is connected to a programmable DC power supply. The control port of the air supply fan is connected to the main controller. The hydrogen supply system includes a high-pressure hydrogen storage tank, a pressure reducing valve, an intake valve, a hydrogen flow sensor, a back pressure valve, a pressure sensor, and a purge valve. The high-pressure hydrogen storage tank, the pressure reducing valve, and the intake valve are connected to the hydrogen inlet end of the fuel cell stack in sequence through a hydrogen pipeline. The back pressure valve, the pressure sensor, and the purge valve are connected to the hydrogen outlet end of the fuel cell stack in sequence. The hydrogen flow sensor is installed between the intake valve and the hydrogen inlet of the fuel cell stack to record the hydrogen usage flow and transmit the data thereof to the main controller. The pressure sensor is installed between the back pressure valve and the purge valve to record the current pressure value at the hydrogen outlet and transmit the data to the main controller. The hydrogen flow sensor is a mass flow meter.

6. A computer device, characterized in that: The computer device includes a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the electric thermal control method for a multi-stack fuel cell system for aviation as described in any one of claims 1 to 3.

7. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the steps of the method for controlling the electric heating of a multi-stack fuel cell system for aviation according to any one of claims 1 to 3.

8. An information data processing terminal, characterized in that: The information data processing terminal is used to implement the aviation multi-stack fuel cell system experimental platform as described in any one of claims 4 to 5.

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