An air-cooled fuel cell adaptive temperature and humidity control device and method

Abstract

The present invention provides an air-cooled fuel cell adaptive temperature and humidity control device and method, belonging to the field of new energy power generation technology, the control device includes a heat dissipation system, a data acquisition system, a gas heating device, a gas humidification device and a controller, the gas humidification device includes a temperature-controllable water tank and two sets of atomization devices located above and below the heat dissipation system and the stack, the gas heating device is located between the two atomization devices, and the controller controls the heat dissipation system, the gas heating device and the gas humidification device according to the signal collected by the data acquisition system. According to the real-time detected internal temperature signal of the stack and the humidity signal of the cathode inlet, the present invention realizes adaptive humidification and temperature rise and fall regulation inside the air-cooled fuel cell stack by arranging a gas heating device and an atomization device at the cathode inlet, so that it works in an efficient and safe temperature and humidity working range, so as to improve the output performance and service life of the stack.

Description

Technical Field

[0001] The present invention belongs to the technical field of renewable energy power generation, and in particular relates to an air-cooled fuel cell adaptive temperature and humidity control device and method. Background Art

[0002] In recent years, with the development of new energy technologies, proton exchange membrane fuel cells (PEMFCs) as a clean energy system have the advantages of high efficiency, long endurance, and zero emissions, and have great application potential in the fields of transportation, power generation, and drones. Proton exchange membrane fuel cells are divided into water-cooled and air-cooled types. Among them, air-cooled fuel cells do not require a complex auxiliary system (BOP) and can directly use the forced convection generated by a DC fan to deliver oxygen to the cathode end and take away the heat generated by the electrochemical reaction. Due to its simplified cooling system design and low mass, it has broad application prospects in the fields of drone power systems and small backup power systems.

[0003] During the operation of air-cooled proton exchange membrane fuel cells, the increase in temperature is conducive to improving the activity of electrochemical reactions, thereby improving the output performance of the stack. However, the temperature increase will also increase the saturated vapor pressure of water and accelerate the evaporation rate of water. When it exceeds a certain value, it will cause the membrane to dry out, causing the battery output performance to decrease. The cathode heat dissipation system of the air-cooled proton exchange membrane fuel cell not only provides the oxygen required for the electrochemical reaction for the PEMFC, but also needs to take away the heat of the internal reaction. The cathode heat dissipation system of the air-cooled fuel cell in the prior art only forms forced air convection through an axial flow fan. On the one hand, it maintains the temperature balance inside the stack. On the other hand, the change in the cathode heat dissipation air flow rate will affect the evaporation rate of water inside the stack, thereby affecting the water content of the proton exchange membrane. Therefore, the water and heat management of the air-cooled fuel cell are coupled with each other. In order to keep the fuel cell at a high working efficiency during the actual operation, it is usually necessary to control the temperature and humidity of the stack near the optimal range under the current density to ensure the highest power generation efficiency of the fuel cell. Finding a device that can improve the temperature and humidity control ability of the air-cooled fuel cell is more conducive to the formulation of the temperature and humidity control method and improve the working efficiency of the fuel cell. Summary of the invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention proposes an adaptive temperature and humidity control device and method for an air-cooled fuel cell, which enables the air-cooled fuel cell to operate in an efficient and safe temperature and humidity working range, thereby improving the output performance and service life of the fuel cell stack.

[0005] The specific technical solutions of the present invention are as follows:

[0006] An air-cooled fuel cell adaptive temperature and humidity control device, characterized in that it includes a heat dissipation system, a data acquisition system, a gas heating device, a gas humidification device and a controller;

[0007] The heat dissipation system is located at the cathode inlet of the air-cooled fuel cell stack to blow air thereto;

[0008] The gas humidification device includes an external temperature-controllable water tank, and two sets of atomization devices located above and below the heat dissipation system and the air-cooled fuel cell stack, the atomization device is composed of a connected water storage tank and an atomizer, the atomizers of the two atomization devices are placed opposite to each other, and the water storage tank is connected to the temperature-controllable water tank;

[0009] The gas heating device is located between the two atomizers to heat the air between them;

[0010] The data acquisition system includes a stack internal temperature sensor, a water tank temperature sensor, a stack current acquisition module and a cathode inlet humidity sensor;

[0011] The controller is connected to the heat dissipation system, the data acquisition system, the gas heating device, and the gas humidification device, and controls the heat dissipation system, the gas heating device, and the gas humidification device according to the signals collected by the data acquisition system to achieve adaptive temperature and humidity control.

[0012] Furthermore, the specific control process of the controller includes humidification control and temperature control;

[0013] When the humidity at the cathode inlet of the stack is lower than the reference humidity, humidification control is performed, specifically: first, the temperature of the controllable temperature water tank is controlled near the reference temperature, and the output power of the heat dissipation system is kept unchanged, and then the atomizer is turned on, and the working power of the atomizer is adjusted according to the difference between the humidity at the cathode inlet of the stack and the reference humidity, until the humidity at the cathode inlet of the stack reaches the reference humidity;

[0014] The temperature control is as follows: by comparing the internal temperature of the battery stack with the reference temperature, determining whether to perform temperature reduction control or temperature increase control;

[0015] If the temperature is lowered, the temperature of the temperature-controllable water tank is first controlled to be lower than the reference temperature, and then the atomizer is turned on. The working power of the atomizer is adjusted according to the difference between the internal temperature of the battery stack and the reference temperature until the internal temperature of the battery stack reaches the reference temperature.

[0016] If temperature rise control is used, first determine whether the load current density is lower than the preset current density. If so, turn on the gas heating device, adjust the working power of the gas heating device according to the difference between the internal temperature of the fuel cell stack and the reference temperature, and at the same time control the temperature of the temperature-controllable water tank to be higher than the internal temperature of the fuel cell stack. Turn on the atomizer and perform auxiliary heating at the lowest working power until the internal temperature of the fuel cell stack reaches the reference temperature. Otherwise, keep the fuel cell stack working normally and use its own heat generation to heat it to the reference temperature.

[0017] Furthermore, when the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is 50% to 100% of the reference humidity, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is 20% to 50% of the reference humidity, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is less than 20% of the reference humidity, the working power of the atomizer is adjusted to 30% of the rated power.

[0018] Furthermore, when the difference between the internal temperature of the fuel cell stack and the reference temperature is 20% to 100% of the reference temperature, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is 5% to 20% of the reference temperature, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is less than 5% of the reference temperature, the working power of the atomizer is adjusted to 30% of the rated power.

[0019] Furthermore, when the difference between the internal temperature of the fuel cell stack and the reference temperature is 20% to 100% of the reference temperature, the working power of the gas heating device is adjusted to 90% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is 5% to 20% of the reference temperature, the working power of the gas heating device is adjusted to 60% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is less than 5% of the reference temperature, the working power of the gas heating device is adjusted to 30% of the rated power.

[0020] Furthermore, the preset current density is 0.2A / cm 2 .

[0021] Furthermore, the heat dissipation system includes an axial flow fan.

[0022] Furthermore, the gas heating device is an electric heating strip or a PTC heater.

[0023] Furthermore, the material of the water storage tank is high molecular foam cotton with strong water absorption capacity.

[0024] Furthermore, the heat dissipation system is located at the cathode outlet of the air-cooled fuel cell stack to absorb air, and the atomizing device in the gas humidifying device is located at the cathode inlet of the air-cooled fuel cell stack.

[0025] The present invention also proposes a control method based on the above air-cooled fuel cell adaptive temperature and humidity control device, which is characterized by including humidification control and temperature control;

[0026] The humidification control specifically comprises the following steps:

[0027] Step A1: obtaining a reference humidity trajectory during the operation of an air-cooled fuel cell stack and storing it in a controller;

[0028] Step A2: The controller determines whether the humidity data detected by the cathode inlet humidity sensor under the current operating current is lower than the corresponding reference humidity according to the current detected by the stack current acquisition module. If so, the controller proceeds to step A3; otherwise, the controller proceeds to step A6;

[0029] Step A3: The controller controls the temperature of the temperature-controllable water tank to be near the reference temperature according to the temperature data detected by the water tank temperature sensor, and controls the output power of the heat dissipation system to meet the air flow demand of its current state;

[0030] Step A4: the controller turns on the atomizer and adjusts the working power of the atomizer according to the difference between the humidity at the cathode inlet of the fuel cell stack and the reference humidity;

[0031] Step A5: The controller determines whether the current humidity at the cathode inlet of the battery stack reaches the reference humidity. If so, the current operating power of the atomizer is kept unchanged and the process goes to step A6; otherwise, the process goes back to step A4;

[0032] Step A6: Keep the current operating state of the fuel cell stack and continue to operate, and return to step A2 until the air-cooled fuel cell stack stops operating;

[0033] The temperature control specifically comprises the following steps:

[0034] Step B1: obtaining a reference temperature trajectory during the operation of an air-cooled fuel cell stack and storing it in a controller;

[0035] Step B2: The controller determines whether the internal temperature of the battery stack detected by the internal temperature sensor of the battery stack under the current operating current is higher than the corresponding reference temperature according to the current detected by the battery stack current acquisition module. If so, go to step B3; otherwise, go to step B4;

[0036] Step B3: This is the cooling control process, which specifically includes:

[0037] Step B31: the controller keeps the gas heating device turned off, and controls the temperature of the temperature-controllable water tank to be lower than the reference temperature according to the temperature data detected by the water tank temperature sensor;

[0038] Step B32: the controller turns on the atomizer and adjusts the working power of the atomizer according to the difference between the internal temperature of the fuel cell stack and the reference temperature;

[0039] Step B33: The controller determines whether the current internal temperature of the fuel cell stack has stably reached the reference temperature. If so, the current operating power of the atomizer is kept unchanged until the air-cooled fuel cell stack stops running; otherwise, the controller returns to step B31;

[0040] Step B4: This is the temperature rise control process, which specifically includes:

[0041] Step B41: the controller determines whether the stack output current density detected by the stack current acquisition module is lower than the preset current density. If so, the controller goes to step B42; otherwise, the controller goes to step B44;

[0042] Step B42: The controller turns on the gas heating device, adjusts the working power of the gas heating device according to the difference between the internal temperature of the fuel cell stack and the reference temperature, controls the temperature of the temperature-controllable water tank to be higher than the internal temperature of the fuel cell stack, turns on the atomizer, and performs auxiliary heating at the lowest working power;

[0043] Step B43: the controller determines whether the current internal temperature of the fuel cell stack reaches the reference temperature. If so, the current working power of the gas heating device is kept unchanged until the air-cooled fuel cell stack stops running; otherwise, the controller returns to step B42;

[0044] Step B44: Keep the battery stack operating normally and use its own heat to raise the temperature to the reference temperature.

[0045] The beneficial effects of the present invention are:

[0046] The present invention proposes an adaptive temperature and humidity control device and method for an air-cooled fuel cell. According to the real-time detected internal temperature signal of the fuel cell stack and the humidity signal of the cathode inlet, a gas heating device and an atomization device are arranged at the cathode inlet to realize adaptive temperature and humidity adjustment inside the air-cooled fuel cell stack, so that the stack can operate in an efficient and safe temperature and humidity working range, thereby improving the output performance and service life of the fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The internal temperature variation curve of the space-cooled fuel cell stack when the load current value is 20A in Example 1 of the present invention;

[0048] Figure 2 This is a schematic diagram of the structure of the air-cooled fuel cell adaptive temperature and humidity control device in Example 1 of the present invention;

[0049] Figure 3 This is a schematic diagram of the structure of the adaptive temperature and humidity control device for an air-cooled fuel cell in Example 2 of the present invention;

[0050] Figure 4 This is a flow chart of humidification control in Example 1 of the present invention;

[0051] Figure 5 This is a flow chart of temperature control in Example 1 of the present invention;

[0052] The meanings of the symbols in the accompanying drawings are as follows:

[0053] 11. Cathode inlet humidity sensor; 12. Stack internal temperature sensor; 13. Stack current acquisition module; 14. Water tank temperature sensor; 2. Air-cooled fuel cell stack; 3. Gas heating device; 41. Ultrasonic atomizer; 42. Water storage tank; 43. Controllable temperature water tank; 5. Cooling system. DETAILED DESCRIPTION

[0054] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in conjunction with the following specific embodiments and with reference to the accompanying drawings.

[0055] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0056] Example 1

[0057] This embodiment proposes an air-cooled fuel cell adaptive temperature and humidity control device, the structure of which is as follows: Figure 2 As shown, it includes a heat dissipation system 5, a data acquisition system, a gas heating device 3, a gas humidification device and a controller;

[0058] The heat dissipation system 5 is composed of two axial flow fans, which are located at the cathode inlet of the air-cooled fuel cell stack 2 to blow air thereto;

[0059] The gas humidifying device includes an external temperature-controlled water tank 43, and two sets of atomizing devices located above and below the heat dissipation system 5 and the air-cooled fuel cell stack 2. The atomizing device is composed of a connected water storage tank 42 and an ultrasonic atomizer 41. The ultrasonic atomizers 41 of the two atomizing devices are placed opposite to each other, and the water storage tank 42 is connected to the temperature-controlled water tank 43. The water storage tank 42 is made of high molecular foam cotton with strong water absorption capacity.

[0060] The gas heating device 3 is an electric heating strip, which is located between the two ultrasonic atomizers 41 to heat the air between them;

[0061] The data acquisition system includes a stack internal temperature sensor 12, a water tank temperature sensor 14, a stack current acquisition module 13 and a cathode inlet humidity sensor 11;

[0062] The controller is connected to the heat dissipation system 5, the data acquisition system, the gas heating device 3, and the gas humidification device. The heat dissipation system 5, the gas heating device 3, and the gas humidification device are controlled according to the signals collected by the data acquisition system to achieve adaptive temperature and humidity control. The specific control process includes humidification control and temperature control.

[0063] When the humidity at the cathode inlet of the battery stack is lower than the reference humidity, humidification control is performed, specifically: first, the temperature of the controllable temperature water tank 43 is controlled near the reference temperature, and the output power of the heat dissipation system 5 is kept unchanged, and then the ultrasonic atomizer 41 is turned on, and the working power of the ultrasonic atomizer 41 is adjusted according to the difference between the humidity at the cathode inlet of the battery stack and the reference humidity, until the humidity at the cathode inlet of the battery stack reaches the reference humidity; wherein, the specific adjustment process of the working power of the ultrasonic atomizer 41 is: when the difference between the humidity at the cathode inlet of the battery stack and the reference humidity is 50% to 100% of the reference humidity, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the humidity at the cathode inlet of the battery stack and the reference humidity is 20% to 50% of the reference humidity, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the humidity at the cathode inlet of the battery stack and the reference humidity is less than 20% of the reference humidity, the working power of the atomizer is adjusted to 30% of the rated power.

[0064] The temperature control is as follows: by comparing the internal temperature of the battery stack with the reference temperature, determining whether to perform temperature reduction control or temperature increase control;

[0065] If cooling control is used, the temperature of the controllable temperature water tank 43 is first controlled to be lower than the reference temperature, and then the ultrasonic atomizer 41 is turned on, and the working power of the ultrasonic atomizer 41 is adjusted according to the difference between the internal temperature of the battery stack and the reference temperature, until the internal temperature of the battery stack reaches the reference temperature; wherein, the specific adjustment process of the working power of the ultrasonic atomizer 41 is: when the difference between the internal temperature of the battery stack and the reference temperature is 20% to 100% of the reference temperature, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is 5% to 20% of the reference temperature, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is less than 5% of the reference temperature, the working power of the atomizer is adjusted to 30% of the rated power.

[0066] If the temperature is controlled, first determine whether the load current density is lower than the preset current density. If so, turn on the gas heating device 3, adjust the working power of the gas heating device 3 according to the difference between the internal temperature of the battery stack and the reference temperature, and at the same time control the temperature of the controllable temperature water tank to be higher than the internal temperature of the battery stack, turn on the ultrasonic atomizer 41, and perform auxiliary heating at the minimum working power until the internal temperature of the battery stack reaches the reference temperature; otherwise, keep the battery stack working normally and use its own heat generation to heat up to the reference temperature; wherein, the specific adjustment process of the working power of the gas heating device 3 is: when the difference between the internal temperature of the battery stack and the reference temperature is 20% to 100% of the reference temperature, adjust the working power of the gas heating device to 90% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is 5% to 20% of the reference temperature, adjust the working power of the gas heating device to 60% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is less than 5% of the reference temperature, adjust the working power of the gas heating device to 30% of the rated power.

[0067] This embodiment also proposes a control method based on the above air-cooled fuel cell adaptive temperature and humidity control device, including humidification control and temperature control;

[0068] like Figure 4 As shown, the humidification control specifically includes the following steps:

[0069] Step A1: Initialize the controller, obtain the reference humidity trajectory during the operation of the air-cooled fuel cell stack 2, and store it in the controller;

[0070] Step A2: the stack internal temperature sensor 12 collects the stack internal temperature of the air-cooled fuel cell stack 2, the cathode inlet humidity sensor 11 collects the cathode inlet humidity of the air-cooled fuel cell stack 2, the stack current acquisition module 13 collects the output current of the air-cooled fuel cell stack 2, and the water tank temperature sensor 14 detects the water tank temperature of the controllable temperature water tank 43; the controller determines whether the cathode inlet humidity is lower than the corresponding reference humidity under the current operating current according to the detected output current, and if so, proceeds to step A3; otherwise, proceeds to step A6;

[0071] Step A3: The controller controls the temperature of the temperature-controllable water tank 43 to be near the reference temperature according to the temperature data detected by the water tank temperature sensor 14, and controls the output power of the heat dissipation system 5 to meet the air flow demand of the current fuel cell stack operation state;

[0072] Step A4: the controller turns on the ultrasonic atomizer 41 and adjusts the working power of the ultrasonic atomizer 41 according to the difference between the humidity at the cathode inlet of the battery stack and the reference humidity;

[0073] Step A5: The controller determines whether the current humidity at the cathode inlet of the battery stack reaches the reference humidity. If so, the current working power of the ultrasonic atomizer 41 is kept unchanged and the process goes to step A6; otherwise, the process goes back to step A4;

[0074] Step A6: Keep the current operating state of the fuel cell stack and continue to operate, and return to step A2 until the air-cooled fuel cell stack 2 stops operating.

[0075] The temperature control specifically comprises the following steps:

[0076] Step B1: Initialize the controller, obtain the reference temperature trajectory during the operation of the air-cooled fuel cell stack 2, and store it in the controller;

[0077] Step B2: the stack internal temperature sensor 12 collects the stack internal temperature of the air-cooled fuel cell stack 2, the cathode inlet humidity sensor 11 collects the cathode inlet humidity of the air-cooled fuel cell stack 2, the stack current acquisition module 13 collects the output current of the air-cooled fuel cell stack 2, and the water tank temperature sensor 14 detects the water tank temperature of the temperature-controllable water tank 43; the controller determines whether the stack internal temperature exceeds the corresponding reference temperature under the current operating current according to the detected output current, and if so, goes to step B3; otherwise, goes to step B4;

[0078] Step B3: This is the cooling control process, such as Figure 5 As shown, specifically including:

[0079] Step B31: the controller keeps the gas heating device 3 turned off, and controls the temperature of the temperature-controllable water tank 43 to be lower than the reference temperature according to the temperature data detected by the water tank temperature sensor 14;

[0080] Step B32: the controller turns on the ultrasonic atomizer 41 and adjusts the working power of the ultrasonic atomizer 41 according to the difference between the internal temperature of the fuel cell stack and the reference temperature;

[0081] Step B33: the controller determines whether the current internal temperature of the fuel cell stack reaches the reference temperature. If so, the current working power of the ultrasonic atomizer 41 is kept unchanged until the air-cooled fuel cell stack 2 stops running; otherwise, the controller returns to step B31;

[0082] Step B4: This is the temperature rise control process, such as Figure 5 As shown, specifically including:

[0083] Step B41: The controller determines whether the current density of the battery stack output is lower than the preset current density. If so, the process goes to step B42; otherwise, the process goes to step B44;

[0084] Step B42: the controller turns on the gas heating device 3, adjusts the working power of the gas heating device 3 according to the difference between the internal temperature of the fuel cell stack and the reference temperature, controls the temperature of the temperature-controllable water tank to be higher than the internal temperature of the fuel cell stack, turns on the ultrasonic atomizer 41, and performs auxiliary heating at the lowest working power;

[0085] Step B43: the controller determines whether the current internal temperature of the fuel cell stack reaches the reference temperature. If so, the current working power of the gas heating device is kept unchanged until the air-cooled fuel cell stack 2 stops running; otherwise, the controller returns to step B42;

[0086] Step B44: Keep the battery stack operating normally and use its own heat to raise the temperature to the reference temperature.

[0087] The above control method is described below with a specific example:

[0088] The humidification control specifically comprises the following steps:

[0089] Step A1: Obtain the reference humidity trajectory during the operation of the air-cooled fuel cell stack 2 and store it in the controller. When the load current value is 20A, the reference humidity 90%;

[0090] Step A2: The controller determines the humidity data detected by the cathode inlet humidity sensor 11 under the current running current according to the 20A current detected by the battery stack current acquisition module 13. Is it lower than the corresponding reference humidity? If yes, go to step A3; otherwise, go to step A6;

[0091] Step A3: The controller controls the temperature of the temperature-controllable water tank 43 at a reference temperature T according to the temperature data detected by the water tank temperature sensor 14. ref Nearby, and keep the output power of the heat dissipation system 5 unchanged, specifically set the fan speed PWM of the axial flow fan to be fixed at 40%;

[0092] Step A4: The controller turns on the ultrasonic atomizer 41. If the humidity at the cathode inlet of the stack is The humidity at the cathode inlet of the stack is calculated to be 70%. With reference humidity The difference is 20%, accounting for the reference humidity 22.2%, which is in the range of 20% to 50%, so the ultrasonic atomizer 41 is controlled to work at 60% of its rated power;

[0093] Step A5: The controller determines the current humidity at the cathode inlet of the stack Whether the reference humidity is reached If yes, keep the current working power of the ultrasonic atomizer 41 unchanged and go to step A6; otherwise, go back to step A4;

[0094] Step A6: Keep the current operating state of the fuel cell stack and continue to operate, and return to step A2 until the air-cooled fuel cell stack 2 stops operating.

[0095] The temperature control specifically comprises the following steps:

[0096] Step B1: Obtain the reference temperature trajectory during the operation of the air-cooled fuel cell stack 2 and store it in the controller; wherein the internal temperature change curve of the air-cooled fuel cell stack 2 when the load current value is 20A is as follows: Figure 1 As shown, the reference temperature T ref 42℃;

[0097] Step B2: The controller determines the internal temperature T of the stack detected by the internal temperature sensor 12 of the stack under the current operating current according to the 20A current detected by the stack current acquisition module 13. st Whether it exceeds the corresponding reference temperature T ref , if yes, go to step B3; otherwise, go to step B4;

[0098] Step B3: If the internal temperature of the battery stack is T st The temperature is 46.6℃, which is the cooling control process, including:

[0099] Step B31: the controller keeps the gas heating device 3 turned off, and controls the temperature of the temperature-controllable water tank 43 to be lower than the reference temperature according to the temperature data detected by the water tank temperature sensor 14;

[0100] Step B32: The controller turns on the ultrasonic atomizer 41 and calculates the internal temperature of the stack T st With reference temperature T ref The difference is 4.6℃, accounting for the reference temperature T ref 10.95%, which is in the range of 5% to 20%, so the ultrasonic atomizer 41 is controlled to work at 60% of its rated power;

[0101] Step B33: The controller determines the current internal temperature of the stack T st Whether the reference temperature T is reached stably ref If yes, then keep the current working power of the ultrasonic atomizer 41 unchanged until the air-cooled fuel cell stack 2 stops running; otherwise, return to step B31;

[0102] Step B4: If the internal temperature of the battery stack is T st The temperature is 39.92℃, which is the temperature rise control process, including:

[0103] Step B41: The controller determines whether the stack output current density is lower than the preset current density of 0.2A / cm 2 , if yes, go to step B42; otherwise, go to step B44;

[0104] Step B42: The controller turns on the gas heating device 3 and calculates the internal temperature of the stack T st With reference temperature T ref The difference is 2.08℃, accounting for the reference temperature T ref 5.21%, which is in the range of 5% to 20%, so the gas heating device 3 is controlled to work at 60% of its rated power; at the same time, the temperature of the controllable temperature water tank is controlled to be higher than the internal temperature T of the fuel cell stack. st , turn on the ultrasonic atomizer 41 to assist in heating at the lowest working power;

[0105] Step B43: The controller determines the current internal temperature of the stack T st Whether the reference temperature T is reached ref If yes, then keep the working power of the current gas heating device unchanged until the air-cooled fuel cell stack 2 stops running; otherwise, return to step B42;

[0106] Step B44: Keep the battery stack operating normally and use its own heat to raise the temperature to the reference temperature.

[0107] Example 2

[0108] This embodiment proposes an air-cooled fuel cell adaptive temperature and humidity control device, the structure of which is as follows: Figure 3 As shown, it includes a heat dissipation system 5, a data acquisition system, a gas heating device 3, a gas humidifying device and a controller; compared with Example 1, the only difference is: the position of the heat dissipation system 5 is adjusted to the cathode outlet of the air-cooled fuel cell stack 2, and air is sucked therefrom. At this time, the atomizing device in the gas humidifying device is located at the cathode inlet of the air-cooled fuel cell stack 2; other structures remain unchanged.

[0109] This embodiment also proposes a control method based on the above-mentioned air-cooled fuel cell adaptive temperature and humidity control device, which is the same as that of Embodiment 1.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the embodiments, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. An air-cooled fuel cell adaptive temperature and humidity control device, characterized in that: It includes a heat dissipation system, a data acquisition system, a gas heating device, a gas humidification device and a controller; The heat dissipation system is located at the cathode inlet of the air-cooled fuel cell stack to blow air thereto; The gas humidification device includes an external temperature-controllable water tank, and two sets of atomization devices located above and below the heat dissipation system and the air-cooled fuel cell stack, the atomization device is composed of a connected water storage tank and an atomizer, the atomizers of the two atomization devices are placed opposite to each other, and the water storage tank is connected to the temperature-controllable water tank; The gas heating device is located between the two atomizers; The data acquisition system includes a stack internal temperature sensor, a water tank temperature sensor, a stack current acquisition module and a cathode inlet humidity sensor; The controller is connected to the heat dissipation system, the data acquisition system, the gas heating device, and the gas humidification device, and controls the heat dissipation system, the gas heating device, and the gas humidification device according to the signals collected by the data acquisition system to achieve adaptive temperature and humidity control; The control process of the controller includes humidification control and temperature control; When the humidity at the cathode inlet of the stack is lower than the reference humidity, humidification control is performed, specifically: first, the temperature of the controllable temperature water tank is controlled near the reference temperature, and the output power of the heat dissipation system is kept unchanged, and then the atomizer is turned on, and the working power of the atomizer is adjusted according to the difference between the humidity at the cathode inlet of the stack and the reference humidity, until the humidity at the cathode inlet of the stack reaches the reference humidity; The temperature control is as follows: by comparing the internal temperature of the battery stack with the reference temperature, determining whether to perform temperature reduction control or temperature increase control; If the temperature is lowered, the temperature of the temperature-controllable water tank is first controlled to be lower than the reference temperature, and then the atomizer is turned on. The working power of the atomizer is adjusted according to the difference between the internal temperature of the battery stack and the reference temperature until the internal temperature of the battery stack reaches the reference temperature. If temperature rise control is used, first determine whether the load current density is lower than the preset current density. If so, turn on the gas heating device, adjust the working power of the gas heating device according to the difference between the internal temperature of the fuel cell stack and the reference temperature, and at the same time control the temperature of the temperature-controllable water tank to be higher than the internal temperature of the fuel cell stack. Turn on the atomizer and perform auxiliary heating at the lowest working power until the internal temperature of the fuel cell stack reaches the reference temperature. Otherwise, keep the fuel cell stack working normally and use its own heat generation to heat it to the reference temperature.

2. The air-cooled fuel cell adaptive temperature and humidity control device according to claim 1, characterized in that: When the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is 50% to 100% of the reference humidity, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is 20% to 50% of the reference humidity, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the cathode inlet humidity of the fuel cell stack and the reference humidity is less than 20% of the reference humidity, the working power of the atomizer is adjusted to 30% of the rated power.

3. The air-cooled fuel cell adaptive temperature and humidity control device according to claim 1, characterized in that: When the difference between the internal temperature of the battery stack and the reference temperature is 20% to 100% of the reference temperature, the working power of the atomizer is adjusted to 90% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is 5% to 20% of the reference temperature, the working power of the atomizer is adjusted to 60% of the rated power; when the difference between the internal temperature of the battery stack and the reference temperature is less than 5% of the reference temperature, the working power of the atomizer is adjusted to 30% of the rated power.

4. The air-cooled fuel cell adaptive temperature and humidity control device according to claim 1, characterized in that: When the difference between the internal temperature of the fuel cell stack and the reference temperature is 20% to 100% of the reference temperature, the working power of the gas heating device is adjusted to 90% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is 5% to 20% of the reference temperature, the working power of the gas heating device is adjusted to 60% of the rated power; when the difference between the internal temperature of the fuel cell stack and the reference temperature is less than 5% of the reference temperature, the working power of the gas heating device is adjusted to 30% of the rated power.

5. The air-cooled fuel cell adaptive temperature and humidity control device according to claim 1, characterized in that: The heat dissipation system is located at the cathode outlet of the air-cooled fuel cell stack to absorb air. At this time, the atomizing device in the gas humidifying device is located at the cathode inlet of the air-cooled fuel cell stack.

6. A control method based on the air-cooled fuel cell adaptive temperature and humidity control device according to any one of claims 1 to 5, characterized in that: Including humidification control and temperature control; The humidification control specifically comprises the following steps: Step A1: obtaining a reference humidity trajectory during the operation of an air-cooled fuel cell stack and storing it in a controller; Step A2: The controller determines whether the cathode inlet humidity under the current stack current is lower than the corresponding reference humidity according to the detected stack current. If so, the process proceeds to step A3; otherwise, the process proceeds to step A6; Step A3: The controller controls the temperature of the temperature-controllable water tank to be near the reference temperature, and controls the output power of the heat dissipation system to remain unchanged; Step A4: the controller turns on the atomizer and adjusts the working power of the atomizer according to the difference between the humidity at the cathode inlet of the fuel cell stack and the reference humidity; Step A5: The controller determines whether the current humidity at the cathode inlet of the battery stack reaches the reference humidity. If so, the current operating power of the atomizer is kept unchanged and the process goes to step A6; otherwise, the process goes back to step A4; Step A6: Keep the current operating state of the fuel cell stack and continue to operate, and return to step A2 until the air-cooled fuel cell stack stops operating; The temperature control specifically comprises the following steps: Step B1: obtaining a reference temperature trajectory during the operation of an air-cooled fuel cell stack and storing it in a controller; Step B2: The controller determines whether the internal temperature of the battery stack under the current battery stack current is higher than the corresponding reference temperature according to the detected battery stack current. If so, the controller goes to step B3; otherwise, the controller goes to step B4; Step B3: This is the cooling control process, which specifically includes: Step B31: the controller keeps the gas heating device turned off and controls the temperature of the temperature-controllable water tank to be lower than the reference temperature; Step B32: the controller turns on the atomizer and adjusts the working power of the atomizer according to the difference between the internal temperature of the fuel cell stack and the reference temperature; Step B33: The controller determines whether the current internal temperature of the fuel cell stack has stably reached the reference temperature. If so, the current operating power of the atomizer is kept unchanged until the air-cooled fuel cell stack stops running; otherwise, the controller returns to step B31; Step B4: This is the temperature rise control process, which specifically includes: Step B41: The controller determines whether the detected stack output current density is lower than the preset current density. If so, the process goes to step B42; otherwise, the process goes to step B44; Step B42: The controller turns on the gas heating device, adjusts the working power of the gas heating device according to the difference between the internal temperature of the fuel cell stack and the reference temperature, controls the temperature of the temperature-controllable water tank to be higher than the internal temperature of the fuel cell stack, turns on the atomizer, and performs auxiliary heating at the lowest working power; Step B43: the controller determines whether the current internal temperature of the fuel cell stack reaches the reference temperature. If so, the current working power of the gas heating device is kept unchanged until the air-cooled fuel cell stack stops running; otherwise, the controller returns to step B42; Step B44: Keep the battery stack operating normally and use its own heat to raise the temperature to the reference temperature.

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