A control method and device for electronic thermostat and a fuel cell thermal management system

Abstract

The present invention relates to the field of fuel cell technology, and specifically discloses a control method and device for an electronic thermostat and a fuel cell thermal management system. The control method for the electronic thermostat includes: obtaining the coolant temperature at the outlet of the stack, the coolant temperature at the inlet of the stack, the coolant temperature at the outlet of the radiator, the ambient temperature, and the output power of the stack in real time; calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the outlet of the stack, the ambient temperature, and the output power of the stack; determining the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the coolant temperature at the outlet of the stack, the coolant temperature at the inlet of the stack, and the coolant temperature at the outlet of the radiator, and controlling the electronic thermostat to execute the target opening. The control method for the electronic thermostat provided by the present invention can quickly complete the mixing of large and small circulating coolants while reducing the temperature fluctuation of the stack through the control of the target opening of the electronic thermostat, which is beneficial to the improvement of the power generation efficiency of the stack.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a control method of an electronic thermostat, a control device of an electronic thermostat and a fuel cell thermal management system. Background Art

[0002] The suitable operating temperature of proton exchange membrane fuel cells is generally 60℃~80℃. At present, most fuel cell thermal management systems adopt the design of large and small cycles, setting a small cycle to quickly increase the temperature of the stack and improve the activity of the catalyst; setting a large cycle to dissipate heat to maintain the stack at the optimal temperature. In the application process of this solution, there is a temperature control stage in which high and low temperature coolants are mixed. By adjusting the opening of the electronic thermostat and allocating the proportion of high and low temperature coolants entering the stack, the inlet temperature of the stack is kept in a relatively stable state.

[0003] The existing technology generally adopts an open-loop control method with set upper and lower limits of temperature, which has problems such as frequent start and stop of components related to the stack cooling system and large fluctuations in stack temperature. In addition, due to the slow change of coolant temperature, the use of PID closed-loop control has the problem of obvious lag in water temperature control. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a control method for an electronic thermostat, a control device for an electronic thermostat and a fuel cell thermal management system, aiming to achieve a smooth transition of the coolant temperature at the inlet of the fuel cell stack during the mixing of large and small cycles.

[0005] As a first aspect of the present invention, a control method for an electronic thermostat is provided, the control method for the electronic thermostat comprising:

[0006] Step S1: acquiring in real time the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature and the stack output power;

[0007] Step S2: Calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power;

[0008] Step S3: determining the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the stack outlet coolant temperature, the stack inlet coolant temperature and the radiator outlet coolant temperature, and controlling the electronic thermostat to execute the target opening.

[0009] Further, the target opening control enabling of the electronic thermostat is calculated according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power, and further includes:

[0010] Step S21: start;

[0011] Step S22: determine whether the current stack outlet coolant temperature is greater than or equal to the second temperature limit value; if so, execute step S23; if not, execute step S25;

[0012] Step S23: querying the minimum output power curve of the battery stack according to the current ambient temperature to obtain the lower limit value of the battery stack output power when the electronic thermostat is turned on;

[0013] Step S24: determine whether the current stack output power is greater than or equal to the stack output power lower limit value when the electronic thermostat is turned on; if so, execute step S26; if not, execute step S25;

[0014] Step S25: Determine whether the current stack outlet coolant temperature is less than or equal to the first temperature limit value; if so, execute step S28; if not, execute step S27;

[0015] Step S26: setting the target opening control enable of the electronic thermostat to 1;

[0016] Step S27: setting the target opening control enable of the electronic thermostat to 2;

[0017] Step S28: setting the target opening control enable of the electronic thermostat to 0.

[0018] Further, the target opening of the electronic thermostat is determined according to the target opening control enable of the electronic thermostat, the stack outlet coolant temperature, the stack inlet coolant temperature and the radiator outlet coolant temperature, and further includes:

[0019] Step S31: when the target opening control enable of the electronic thermostat is set to 0, the target opening of the electronic thermostat is controlled to be zero;

[0020] Step S32: when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic;

[0021] Step S33: When the target opening control enable of the electronic thermostat is set to 2, the target opening of the electronic thermostat is controlled to be frozen and maintain the value at the last moment.

[0022] Further, when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic, wherein the calculation process of the target opening of the electronic thermostat is divided into four stages, namely, the first stage step S321, the second stage step S322, the third stage step S323 and the fourth stage step S324, specifically including:

[0023] Step S321: when the coolant temperature at the outlet of the stack rises to the second temperature limit value, the target opening of the electronic thermostat is calculated to be the first opening according to the preset logic, and the electronic thermostat is controlled to execute the first opening; wherein, during the process of the electronic thermostat executing the first opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the third temperature limit value, the control completion mark position of the first stage of the electronic thermostat is set to 1;

[0024] Step S322: when the control completion mark position of the first stage of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be a second opening according to the preset logic, and the electronic thermostat is controlled to execute the second opening; wherein, during the process of the electronic thermostat executing the second opening, the temperature of the coolant at the inlet of the stack continues to rise, and the rate of change of the temperature of the coolant at the inlet of the stack continues to decrease;

[0025] When the rate of change of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be a third opening according to a preset logic, and the electronic thermostat is controlled to execute the third opening; wherein, during the process of the electronic thermostat executing the third opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to a fourth temperature limit value, the second stage control completion mark position of the electronic thermostat is set to 1;

[0026] Step S323: when the second stage control completion mark position of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be a fourth opening according to the preset logic, and the electronic thermostat is controlled to execute the fourth opening; wherein, during the process of the electronic thermostat executing the fourth opening, the temperature of the coolant at the inlet of the stack continues to rise, and the rate of change of the temperature of the coolant at the inlet of the stack continues to decrease;

[0027] When the rate of change of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be the fifth opening according to the preset logic, and the electronic thermostat is controlled to execute the fifth opening; wherein, during the process of the electronic thermostat executing the fifth opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the fifth temperature limit value, the control completion mark position of the third stage of the electronic thermostat is set to 1;

[0028] Step S324: when the third stage control completion mark position of the electronic thermostat is 1, determining whether the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value;

[0029] If the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value, determine whether the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet is less than or equal to the temperature difference threshold value; if the difference is less than or equal to the temperature difference threshold value, control the electronic thermostat to perform the maximum opening; if the difference is greater than the temperature difference threshold value, calculate the target opening of the electronic thermostat as the sixth opening according to the preset logic, and control the electronic thermostat to perform the sixth opening;

[0030] If the coolant temperature at the stack outlet is greater than the sixth temperature limit value, the electronic thermostat is controlled to perform the maximum opening.

[0031] Furthermore, when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic, and further includes:

[0032] When the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat in each stage is calculated using the preset formula (1), and the preset formula (1) is:

[0033]

[0034] in, Refers to the target opening of the electronic thermostat. Refers to the coolant flow in the small cycle, Refers to the coolant flow rate in the large cycle, + , Refers to the total coolant flow entering the stack through the electronic thermostat; Refers to the coolant temperature at the stack outlet. Refers to the coolant temperature at the radiator outlet. Refers to the target temperature of the coolant at the stack inlet.

[0035] Furthermore, the first stage step S321 further includes:

[0036] Step S3211: Detecting the coolant temperature at the stack outlet is greater than or equal to the second temperature limit value;

[0037] Step S3212: Setting the target temperature of the coolant at the stack inlet ,in, is the first expected temperature, and the target opening of the electronic thermostat is calculated by formula (1) as the first opening;

[0038] Step S3213: controlling the electronic thermostat to execute the first opening, and feeding back the current actual opening of the electronic thermostat;

[0039] Step S3214: Determine the coolant temperature at the stack outlet Is it greater than or equal to the third temperature limit value? If so, execute step S3215; if not, return to step S3213;

[0040] Step S3215: Set the first stage control completion flag position of the electronic thermostat to 1.

[0041] Furthermore, the second stage step S322 further includes:

[0042] Step S3221: Detecting that the first stage control completion mark position of the electronic thermostat is 1;

[0043] Step S3222: Look up the first preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain the second expected temperature ;

[0044] Step S3223: Setting the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a second opening;

[0045] Step S3224: controlling the electronic thermostat to execute the second opening, and feeding back the current actual opening of the electronic thermostat;

[0046] Step S3225: acquiring the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3226; if not, returning to step S3224;

[0047] Step S3226: Setting the target temperature of the coolant at the stack inlet ,in, is the third expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the third opening;

[0048] Step S3227: controlling the electronic thermostat to execute the third opening, and feeding back the current actual opening of the electronic thermostat;

[0049] Step S3228: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fourth temperature limit value? If so, execute step S3229; if not, return to step S3227;

[0050] Step S3229: Set the second stage control completion flag position of the electronic thermostat to 1.

[0051] Furthermore, the third stage step S323 further includes:

[0052] Step S3231: Detecting that the second stage control completion mark position of the electronic thermostat is 1;

[0053] Step S3232: Look up the second preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain a fourth expected temperature. ;

[0054] Step S3233: Setting the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a fourth opening;

[0055] Step S3234: controlling the electronic thermostat to execute the fourth opening, and feeding back the current actual opening of the electronic thermostat;

[0056] Step S3235: obtaining the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3236; if not, returning to executing step S3234;

[0057] Step S3236: Setting the target temperature of the coolant at the stack inlet ,in, is the fifth expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the fifth opening;

[0058] Step S3237: controlling the electronic thermostat to execute the fifth opening, and feeding back the current actual opening of the electronic thermostat;

[0059] Step S3238: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fifth temperature limit value? If so, execute step S3239; if not, return to execute step S3237;

[0060] Step S3239: Set the third stage control completion flag position of the electronic thermostat to 1.

[0061] Furthermore, the fourth stage step S324 further includes:

[0062] Step S3241: Detecting that the third stage control completion mark position of the electronic thermostat is 1;

[0063] Step S3242: Determine the coolant temperature at the stack outlet Is it less than or equal to the sixth temperature limit value? If so, execute step S3243; if not, execute step S3246;

[0064] Step S3243: Calculate the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet, and determine whether it is less than or equal to the temperature difference threshold; if so, execute step S3246; if not, execute step S3244;

[0065] Step S3244: Setting the target temperature of the coolant at the stack inlet ,in, is the sixth expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the sixth opening;

[0066] Step S3245: controlling the electronic thermostat to execute the sixth opening, and feeding back the current actual opening of the electronic thermostat;

[0067] Step S3246: Control the electronic thermostat to perform the maximum opening.

[0068] As another aspect of the present invention, a control device for an electronic thermostat is provided, which is used to implement the control method for the electronic thermostat described above, and the control device for the electronic thermostat comprises:

[0069] An acquisition module is used to obtain the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature and the stack output power in real time;

[0070] A calculation module, used for calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power;

[0071] A determination module is used to determine the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, and the coolant temperature at the radiator outlet, and control the electronic thermostat to execute the target opening.

[0072] As another aspect of the present invention, a fuel cell thermal management system is provided, comprising: a fuel cell stack, a first temperature sensor, a second temperature sensor, an electronic water pump, an electronic thermostat, a third temperature sensor, a radiator, a cooling fan, a fuel cell control unit, a voltage sensor, a current sensor and an ambient temperature sensor, wherein the fuel cell control unit is respectively connected to the first temperature sensor, the second temperature sensor, the electronic water pump, the electronic thermostat, the third temperature sensor, the cooling fan, the voltage sensor, the current sensor and the ambient temperature sensor through a wiring harness, wherein the fuel cell control unit comprises the control device of the electronic thermostat as described above, wherein the coolant at the outlet of the fuel cell stack is pumped by the electronic water pump, and one path flows through the electronic thermostat and is transported back to the inlet of the fuel cell stack, which is called a small cycle, and the coolant in the small cycle is a high-temperature coolant; the other path flows through the electronic thermostat after heat dissipation through the radiator and the cooling fan and is transported to the inlet of the fuel cell stack, which is called a large cycle, and the coolant in the large cycle is a low-temperature coolant; the fuel cell control unit controls the opening of the electronic thermostat to allocate the ratio of high-temperature coolant and low-temperature coolant entering the fuel cell stack;

[0073] The first temperature sensor is arranged at the outlet of the fuel cell stack to detect the coolant temperature at the outlet of the fuel cell stack; the second temperature sensor is arranged at the inlet of the fuel cell stack to detect the coolant temperature at the inlet of the fuel cell stack; the third temperature sensor is arranged at the outlet of the radiator to detect the coolant temperature at the outlet of the radiator; the ambient temperature sensor is used to detect the current ambient temperature; the voltage sensor is used to detect the output voltage of the fuel cell stack, and the current sensor is used to detect the output current of the fuel cell stack. The fuel cell control unit can calculate the output power of the fuel cell stack based on the output voltage and the output current of the fuel cell stack.

[0074] The control method of the electronic thermostat provided by the present invention has the following beneficial effects:

[0075] (1) Compared with pure open-loop upper and lower limit control, the temperature hysteresis range is set, and the current heat generation rate of the fuel cell stack and the ambient heat dissipation rate are comprehensively considered to avoid frequent opening and closing of the electronic thermostat, which causes drastic fluctuations in the coolant temperature at the fuel cell stack inlet;

[0076] (2) The electronic thermostat is opened in stages, alternating between a small opening and a large opening. By repeatedly opening the large opening to quickly mix the high and low temperature coolants, the temperature of the coolant at the inlet of the fuel cell stack only fluctuates slightly, and after each large opening, it switches to a small opening to further eliminate temperature fluctuations and achieve rapid and uniform heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation of the present invention.

[0078] Figure 1 The present invention provides a flow chart of a method for controlling an electronic thermostat.

[0079] Figure 2 A calculation flow chart for enabling target opening control of an electronic thermostat provided by the present invention.

[0080] Figure 3 A control flow chart of the target opening of the electronic thermostat provided by the present invention.

[0081] Figure 4 The present invention provides a specific calculation flow chart of the target opening of the electronic thermostat when the target opening control enable of the electronic thermostat is set to 1.

[0082] Figure 5 The present invention provides a flow chart for calculating the target opening of the electronic thermostat in the first stage.

[0083] Figure 6 The present invention provides a flow chart for calculating the target opening of the second-stage electronic thermostat.

[0084] Figure 7 The present invention provides a flow chart for calculating the target opening of the electronic thermostat in the third stage.

[0085] Figure 8 The present invention provides a flow chart for calculating the target opening of the electronic thermostat in the fourth stage.

[0086] Fig. 9 This is a structural diagram of the fuel cell thermal management system provided by the present invention. DETAILED DESCRIPTION

[0087] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0088] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0089] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the present invention described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0090] In this embodiment, a control method for an electronic thermostat is provided. Figure 1 As shown, the control method of the electronic thermostat includes:

[0091] Step S1: acquiring in real time the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature and the stack output power;

[0092] Step S2: Calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power;

[0093] Step S3: determining the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the stack outlet coolant temperature, the stack inlet coolant temperature and the radiator outlet coolant temperature, and controlling the electronic thermostat to execute the target opening.

[0094] It should be understood that when the opening of the electronic thermostat is 0, the coolant is transported to the entrance of the fuel cell stack through the small circulation; when the opening of the electronic thermostat is 100%, the coolant is transported to the entrance of the fuel cell stack through the large circulation; when the opening range of the electronic thermostat is (0, 100%), the coolant is transported to the entrance of the fuel cell stack through a mixture of the small circulation and the large circulation.

[0095] Preferably, if Figure 2 As shown, the target opening control enabling of the electronic thermostat is calculated according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power, and further includes:

[0096] Step S21: start;

[0097] Step S22: determine whether the current stack outlet coolant temperature is greater than or equal to a second temperature limit value, where the second temperature limit value is set to 60° C.; if so, execute step S23; if not, execute step S25;

[0098] Step S23: querying the minimum output power curve of the battery stack according to the current ambient temperature to obtain the lower limit value of the battery stack output power when the electronic thermostat is turned on;

[0099] Step S24: determine whether the current stack output power is greater than or equal to the lower limit of the stack output power when the electronic thermostat is turned on; if so, it means that the current stack heat generation rate is greater than the heat dissipation rate, and step S26 is executed; if not, it means that the current stack heat generation rate is less than the heat dissipation rate, and step S25 is executed;

[0100] Step S25: determine whether the current stack outlet coolant temperature is less than or equal to a first temperature limit value, where the first temperature limit value is set to 50° C.; if so, execute step S28; if not, execute step S27;

[0101] Step S26: setting the target opening control enable of the electronic thermostat to 1;

[0102] Step S27: setting the target opening control enable of the electronic thermostat to 2;

[0103] Step S28: setting the target opening control enable of the electronic thermostat to 0.

[0104] Preferably, if Figure 3 As shown, the target opening of the electronic thermostat is determined according to the target opening control enable of the electronic thermostat, the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, and the coolant temperature at the radiator outlet, and further includes:

[0105] Step S31: when the target opening control enable of the electronic thermostat is set to 0, the target opening of the electronic thermostat is controlled to be zero;

[0106] Step S32: when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic;

[0107] Step S33: When the target opening control enable of the electronic thermostat is set to 2, the target opening of the electronic thermostat is controlled to be frozen and maintain the value at the last moment.

[0108] Preferably, if Figure 4 As shown, when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to the preset logic, wherein the calculation process of the target opening of the electronic thermostat is divided into four stages, namely, the first stage step S321, the second stage step S322, the third stage step S323 and the fourth stage step S324, specifically including:

[0109] Step S321: when the coolant temperature at the outlet of the stack rises to the second temperature limit value, the target opening of the electronic thermostat is calculated to be the first opening (the first opening is generally relatively small, such as 2% to 3%) according to the preset logic, and the electronic thermostat is controlled to execute the first opening, so as to slowly mix the coolants in the large and small cycles while ensuring that the coolant temperature at the inlet of the stack is stable; wherein, during the process of the electronic thermostat executing the first opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the third temperature limit value, the third temperature limit value is set to 62°C, and the first stage of control completion mark position of the electronic thermostat is set to 1;

[0110] Step S322: When the control completion mark position of the first stage of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be the second opening according to the preset logic, and the electronic thermostat is controlled to execute the second opening (the second opening is generally relatively large, such as 12%), and the coolant in the large and small cycles is quickly mixed for the first time; wherein, during the process of the electronic thermostat executing the second opening, the coolant temperature at the inlet of the battery stack continues to rise, and the rate of change of the coolant temperature at the inlet of the battery stack continues to decrease;

[0111] When the rate of change of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be a third opening according to the preset logic (the third opening is generally relatively small, such as 2% to 3%), and the electronic thermostat is controlled to execute the third opening, so that the coolant temperature in the large cycle can be quickly increased while ensuring that the coolant temperature at the inlet of the stack does not fluctuate greatly; wherein, during the process of the electronic thermostat executing the third opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the fourth temperature limit value (such as 66°C), the second stage of the control completion mark position of the electronic thermostat is set to 1;

[0112] Step S323: When the second stage control completion mark position of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be a fourth opening (such as 30%) according to the preset logic, and the electronic thermostat is controlled to execute the fourth opening, and the coolant in the large and small cycles is quickly mixed for the second time; wherein, during the process of the electronic thermostat executing the fourth opening, the temperature of the coolant in the fuel cell stack inlet continues to rise, and the rate of change of the temperature of the coolant in the fuel cell stack inlet continues to decrease;

[0113] When the change rate of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be the fifth opening according to the preset logic (the fifth opening is generally relatively small, such as 2% to 3%), and the electronic thermostat is controlled to execute the fifth opening, so as to quickly increase the coolant temperature in the large cycle while ensuring that the coolant temperature at the inlet of the stack does not fluctuate greatly; wherein, during the process of the electronic thermostat executing the fifth opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the fifth temperature limit value (such as 70°C), the third stage of the control completion mark position of the electronic thermostat is set to 1;

[0114] Step S324: when the third stage control completion mark position of the electronic thermostat is 1, determine whether the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value (such as 75° C.);

[0115] If the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value, determine whether the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet is less than or equal to a temperature difference threshold value (e.g., 8°C); if the difference is less than or equal to the temperature difference threshold value, control the electronic thermostat to perform a maximum opening; if the difference is greater than the temperature difference threshold value, calculate the target opening of the electronic thermostat as a sixth opening according to a preset logic, and control the electronic thermostat to perform the sixth opening;

[0116] If the coolant temperature at the stack outlet is greater than the sixth temperature limit value, the electronic thermostat is controlled to perform a maximum opening (eg, 100%).

[0117] Specifically, when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic, and further includes:

[0118] When the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat in each stage is calculated using the preset formula (1), and the preset formula (1) is:

[0119]

[0120] in, Refers to the target opening of the electronic thermostat. Refers to the coolant flow in the small cycle, Refers to the coolant flow rate in the large cycle, + , Refers to the total coolant flow entering the stack through the electronic thermostat; Refers to the coolant temperature at the stack outlet. Refers to the coolant temperature at the radiator outlet. Refers to the target temperature of the coolant at the stack inlet.

[0121] Preferably, if Figure 5 As shown, the first stage step S321 also includes:

[0122] Step S3211: Detect the coolant temperature at the stack outlet is greater than or equal to the second temperature limit value;

[0123] Step S3212: Setting the target temperature of the coolant at the stack inlet ,in, is the first expected temperature, the first expected temperature Take 2℃ as a fixed value; according to the target temperature of the coolant at the inlet of the stack , using formula (1) to calculate the target opening of the electronic thermostat as a first opening;

[0124] Step S3213: controlling the electronic thermostat to execute the first opening, and feeding back the current actual opening of the electronic thermostat;

[0125] Step S3214: Determine the coolant temperature at the stack outlet Is it greater than or equal to the third temperature limit value? If so, execute step S3215; if not, return to step S3213;

[0126] Step S3215: Set the first stage control completion flag position of the electronic thermostat to 1.

[0127] Preferably, if Figure 6 As shown, the second stage step S322 further includes:

[0128] Step S3221: Detecting that the first stage control completion mark position of the electronic thermostat is 1;

[0129] Step S3222: Look up the first preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain the second expected temperature ;

[0130] An embodiment of the first preset curve is as follows:

[0131] ;

[0132] Step S3223: Setting the target temperature of the coolant at the stack inlet , according to the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a second opening;

[0133] Step S3224: controlling the electronic thermostat to execute the second opening, and feeding back the current actual opening of the electronic thermostat;

[0134] Step S3225: acquiring the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3226; if not, returning to step S3224;

[0135] Step S3226: Setting the target temperature of the coolant at the stack inlet ,in, is the third expected temperature, the third expected temperature Take 2℃ as a fixed value; according to the target temperature of the coolant at the inlet of the stack , using formula (1) to calculate the target opening of the electronic thermostat as a third opening;

[0136] Step S3227: controlling the electronic thermostat to execute the third opening, and feeding back the current actual opening of the electronic thermostat;

[0137] Step S3228: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fourth temperature limit value? If so, execute step S3229; if not, return to step S3227;

[0138] Step S3229: Set the second stage control completion flag position of the electronic thermostat to 1.

[0139] Preferably, if Figure 7 As shown, the third stage step S323 further includes:

[0140] Step S3231: Detecting that the second stage control completion mark position of the electronic thermostat is 1;

[0141] Step S3232: Look up the second preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain a fourth expected temperature. ;

[0142] An embodiment of the second preset curve is as follows:

[0143] ;

[0144] Step S3233: Setting the target temperature of the coolant at the stack inlet , according to the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a fourth opening;

[0145] Step S3234: controlling the electronic thermostat to execute the fourth opening, and feeding back the current actual opening of the electronic thermostat;

[0146] Step S3235: obtaining the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3236; if not, returning to executing step S3234;

[0147] Step S3236: Setting the target temperature of the coolant at the stack inlet ,in, is the fifth expected temperature, the fifth expected temperature Take 2℃; according to the target temperature of the coolant at the inlet of the stack , using formula (1) to calculate the target opening of the electronic thermostat as the fifth opening;

[0148] Step S3237: controlling the electronic thermostat to execute the fifth opening, and feeding back the current actual opening of the electronic thermostat;

[0149] Step S3238: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fifth temperature limit value? If so, execute step S3239; if not, return to execute step S3237;

[0150] Step S3239: Set the third stage control completion flag position of the electronic thermostat to 1.

[0151] Preferably, if Figure 8 As shown, the fourth stage step S324 further includes:

[0152] Step S3241: Detecting that the third stage control completion mark position of the electronic thermostat is 1;

[0153] Step S3242: Determine the coolant temperature at the stack outlet Is it less than or equal to the sixth temperature limit value? If so, execute step S3243; if not, execute step S3246;

[0154] Step S3243: Calculate the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet, and determine whether it is less than or equal to the temperature difference threshold, for example, the temperature difference threshold is 8°C; if so, execute step S3246; if not, execute step S3244;

[0155] Step S3244: Setting the target temperature of the coolant at the stack inlet ,in, is the sixth expected temperature, the sixth expected temperature Take 4℃; according to the target temperature of the coolant at the inlet of the stack , using formula (1) to calculate the target opening of the electronic thermostat as the sixth opening;

[0156] Step S3245: controlling the electronic thermostat to execute the sixth opening, and feeding back the current actual opening of the electronic thermostat;

[0157] Step S3246: Control the electronic thermostat to perform the maximum opening.

[0158] The control method of the electronic thermostat provided in the embodiment of the present invention can reduce the temperature fluctuation of the coolant at the inlet of the battery stack during the opening process of the electronic thermostat, and quickly complete the mixing of the large and small circulating coolants.

[0159] As another embodiment of the present invention, a control device for an electronic thermostat is provided, which is used to implement the control method for the electronic thermostat described above. The control device for the electronic thermostat includes:

[0160] An acquisition module is used to obtain in real time the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature, and the stack output power;

[0161] A calculation module, used for calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power;

[0162] A determination module is used to determine the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, and the coolant temperature at the radiator outlet, and control the electronic thermostat to execute the target opening.

[0163] The working principle of the control device of the electronic thermostat provided by the present invention can be referred to the description of the control method of the electronic thermostat in the foregoing text, and will not be repeated here.

[0164] As another embodiment of the present invention, a fuel cell thermal management system is provided. Fig. 9As shown, it includes: a fuel cell stack 1, a first temperature sensor 2, a second temperature sensor 3, an electronic water pump 4, an electronic thermostat 5, a third temperature sensor 6, a radiator 7, a cooling fan 8, a fuel cell control unit 9, a voltage sensor 10, a current sensor 11 and an ambient temperature sensor 12, wherein the fuel cell control unit 9 is connected to the first temperature sensor 2, the second temperature sensor 3, the electronic water pump 4, the electronic thermostat 5, the third temperature sensor 6, the cooling fan 8, the voltage sensor 10, the current sensor 11 and the ambient temperature sensor 12 through a wiring harness, and the fuel cell The fuel cell control unit 9 includes the control device of the electronic thermostat mentioned above. The coolant at the outlet of the fuel cell stack 1 is pumped by the electronic water pump 4, flows through the electronic thermostat 5 and is transported back to the inlet of the fuel cell stack 1, which is called a small cycle. The coolant in the small cycle is a high-temperature coolant; the other cycle passes through the radiator 7 and the cooling fan 8 and then flows through the electronic thermostat 5 to the inlet of the fuel cell stack 1 after heat dissipation, which is called a large cycle. The coolant in the large cycle is a low-temperature coolant; the fuel cell control unit 9 controls the opening of the electronic thermostat 5 to allocate the ratio of high-temperature coolant and low-temperature coolant entering the fuel cell stack 1;

[0165] The first temperature sensor 2 is arranged at the outlet of the fuel cell stack 1, and is used to detect the coolant temperature at the fuel cell stack outlet; the second temperature sensor 3 is arranged at the inlet of the fuel cell stack 1, and is used to detect the coolant temperature at the inlet of the fuel cell stack; the third temperature sensor 6 is arranged at the outlet of the radiator 7, and is used to detect the coolant temperature at the radiator outlet; the ambient temperature sensor 12 is used to detect the current ambient temperature; the voltage sensor 10 is used to detect the fuel cell stack output voltage, and the current sensor 11 is used to detect the fuel cell stack output current. The fuel cell control unit 9 can calculate the fuel cell stack output power based on the fuel cell stack output voltage and the fuel cell stack output current.

[0166] It should be noted that before the fuel cell is started, the fuel cell control unit 9 is powered on and initialization is completed. The fuel cell control unit 9 adjusts the electronic thermostat 5 according to the collected sensor signal to control the mixing of the large and small circulating coolants.

[0167] The working principle of the fuel cell thermal management system provided by the embodiment of the present invention can be referred to the description of the control method of the electronic thermostat above, which will not be repeated here.

[0168] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for controlling an electronic thermostat, characterized in that: The control method of the electronic thermostat comprises: Step S1: acquiring in real time the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature and the stack output power; Step S2: Calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power; Step S3: determining the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the stack outlet coolant temperature, the stack inlet coolant temperature, and the radiator outlet coolant temperature, and controlling the electronic thermostat to execute the target opening; Wherein, the target opening of the electronic thermostat is determined according to the target opening control enable of the electronic thermostat, the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, and the coolant temperature at the radiator outlet, and further includes: Step S31: when the target opening control enable of the electronic thermostat is set to 0, the target opening of the electronic thermostat is controlled to be zero; Step S32: when the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic; Step S33: when the target opening control enable of the electronic thermostat is set to 2, the target opening of the electronic thermostat is controlled to be frozen and maintain the value at the last moment; When the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to the preset logic, wherein the calculation process of the target opening of the electronic thermostat is divided into four stages, namely, the first stage step S321, the second stage step S322, the third stage step S323 and the fourth stage step S324, specifically including: Step S321: when the coolant temperature at the outlet of the stack rises to the second temperature limit value, the target opening of the electronic thermostat is calculated to be the first opening according to the preset logic, and the electronic thermostat is controlled to execute the first opening; wherein, during the process of the electronic thermostat executing the first opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the third temperature limit value, the control completion mark position of the first stage of the electronic thermostat is set to 1; Step S322: when the control completion mark position of the first stage of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be a second opening according to the preset logic, and the electronic thermostat is controlled to execute the second opening; wherein, during the process of the electronic thermostat executing the second opening, the temperature of the coolant at the inlet of the stack continues to rise, and the rate of change of the temperature of the coolant at the inlet of the stack continues to decrease; When the rate of change of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be a third opening according to a preset logic, and the electronic thermostat is controlled to execute the third opening; wherein, during the process of the electronic thermostat executing the third opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to a fourth temperature limit value, the second stage control completion mark position of the electronic thermostat is set to 1; Step S323: when the second stage control completion mark position of the electronic thermostat is 1, the target opening of the electronic thermostat is calculated to be a fourth opening according to the preset logic, and the electronic thermostat is controlled to execute the fourth opening; wherein, during the process of the electronic thermostat executing the fourth opening, the temperature of the coolant at the inlet of the stack continues to rise, and the rate of change of the temperature of the coolant at the inlet of the stack continues to decrease; When the rate of change of the coolant temperature at the inlet of the stack decreases to zero, the target opening of the electronic thermostat is calculated to be the fifth opening according to the preset logic, and the electronic thermostat is controlled to execute the fifth opening; wherein, during the process of the electronic thermostat executing the fifth opening, the coolant temperature at the outlet of the stack continues to rise, and when the coolant temperature at the outlet of the stack rises to the fifth temperature limit value, the control completion mark position of the third stage of the electronic thermostat is set to 1; Step S324: when the third stage control completion mark position of the electronic thermostat is 1, determining whether the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value; If the coolant temperature at the stack outlet is less than or equal to the sixth temperature limit value, determine whether the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet is less than or equal to the temperature difference threshold value; if the difference is less than or equal to the temperature difference threshold value, control the electronic thermostat to perform the maximum opening; if the difference is greater than the temperature difference threshold value, calculate the target opening of the electronic thermostat as the sixth opening according to the preset logic, and control the electronic thermostat to perform the sixth opening; If the coolant temperature at the stack outlet is greater than the sixth temperature limit value, the electronic thermostat is controlled to perform the maximum opening.

2. The control method of the electronic thermostat according to claim 1, characterized in that: The target opening control enabling of the electronic thermostat is calculated according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power, and further includes: Step S21: start; Step S22: determine whether the current stack outlet coolant temperature is greater than or equal to the second temperature limit value; if so, execute step S23; if not, execute step S25; Step S23: querying the minimum output power curve of the battery stack according to the current ambient temperature to obtain the lower limit value of the battery stack output power when the electronic thermostat is turned on; Step S24: determine whether the current stack output power is greater than or equal to the stack output power lower limit value when the electronic thermostat is turned on; if so, execute step S26; if not, execute step S25; Step S25: Determine whether the current stack outlet coolant temperature is less than or equal to the first temperature limit value; if so, execute step S28; if not, execute step S27; Step S26: setting the target opening control enable of the electronic thermostat to 1; Step S27: setting the target opening control enable of the electronic thermostat to 2; Step S28: setting the target opening control enable of the electronic thermostat to 0.

3. The control method of the electronic thermostat according to claim 1, characterized in that: When the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat is calculated according to a preset logic, and further includes: When the target opening control enable of the electronic thermostat is set to 1, the target opening of the electronic thermostat in each stage is calculated using the preset formula (1), and the preset formula (1) is: ； in, Refers to the target opening of the electronic thermostat. Refers to the coolant flow in the small cycle, Refers to the coolant flow rate in the large cycle, + , Refers to the total coolant flow entering the stack through the electronic thermostat; Refers to the coolant temperature at the stack outlet. Refers to the coolant temperature at the radiator outlet. Refers to the target temperature of the coolant at the stack inlet.

4. The control method of the electronic thermostat according to claim 3, characterized in that: The first stage step S321 further includes: Step S3211: Detecting the coolant temperature at the stack outlet is greater than or equal to the second temperature limit value; Step S3212: Setting the target temperature of the coolant at the stack inlet ,in, is the first expected temperature, and the target opening of the electronic thermostat is calculated by formula (1) as the first opening; Step S3213: controlling the electronic thermostat to execute the first opening, and feeding back the current actual opening of the electronic thermostat; Step S3214: Determine the coolant temperature at the stack outlet Is it greater than or equal to the third temperature limit value? If so, execute step S3215; if not, return to step S3213; Step S3215: Set the first stage control completion flag position of the electronic thermostat to 1.

5. The control method of the electronic thermostat according to claim 3, characterized in that: The second stage step S322 further includes: Step S3221: Detecting that the first stage control completion mark position of the electronic thermostat is 1; Step S3222: Look up the first preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain the second expected temperature ; Step S3223: Setting the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a second opening; Step S3224: controlling the electronic thermostat to execute the second opening, and feeding back the current actual opening of the electronic thermostat; Step S3225: acquiring the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3226; if not, returning to step S3224; Step S3226: Setting the target temperature of the coolant at the stack inlet ,in, is the third expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the third opening; Step S3227: controlling the electronic thermostat to execute the third opening, and feeding back the current actual opening of the electronic thermostat; Step S3228: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fourth temperature limit value? If so, execute step S3229; if not, return to step S3227; Step S3229: Set the second stage control completion flag position of the electronic thermostat to 1.

6. The control method of the electronic thermostat according to claim 3, characterized in that: The third stage step S323 further includes: Step S3231: Detecting that the second stage control completion mark position of the electronic thermostat is 1; Step S3232: Look up the second preset curve according to the difference between the current radiator outlet coolant temperature and the stack outlet coolant temperature to obtain a fourth expected temperature. ; Step S3233: Setting the target temperature of the coolant at the stack inlet , using formula (1) to calculate the target opening of the electronic thermostat as a fourth opening; Step S3234: controlling the electronic thermostat to execute the fourth opening, and feeding back the current actual opening of the electronic thermostat; Step S3235: obtaining the change rate of the coolant temperature at the inlet of the stack in real time, and determining whether the change rate of the coolant temperature at the inlet of the stack is less than or equal to zero; if so, executing step S3236; if not, returning to executing step S3234; Step S3236: Setting the target temperature of the coolant at the stack inlet ,in, is the fifth expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the fifth opening; Step S3237: controlling the electronic thermostat to execute the fifth opening, and feeding back the current actual opening of the electronic thermostat; Step S3238: Determine the coolant temperature at the stack outlet Is it greater than or equal to the fifth temperature limit value? If so, execute step S3239; if not, return to execute step S3237; Step S3239: Set the third stage control completion flag position of the electronic thermostat to 1.

7. The control method of the electronic thermostat according to claim 3, characterized in that: The fourth stage step S324 further includes: Step S3241: Detecting that the third stage control completion mark position of the electronic thermostat is 1; Step S3242: Determine the coolant temperature at the stack outlet Is it less than or equal to the sixth temperature limit value? If so, execute step S3243; if not, execute step S3246; Step S3243: Calculate the difference between the coolant temperature at the stack outlet and the coolant temperature at the radiator outlet, and determine whether it is less than or equal to the temperature difference threshold; if so, execute step S3246; if not, execute step S3244; Step S3244: Setting the target temperature of the coolant at the stack inlet ,in, is the sixth expected temperature; the target opening of the electronic thermostat is calculated by formula (1) to be the sixth opening; Step S3245: controlling the electronic thermostat to execute the sixth opening, and feeding back the current actual opening of the electronic thermostat; Step S3246: Control the electronic thermostat to perform the maximum opening.

8. A control device for an electronic thermostat, used to implement the control method for an electronic thermostat according to any one of claims 1 to 7, characterized in that: The control device of the electronic thermostat comprises: An acquisition module is used to obtain the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, the coolant temperature at the radiator outlet, the ambient temperature and the stack output power in real time; A calculation module, used for calculating the target opening control enable of the electronic thermostat according to the coolant temperature at the stack outlet, the ambient temperature and the stack output power; A determination module is used to determine the target opening of the electronic thermostat according to the target opening control enable of the electronic thermostat, the coolant temperature at the stack outlet, the coolant temperature at the stack inlet, and the coolant temperature at the radiator outlet, and control the electronic thermostat to execute the target opening.

9. A fuel cell thermal management system, characterized in that: include: A fuel cell stack (1), a first temperature sensor (2), a second temperature sensor (3), an electronic water pump (4), an electronic thermostat (5), a third temperature sensor (6), a radiator (7), a cooling fan (8), a fuel cell control unit (9), a voltage sensor (10), a current sensor (11), and an ambient temperature sensor (12); the fuel cell control unit (9) is connected to the first temperature sensor (2), the second temperature sensor (3), the electronic water pump (4), the electronic thermostat (5), the third temperature sensor (6), the cooling fan (8), the voltage sensor (10), the current sensor (11), and the ambient temperature sensor (12) through a wiring harness. The fuel cell control unit (9) includes the control device of the electronic thermostat according to claim 8, the coolant at the outlet of the stack (1) is pumped by the electronic water pump (4), one path flows through the electronic thermostat (5) and is transported back to the inlet of the stack (1), which is called a small cycle, and the coolant in the small cycle is a high-temperature coolant; the other path flows through the electronic thermostat (5) after heat dissipation through the radiator (7) and the cooling fan (8) and is transported to the inlet of the stack (1), which is called a large cycle, and the coolant in the large cycle is a low-temperature coolant; the fuel cell control unit (9) controls the opening of the electronic thermostat (5) to allocate the ratio of high-temperature coolant to low-temperature coolant entering the stack (1); The first temperature sensor (2) is arranged at the outlet of the fuel cell stack (1) and is used to detect the coolant temperature at the fuel cell stack outlet; the second temperature sensor (3) is arranged at the inlet of the fuel cell stack (1) and is used to detect the coolant temperature at the fuel cell stack inlet; the third temperature sensor (6) is arranged at the outlet of the radiator (7) and is used to detect the coolant temperature at the radiator outlet; the ambient temperature sensor (12) is used to detect the current ambient temperature; the voltage sensor (10) is used to detect the fuel cell stack output voltage, the current sensor (11) is used to detect the fuel cell stack output current, and the fuel cell control unit (9) can calculate the fuel cell stack output power based on the fuel cell stack output voltage and the fuel cell stack output current.

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