Fuel cell energy recovery system and engineering machinery

Abstract

The utility model relates to the technical field of fuel cells, and discloses a fuel cell energy recovery system and engineering machinery, the fuel cell energy recovery system comprises: an electric pile module provided with a cooling liquid outlet and a cooling liquid return port; the liquid outlet path is communicated with the cooling liquid outlet and is provided with a radiator; the liquid return path is communicated between the cooling liquid return opening and the liquid outlet path, the liquid return path comprises a flow adjusting device, a first liquid return branch and a second liquid return branch, the first liquid return branch and the second liquid return branch are arranged in parallel, a phase change energy storage module is arranged on the second liquid return branch, and the flow adjusting device can adjust the flow of the second liquid return branch. The flow adjusting device comprises a flow adjusting pump arranged on the second liquid return branch. According to the fuel cell energy recovery system and the engineering machinery, the efficiency of the fuel cell system can be improved.

Description

Technical Field

[0001] The present application belongs to the field of fuel cell technology, and specifically relates to a fuel cell energy recovery system and engineering machinery. Background Art

[0002] A fuel cell is a device that converts chemical energy into electrical energy. A large portion of the energy in a fuel cell system exists in the form of heat. At present, the efficiency of fuel cell systems is not high. The existing technology uses an expander to achieve fuel cell exhaust energy recovery, but the recovery ratio is relatively small. Summary of the invention

[0003] The purpose of this application is to provide a fuel cell energy recovery system and engineering machinery that can improve the efficiency of the fuel cell system.

[0004] In order to achieve the above-mentioned object, the present application provides a fuel cell energy recovery system on one hand, the fuel cell energy recovery system comprising:

[0005] The stack module is provided with a cooling liquid outlet and a cooling liquid return port;

[0006] a liquid outlet passage, connected to the cooling liquid outlet and provided with a radiator; and

[0007] The liquid return liquid circuit is connected between the cooling liquid return port and the liquid outlet liquid circuit. The liquid return liquid circuit includes a flow regulating device and a first liquid return branch and a second liquid return branch arranged in parallel. The second liquid return branch is provided with a phase change energy storage module. The flow regulating device can regulate the flow of the second liquid return branch.

[0008] In some specific embodiments, the flow regulating device includes a flow regulating pump disposed on the second liquid return branch.

[0009] In some specific embodiments, the fuel cell energy recovery system further includes a heat utilizing unit, and the heat utilizing unit is connected to the phase change energy storage module for heat exchange.

[0010] In some specific embodiments, the liquid outlet path further comprises:

[0011] A main liquid outlet path, connected to the cooling liquid outlet and provided with a thermostat;

[0012] A first liquid outlet branch is connected between the first liquid outlet of the thermostat and the liquid return path, and the radiator is arranged on the first liquid outlet branch; and

[0013] The second liquid outlet branch is connected between the second liquid outlet of the thermostat and the liquid return path to be arranged in parallel with the first liquid outlet branch.

[0014] In some specific embodiments, a first sensor is provided on the main liquid outlet line, and the first sensor is used to detect the outlet temperature of the coolant flowing out of the cooling outlet. The fuel cell energy recovery system also includes a control device which is communicatively connected to the flow regulating device and the first sensor respectively, and the control device is used to control the operation of the flow regulating device according to the outlet temperature detected by the first sensor.

[0015] In some specific embodiments, the control device is also connected to the thermostat for communication and is used to control the operation of the thermostat according to the outlet temperature of the liquid detected by the first sensor.

[0016] In some specific embodiments, the radiator is provided with a cooling fan, and the control device is also in communication connection with the cooling fan and is used to control the rotation speed of the cooling fan according to the liquid outlet temperature detected by the first sensor.

[0017] In some specific embodiments, a second sensor communicatively connected to the control device is provided on the first liquid return branch, and the second sensor is used to detect the liquid return temperature of the coolant returning from the first liquid return branch to the cooling liquid return port. The control device is also used to control the start-up of the fuel cell or control the operation of the flow regulating device according to the liquid return temperature detected by the second sensor.

[0018] In some specific implementations, a circulating water pump is also provided on the main liquid outlet path.

[0019] In some specific embodiments, a water replenishment tank is also provided on the main liquid outlet line.

[0020] A second aspect of the present application provides an engineering machine, which includes the above-mentioned fuel cell energy recovery system.

[0021] Through the above technical solution, when the fuel cell undergoes an electrochemical reaction, a large part of the energy exists in the form of heat energy due to the polarization of the battery. This solution uses a phase change energy storage module to recover the heat energy released during the reaction, thereby realizing energy recovery of the fuel cell system and improving the efficiency of the fuel cell system. At the same time, the phase change energy storage module is arranged on the second liquid return branch of the coolant, and the flow rate of the second liquid return branch can be adjusted by the flow regulating device, that is, the heat absorption and heat release function of the phase change energy storage module can be used to assist in adjusting the reaction temperature of the fuel cell system, so as to maintain the reaction temperature of the fuel cell system within an appropriate range and extend the service life of the fuel cell.

[0022] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0024] Figure 1 A schematic structural diagram of a fuel cell energy recovery system according to a specific embodiment of the present application is shown;

[0025] Figure 2 A flow chart of a control method for a fuel cell energy recovery system according to a specific embodiment of the present application is shown.

[0026] Description of Reference Numerals

[0027] 1 Stack module 11 Cooling outlet

[0028] 12 Cooling liquid return port 21 Liquid outlet main line

[0029] 211 Thermostat 212 First sensor

[0030] 213 Circulating water pump 214 Water supply tank

[0031] 215 Deionization device 22 First liquid outlet branch

[0032] 221 Radiator 222 Filter

[0033] 223 Third sensor 23 Second liquid outlet branch

[0034] 24 Three-way valve 31 First liquid return branch

[0035] 311 Second sensor 32 Second liquid return branch

[0036] 321 Phase change energy storage module 33 Flow regulating device

[0037] 4 Heat unit 41 Heat exchanger

[0038] 42 Fourth sensor DETAILED DESCRIPTION

[0039] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0040] Fuel cells can convert the chemical energy of fuel and oxidant into electrical energy. Their energy conversion efficiency is not limited by the theoretical efficiency of the Carnot heat engine cycle. They have the advantages of high efficiency, environmental friendliness, quietness, and high reliability. However, when the electrochemical reaction of the fuel cell occurs, a large part of the energy exists in the form of heat energy due to the polarization of the battery, resulting in low efficiency of the fuel cell system.

[0041] In view of this, if Figure 1 As shown, the first aspect of the present application provides a fuel cell energy recovery system, which includes a stack module 1, a liquid outlet and a liquid return. The stack module 1 is provided with a cooling liquid outlet 11 and a cooling liquid return 12, the liquid outlet is connected to the cooling liquid outlet 11 and is provided with a radiator 221, and the liquid return is connected between the cooling liquid return 12 and the liquid outlet. In this way, a coolant circulation loop can be formed to cool the stack module 1.

[0042] The liquid return path includes a flow regulating device 33 and a first liquid return branch 31 and a second liquid return branch 32 arranged in parallel. A phase change energy storage module 321 is provided on the second liquid return branch 32. The flow regulating device 33 can adjust the flow of the second liquid return branch 32. In this way, by adopting the phase change energy storage module 321, the heat energy released by the stack module 1 during the reaction process can be recovered to achieve energy recovery of the fuel cell system. At the same time, the heat absorption and heat release function of the phase change energy storage module 321 can assist in adjusting the reaction temperature of the fuel cell system to maintain the reaction temperature of the fuel cell system within an appropriate range.

[0043] Among them, the return liquid circuit includes a flow regulating device 33, which can regulate the flow of the second return liquid branch 32. In this way, when the battery stack module 1 releases a large amount of heat, the flow regulating device 33 can increase the flow of the second return liquid branch 32, so that the phase change energy storage module 321 on the second return liquid branch 32 can absorb heat and store energy; and when receiving the fuel cell start-up instruction, if the temperature of the battery stack module 1 is too low, the flow regulating device 33 can be controlled to increase the flow of the second return liquid branch 32, so that the phase change energy storage module 321 on the second return liquid branch 32 can increase heat release to increase the temperature of the battery stack module 1, thereby assisting in regulating the reaction temperature of the fuel cell system, maintaining the reaction temperature of the fuel cell system within an appropriate range, and reducing the lag effect of the radiator temperature.

[0044] In addition, the phase change energy storage module 321 may include phase change materials, heat transfer media, heat transfer tubes, etc., which can be used to store the thermal energy generated by the fuel cell system. The thermal energy can be used for hydrogen heating, fuel cell system heating and other heat-using units. It can also play a role in thermal energy buffering to prevent the fuel cell stack from overheating, fine-tune the operating temperature of the fuel cell system, and extend the service life.

[0045] In some specific embodiments, Figure 1As shown, the flow regulating device 33 may include a flow regulating pump, which is arranged on the second liquid return branch 32, that is, the flow regulating pump and the phase change energy storage module 321 are arranged in series on the second liquid return branch 32. In this way, by increasing the flow of the flow regulating pump, the flow of the second liquid return branch 32 can be increased. Similarly, by reducing the flow of the flow regulating pump, the flow of the second liquid return branch 32 can be reduced, thereby adjusting the flow of the second liquid return branch 32. In addition, by arranging the flow regulating pump on the second liquid return branch 32, the circulation pressure of the coolant circulation loop can be appropriately increased, which is beneficial to the circulation and transportation of the coolant, making the overall operation more reliable.

[0046] Alternatively, in some other specific embodiments, the liquid return path has a diversion port for diverting the coolant to the first liquid return branch 31 and the second liquid return branch 32, and the flow regulating device 33 may also include a three-way flow regulating device disposed on the diversion port, such as a diversion valve or a thermostat. In this way, the flow regulating function of the second liquid return branch 32 can also be achieved.

[0047] Optionally, the fuel cell energy recovery system may further include a heat unit 4, which is heat-exchange connected to the phase change energy storage module 321. The heat unit 4 includes, for example, air conditioning heating, power battery preheating, etc. Through the heat exchange connection, the phase change energy storage module 321 can exchange heat with the heat unit 4 to provide heat for the heat unit 4. The phase change energy storage module is heat-exchange connected to the heat unit, which can not only improve the energy recovery efficiency of the fuel cell system while adjusting the reaction temperature of the fuel cell system, but also realize flexible heating of the heat unit through flow regulation.

[0048] In some specific embodiments, the liquid outlet path includes a main liquid outlet path 21, a first liquid outlet branch path 22, and a second liquid outlet branch path 23. The main liquid outlet path 21 is connected to the cooling liquid outlet 11 and is provided with a thermostat 211, the first liquid outlet branch path 22 is connected between the first liquid outlet of the thermostat 211 and the liquid return path, the radiator 221 is provided on the first liquid outlet branch path 22, and the second liquid outlet branch path 23 is connected between the second liquid outlet of the thermostat 211 and the liquid return path to be arranged in parallel with the first liquid outlet branch path 22.

[0049] Specifically, Figure 1As shown, one end of the main liquid outlet 21 is connected to the cooling liquid outlet 11, and the other end of the main liquid outlet 21 is provided with a diversion port, and the thermostat 211 is arranged on the diversion port. The thermostat 211 has a liquid inlet, a first liquid outlet and a second liquid outlet. The liquid inlet of the thermostat 211 is connected to the main liquid outlet 21, the first liquid outlet branch 22 and the second liquid outlet branch 23 are arranged in parallel, the first liquid outlet of the thermostat 211 is connected to the first liquid outlet branch 22, and the second liquid outlet of the thermostat 211 is connected to the second liquid outlet branch 23, so as to realize the diversion and flow rate regulation functions. In this way, when the temperature of the coolant is too low, the thermostat 211 can be controlled to reduce the flow of the first liquid outlet branch 22, so as to avoid or reduce the heat loss of the coolant at the radiator 221. When the coolant temperature is too high, the thermostat 211 can be controlled to increase the flow of the first liquid outlet branch 22, thereby increasing the heat dissipated by the coolant at the radiator 221, thereby increasing the large cycle ratio of the cooling system and reducing the operating temperature of the fuel cell.

[0050] Optionally, the coolant circulation loop of the fuel cell energy recovery system further includes a circulating water pump 213 and a water replenishment tank 214. Figure 1 As shown, the circulating water pump 213 and the water replenishment water tank 214 are respectively arranged on the main liquid outlet path. In addition, a deionization device 215 is also arranged on the liquid outlet channel of the water replenishment water tank 214.

[0051] Alternatively, if Figure 1 As shown, a filter 222 is further provided on the first liquid outlet branch 22 , and the filter 222 is located between the first liquid outlet of the thermostat 211 and the liquid inlet of the radiator 221 .

[0052] Alternatively, if Figure 1 As shown, a first sensor 212 is provided on the main liquid outlet path, and the first sensor 212 is used to detect the outlet temperature of the coolant flowing out of the cooling outlet 11. The fuel cell energy recovery system also includes a control device that is respectively connected to the flow regulating device 33 and the first sensor 212 in communication, and the control device is used to control the flow regulating device 33 to operate according to the outlet temperature detected by the first sensor 212. The outlet temperature detected by the first sensor 212 can roughly reflect the temperature of the battery stack module 1. If the outlet temperature detected by the first sensor 212 is high, it can reflect that the temperature of the battery stack module 1 is relatively high; if the outlet temperature detected by the first sensor 212 is low, it can reflect that the temperature of the battery stack module 1 is relatively low.

[0053] The control device controls the flow regulating device 33 to operate according to the outlet temperature of the coolant flowing out of the cooling outlet 11 detected by the first sensor 212, so as to automatically assist in regulating the reaction temperature of the fuel cell system, maintain the reaction temperature of the fuel cell system within an appropriate range, and reduce the lag effect of the radiator temperature.

[0054] Specifically, Figure 2 As shown, the flow regulating device 33 is controlled to operate according to the outlet temperature of the coolant flowing out of the cooling outlet 11, including:

[0055] Determine that the liquid outlet temperature is greater than or equal to a first preset temperature and less than a second preset temperature, and the first preset temperature is less than the second preset temperature;

[0056] The total required power of the heat consumption unit 4 is obtained and the flow regulating device 33 is controlled to adjust the flow of the second liquid return branch 32 .

[0057] Among them, the first preset temperature is a temperature slightly lower than the normal operating temperature of the fuel cell, and the second preset temperature is a temperature slightly higher than the normal operating temperature of the fuel cell, that is, the first preset temperature is a negative offset of the normal operating temperature of the fuel cell, and the second preset temperature is a positive offset of the normal operating temperature of the fuel cell. The setting value range of the negative offset and the positive offset can be, for example, 1°C to 4°C, or preferably 2°C to 3°C. When the outlet temperature of the coolant flowing out of the cooling liquid outlet 11 exceeds the first preset temperature and is lower than the second preset temperature, it is necessary to release heat from the stack module 1. At this time, the total heat demand power of the heat unit 4 can be obtained, and the flow rate of the second liquid return branch 32 is adjusted according to the total heat demand power of the heat unit 4 and the outlet temperature control flow regulating device 33, so that the heat energy generated by the fuel cell system is stored in the phase change energy storage module 321 and used to heat the heat unit 4, so as to realize energy recovery of the fuel cell system. After obtaining the total heat demand power of the heat unit 4, the flow of the second liquid return branch 32 can be adaptively adjusted according to the preset relationship between the total heat demand power of the heat unit 4 and the flow of the second liquid return branch 32, thereby providing a controllable heating function for the heat unit 4.

[0058] In addition, when the outlet temperature of the coolant flowing out of the cooling outlet 11 exceeds the first preset temperature and is lower than the second preset temperature, the energy storage function of the phase change energy storage module 321 can meet the heat dissipation requirements of the fuel cell stack module 1. By storing heat in the phase change energy storage module 321, the temperature fluctuation of the fuel cell system can be maintained within an appropriate range, and the power consumption of the fuel cell cooling fan can be reduced, thereby improving the efficiency of the fuel cell system.

[0059] Optionally, the control device is also connected to the thermostat 211 for communication and is used to control the action of the thermostat 211 according to the outlet temperature of the liquid detected by the first sensor 212. Specifically, the control device is further configured as follows:

[0060] Determine that the liquid outlet temperature is greater than or equal to the second preset temperature and less than the third preset temperature, and the second preset temperature is less than the third preset temperature;

[0061] The thermostat 211 is controlled to increase the flow rate of the first liquid outlet branch 22 .

[0062] Among them, the third preset temperature is the temperature at which heat dissipation needs to be enhanced. When the outlet temperature of the coolant flowing out of the cooling outlet 11 exceeds the second preset temperature and is lower than the third preset temperature, the energy storage function of the phase change energy storage module 321 cannot fully meet the heat dissipation requirements of the stack module 1. At this time, it is necessary to control the thermostat 211 to increase the flow of the first outlet branch 22, so that the radiator 221 is required to dissipate heat from the coolant. That is, by controlling the thermostat 211 to increase the flow of the first outlet branch 22, the proportion of the large cycle of the heat dissipation system is increased, and the operating temperature of the fuel cell is reduced.

[0063] Optionally, the radiator 221 is provided with a cooling fan for heat dissipation, and the control device is also connected to the cooling fan for communication and is used to control the speed of the cooling fan according to the liquid outlet temperature detected by the first sensor 212. Specifically, the control device is further configured as follows:

[0064] Determining that the liquid outlet temperature is greater than or equal to a third preset temperature;

[0065] Adjust the speed of the cooling fan.

[0066] When the outlet temperature of the coolant flowing out of the cooling liquid outlet 11 exceeds the third preset temperature, the radiator 221 without starting the cooling fan cannot fully meet the heat dissipation demand of the fuel cell module 1. At this time, it is necessary to adjust the speed of the cooling fan. By controlling the speed of the cooling fan, the heat dissipation rate of the radiator 221 is controlled to maintain the temperature of the fuel cell system within a certain appropriate temperature range. Among them, the speed of the cooling fan can be obtained and adjusted according to the outlet temperature. For example, the corresponding relationship between the outlet temperature and the speed value of the cooling fan is built into the control device. By determining the real-time outlet temperature, the corresponding speed value of the cooling fan is obtained, thereby realizing the adjustment of the speed of the cooling fan.

[0067] Further, after the cooling fan runs for a set time, the control device is further configured to:

[0068] Determining that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is less than the preset difference, and adjusting the speed of the cooling fan to maintain the temperature of the fuel cell system within a suitable preset temperature range;

[0069] Determine that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference, and the temperature difference is greater than 0, and control the flow regulating device 33 to increase the flow of the second liquid return branch 32;

[0070] When it is determined that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference and the temperature difference is less than 0, the flow regulating device 33 is controlled to reduce the flow of the second liquid return branch 32 .

[0071] The preset difference may be the absolute value of the upper and lower allowable floating difference of the third preset temperature. If the absolute value of the temperature difference between the outlet liquid temperature and the third preset temperature is less than the preset difference, that is, the outlet liquid temperature is within the allowable floating range of the third preset temperature, the speed of the cooling fan may be further adjusted according to the outlet liquid temperature so that the temperature of the fuel cell system is maintained within a suitable preset temperature range.

[0072] In addition, the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference, and the temperature difference is greater than 0, that is, the liquid outlet temperature exceeds the allowable floating range of the third preset temperature, and the liquid outlet temperature is greater than the upper allowable floating threshold of the third preset temperature. Adjusting the speed of the cooling fan still cannot meet the heat dissipation requirements of the fuel cell module 1. At this time, it is necessary to control the flow regulating device 33 to increase the flow of the second return liquid branch 32 to adjust the heat storage power of the phase change energy storage module 321, so that the heat energy generated by the fuel cell system is stored in the phase change energy storage module 321 and used to heat the heat unit 4, so that the temperature fluctuation of the fuel cell system is maintained within an appropriate range.

[0073] In addition, the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference, and the temperature difference is less than 0, that is, the liquid outlet temperature exceeds the allowable floating range of the third preset temperature, and the liquid outlet temperature is less than the lower allowable floating threshold of the third preset temperature. The heat dissipation demand of the fuel cell stack module 1 is reduced. At this time, the flow regulating device 33 can be controlled to reduce the flow of the second liquid return branch 32 to adjust the heat release power of the phase change energy storage module 321, thereby appropriately reducing the heating heat supplied to the heat unit 4, so that the temperature fluctuation of the fuel cell system is maintained within an appropriate range.

[0074] Furthermore, if Figure 1 As shown, the first liquid return branch 31 is provided with a second sensor 311 which is in communication with the control device. The second sensor 311 is used to detect the return liquid temperature of the coolant flowing back from the first liquid return branch 31 to the cooling liquid return port 12. The control device is also used to control the start-up of the fuel cell or control the action of the flow regulating device 33 according to the return liquid temperature detected by the second sensor 311. Specifically, the control device is also configured as follows:

[0075] Obtaining a start instruction for the fuel cell;

[0076] Determine that the return liquid temperature of the coolant flowing to the cooling liquid return port 12 is less than a fourth preset temperature, and control the flow regulating device 33 to operate according to the return liquid temperature;

[0077] It is determined that the liquid return temperature is greater than or equal to a fourth preset temperature, and the fuel cell is controlled to start.

[0078] Among them, the fourth preset temperature is less than the first preset temperature, and the fourth preset temperature is the heat release temperature threshold of the phase change energy storage module 321. After receiving the fuel cell startup instruction, the control device controls the start of the circulating water pump 213 and obtains the return liquid temperature at this time. If the return liquid temperature is greater than or equal to the fourth preset temperature, the fuel cell startup program is entered; if the return liquid temperature is less than the fourth preset temperature, the flow regulating device 33 is controlled to act to use the phase change energy storage module 321 to release heat until the return liquid temperature is greater than or equal to the fourth preset temperature. Controlling the flow regulating device 33 to act is to adjust the flow of the first liquid outlet branch 22 to adjust the heat release power of the phase change energy storage module 321. The heat release power of the phase change energy storage module 321 can be obtained and adjusted according to the return liquid temperature. For example, the corresponding relationship between the return liquid temperature and the flow of the first liquid outlet branch 22 is built into the control device. By determining the real-time return liquid temperature, the corresponding flow value of the first liquid outlet branch 22 and the adjustment value of the flow regulating device 33 are obtained, thereby realizing the adjustment of the flow regulating device 33.

[0079] Alternatively, if Figure 1 As shown, the liquid inlet end of the liquid return liquid circuit is a confluence, and a three-way valve 24 is provided on the confluence. The three-way valve has two liquid inlets and one liquid outlet. The liquid outlet of the three-way valve is connected to the liquid inlet end of the liquid return liquid circuit, and the two liquid inlets of the three-way valve are connected to the liquid outlet end of the first liquid outlet branch 22 and the liquid outlet end of the second liquid outlet branch 23 respectively.

[0080] Alternatively, if Figure 1 As shown, a third sensor 223 is further provided on the first liquid outlet branch 22, and the third sensor 223 is used to detect the temperature of the coolant flowing out of the radiator 221. The control device can also be connected to the third sensor 223 for communication and can be configured to adjust the temperature of the cooling fan according to the temperature detected by the third sensor 223, thereby further assisting the fuel cell system in adjusting the reaction temperature.

[0081] Alternatively, if Figure 1 As shown, the fuel cell energy recovery system also includes a heat exchange circuit, and the phase change energy storage module 321 is located on the heat exchange circuit to supply heat or absorb heat to the outside. The heat exchange circuit is also provided with a heat exchanger 41 and a fourth sensor 42. The fourth sensor 42 is used to detect the temperature of the heat exchange liquid in the heat exchange circuit.

[0082] Optionally, the first sensor 212, the second sensor 311, the third sensor 223 and the fourth sensor 42 can be temperature pressure sensors in addition to temperature sensors, which can detect the temperature and the pressure of the liquid circuit at the same time, making the fuel cell energy recovery system work more reliably.

[0083] The second aspect of the present application also provides a construction machinery, which includes the above-mentioned fuel cell energy recovery system. Since the construction machinery includes the above-mentioned fuel cell energy recovery system, it also has all the technical effects brought by the fuel cell energy recovery system, so it will not be repeated. Among them, the construction machinery can be a crane, such as a truck crane, a crawler crane or a boom tower crane, etc., or it can be other working machinery such as a pump truck, an aerial work vehicle, a fire truck, a boom-type working robot, etc.

[0084] It should be noted that the structural principles of the components such as the stack module, phase change energy storage module, thermostat, radiator, heat exchanger, water pump and sensor of the present application are well known to technical personnel in this field and do not belong to the core improvement part of the present application, so they will not be repeated here.

[0085] The coolant in the present application may be water or a coolant solution, etc. The outlet temperature of the coolant flowing out of the cooling liquid outlet 11 can be detected and obtained by the first sensor 212 arranged on the main liquid outlet path, and the first sensor 212 is arranged between the cooling liquid outlet 11 and the liquid inlet of the circulating water pump 213; or, the outlet temperature can also be detected and obtained by the temperature sensor arranged on the cooling liquid outlet 11. The return liquid temperature of the coolant flowing to the cooling liquid return port 12 can be detected and obtained by the second sensor 311, and the second sensor 311 is arranged on the first liquid return branch 31; or, the return liquid temperature can also be detected by the liquid path arranged in the liquid return path in the upstream liquid path of the phase change energy storage module 321.

[0086] like Figure 2 As shown, the third aspect of the present application further provides a control method for the above-mentioned fuel cell energy recovery system, the control method comprising:

[0087] The flow rate regulating device 33 is controlled to operate according to the outlet temperature of the coolant flowing out of the coolant outlet 11 .

[0088] In this way, the reaction temperature of the fuel cell system can be automatically assisted to be adjusted, the reaction temperature of the fuel cell system can be maintained within an appropriate range, and the hysteresis effect of the radiator temperature can be reduced.

[0089] Specifically, the flow regulating device 33 is controlled to operate according to the outlet temperature of the coolant flowing out of the cooling outlet 11, including:

[0090] Determine that the liquid outlet temperature is greater than or equal to a first preset temperature and less than a second preset temperature, and the first preset temperature is less than the second preset temperature;

[0091] The total required power of the heat consumption unit 4 is obtained and the flow regulating device 33 is controlled to adjust the flow of the second liquid return branch 32 .

[0092] Furthermore, the control method further includes:

[0093] Determine that the liquid outlet temperature is greater than or equal to the second preset temperature and less than the third preset temperature, and the second preset temperature is less than the third preset temperature;

[0094] The thermostat 211 is controlled to increase the flow rate of the first liquid outlet branch 22 .

[0095] In this way, when the outlet temperature of the coolant flowing out of the cooling outlet 11 exceeds the second preset temperature and is lower than the third preset temperature, the flow of the first outlet branch 22 can be increased by controlling the thermostat 211, thereby increasing the proportion of the large cycle of the heat dissipation system and reducing the operating temperature of the fuel cell.

[0096] Furthermore, the control method further includes:

[0097] Determining that the liquid outlet temperature is greater than or equal to a third preset temperature;

[0098] Adjust the speed of the cooling fan.

[0099] Thus, when the outlet temperature of the coolant flowing out of the cooling outlet 11 exceeds the third preset temperature, the heat dissipation rate of the radiator 221 is controlled by controlling the speed of the cooling fan, so that the temperature of the fuel cell system can be maintained within a certain appropriate temperature range.

[0100] Optionally, after the cooling fan runs for a set time, the control method further includes:

[0101] Determining that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is less than the preset difference, and adjusting the speed of the cooling fan to maintain the temperature of the fuel cell system within a suitable preset temperature range;

[0102] Determine that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference, and the temperature difference is greater than 0, and control the flow regulating device 33 to increase the flow of the second liquid return branch 32;

[0103] When it is determined that the absolute value of the temperature difference between the liquid outlet temperature and the third preset temperature is greater than or equal to the preset difference and the temperature difference is less than 0, the flow regulating device 33 is controlled to reduce the flow of the second liquid return branch 32 .

[0104] In this way, the temperature of the fuel cell system can be maintained within an appropriate preset temperature range.

[0105] Optionally, the control method further includes:

[0106] Obtaining a start instruction for the fuel cell;

[0107] Determine that the return liquid temperature of the coolant flowing to the cooling liquid return port 12 is less than a fourth preset temperature, and control the flow regulating device 33 to operate according to the return liquid temperature;

[0108] Determine that the liquid return temperature is greater than or equal to a fourth preset temperature, and control the fuel cell to start.

[0109] Thus, when the return liquid temperature is lower than the fourth preset temperature, the flow regulating device 33 is controlled to release heat using the phase change energy storage module 321 to assist in regulating the reaction temperature of the fuel cell system and maintain the reaction temperature of the fuel cell system within an appropriate range.

[0110] Specifically, the following will be Figure 2 Taking an example, a control method of a fuel cell energy recovery system according to a specific implementation of the present application is described.

[0111] After receiving the fuel cell start-up instruction, the circulating water pump 213 is started to obtain the return liquid temperature of the coolant of the fuel cell stack at this time. If the return liquid temperature is greater than or equal to the fourth preset temperature, the fuel cell start-up program is entered. If the return liquid temperature is less than the fourth preset temperature, the phase change energy storage module 321 is used to release heat (the heat release power corresponding to the return liquid temperature is obtained by looking up the table) until the return liquid temperature is greater than or equal to the fourth preset temperature;

[0112] During operation, the phase change energy storage module 321 supplies heat to the hydrogen heat exchanger of the fuel cell system. When the outlet temperature of the coolant of the stack is less than the first preset temperature, the operation state is maintained; when the outlet temperature is greater than or equal to the first preset temperature, the total heat demand power of the heat unit 4 is obtained, and the heat storage power of the phase change energy storage module 321 is adjusted;

[0113] When the outlet temperature is lower than the second preset temperature, the judgment logic of the previous stage is returned. When the outlet temperature is higher than or equal to the second preset temperature, the thermostat 211 is adjusted to increase the large circulation ratio of the heat dissipation system and reduce the operating temperature of the fuel cell.

[0114] When the outlet temperature is lower than the third preset temperature, the judgment logic of the previous stage is returned; when the outlet temperature is greater than or equal to the third preset temperature, the speed of the cooling fan under this power state is obtained by looking up the table, so that the temperature of the fuel cell system is maintained within a certain appropriate temperature range;

[0115] After the cooling fan runs for a set time, if the absolute value of the difference between the outlet temperature and the third preset temperature is less than the preset difference δT1, the judgment logic of the previous stage is returned. When the absolute value of the difference between the third preset temperature and the third preset temperature is greater than or equal to the preset difference δT1, the deviation is obtained by looking up the table. If it is a positive deviation, the heat storage power of the phase change energy storage module 321 is adjusted according to the deviation to store heat. If it is a negative deviation, the heat release power of the phase change energy storage module 321 is adjusted according to the deviation to heat, so that the operating temperature of the fuel cell system is maintained within an appropriate range.

[0116] If no shutdown command is received, the process returns to the previous stage judgment logic; if a shutdown command is received, the fuel cell system shuts down.

[0117] To summarize, the fuel cell energy recovery system and operating machinery of the present application can store the heat generated by the operation of the fuel cell system by adding a phase change energy storage module, and can use the stored heat for the operation of the fuel cell system, thereby reducing the system auxiliary consumption and cooling fan power consumption, and improving the efficiency of the fuel cell system; at the same time, the phase change energy storage module can assist the fuel cell system in adjusting the reaction temperature, reduce the lag effect of the radiator temperature, maintain the temperature fluctuation of the fuel cell system within an appropriate range, and extend the service life of the fuel cell.

[0118] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0119] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0120] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0121] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A fuel cell energy recovery system, characterized in that: include: The stack module (1) is provided with a cooling liquid outlet (11) and a cooling liquid return port (12); A liquid outlet passage, connected to the cooling liquid outlet (11) and provided with a radiator (221); and A liquid return liquid path is connected between the cooling liquid return port (12) and the liquid outlet liquid path, the liquid return liquid path comprises a flow regulating device (33) and a first liquid return branch (31) and a second liquid return branch (32) arranged in parallel, the second liquid return branch (32) is provided with a phase change energy storage module (321), and the flow regulating device (33) is capable of regulating the flow of the second liquid return branch (32).

2. The fuel cell energy recovery system according to claim 1, characterized in that: The flow regulating device (33) comprises a flow regulating pump arranged on the second liquid return branch (32).

3. The fuel cell energy recovery system according to claim 1, characterized in that: The fuel cell energy recovery system further comprises a heat utilizing unit (4), and the heat utilizing unit (4) is connected to the phase change energy storage module (321) for heat exchange.

4. The fuel cell energy recovery system according to claim 1, characterized in that: The liquid outlet path also includes: A main liquid outlet path (21), which is in communication with the cooling liquid outlet (11) and is provided with a thermostat (211); A first liquid outlet branch (22) is connected between the first liquid outlet of the thermostat (211) and the liquid return path, and the radiator (221) is arranged on the first liquid outlet branch (22); and The second liquid outlet branch (23) is connected between the second liquid outlet of the thermostat (211) and the liquid return path so as to be arranged in parallel with the first liquid outlet branch (22).

5. The fuel cell energy recovery system according to claim 4, characterized in that: A first sensor (212) is provided on the main liquid outlet path, and the first sensor (212) is used to detect the outlet temperature of the coolant flowing out of the cooling liquid outlet (11). The fuel cell energy recovery system also includes a control device that is communicatively connected to the flow regulating device (33) and the first sensor (212) respectively, and the control device is used to control the operation of the flow regulating device (33) according to the outlet temperature detected by the first sensor (212).

6. The fuel cell energy recovery system according to claim 5, characterized in that: The control device is also connected to the thermostat (211) for communication and is used to control the operation of the thermostat (211) according to the outlet liquid temperature detected by the first sensor (212).

7. The fuel cell energy recovery system according to claim 5, characterized in that: The radiator (221) is provided with a cooling fan, and the control device is also in communication connection with the cooling fan and is used to control the rotation speed of the cooling fan according to the liquid outlet temperature detected by the first sensor (212).

8. The fuel cell energy recovery system according to claim 5, characterized in that: The first liquid return branch (31) is provided with a second sensor (311) which is in communication with the control device. The second sensor (311) is used to detect the liquid return temperature of the cooling liquid that flows back from the first liquid return branch (31) to the cooling liquid return port (12). The control device is also used to control the start-up of the fuel cell or control the operation of the flow regulating device (33) according to the liquid return temperature detected by the second sensor (311).

9. The fuel cell energy recovery system according to claim 4, characterized in that: The main liquid outlet path is also provided with a circulating water pump (213); and / or the main liquid outlet path is also provided with a water replenishment tank (214).

10. An engineering machine, characterized in that: Comprising a fuel cell energy recovery system according to any one of claims 1 to 9.

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