CN117117245A - Air intake and exhaust system and fuel cell - Google Patents

Abstract

The invention discloses an air intake and exhaust system and a fuel cell, wherein the air intake and exhaust system comprises: the air inlet module is communicated with an air inlet of a pile of the fuel cell and is used for supplying high-pressure cathode gas to the pile, and the air inlet module comprises an air compressor and a driving motor, and the driving motor drives the air compressor through a first driving shaft; the exhaust module is communicated with an exhaust port of the fuel cell stack and is used for exhausting high-pressure exhaust gas in the stack, the exhaust module comprises an exhaust turbine and an energy recovery device, the exhaust turbine drives the energy recovery device through a second driving shaft, and the first driving shaft and the second driving shaft are arranged at intervals. The air inlet and exhaust system can avoid the limitation of the same physical rotation speed of the air compressor and the exhaust turbine, optimize the performances of the air compressor and the exhaust turbine, increase the comprehensive energy efficiency of the fuel cell and improve the environmental protection.

Description

Air intake and exhaust system and fuel cell

Technical Field

The invention relates to the technical field of fuel cells, in particular to an air inlet and outlet system and a fuel cell.

Background

In a fuel cell system, an air compressor and a turbine are one of the key components. The main function of the air compressor is to provide oxidant gas for the electrochemical reaction of the fuel cell stack, but when the air compressor works, particularly for a fuel cell system with high power generation, the parasitic power consumption of the air compressor is high due to the fact that the air compressor compresses a large amount of air, and the turbine can recover the exhaust energy of the fuel cell through expansion work, so that the purpose of reducing the power consumption of the air compressor is achieved, and the comprehensive efficiency and the power density of the fuel cell system are improved.

In the related art, the integrated air compressor integrates the air compressor and the turbine, the integrated design limits the optimization space of the air compressor and the turbine in performance and energy efficiency, the isentropic efficiency of the air compressor and the turbine is low, the energy consumption of the air compressor is large, the energy recovery effect of the turbine is poor, and the overall energy efficiency, reliability and economy of the fuel cell system are affected.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, an object of the present invention is to provide an air intake and exhaust system, which can avoid the limitation of the same physical rotation speed of the air compressor and the exhaust turbine, optimize the performance of the air compressor and the exhaust turbine, increase the comprehensive energy efficiency of the fuel cell and improve the environmental protection.

The invention also provides a fuel cell with the air inlet and outlet system.

According to an intake and exhaust system of a fuel cell according to an embodiment of the first aspect of the present invention, the intake and exhaust system includes: the air inlet module is communicated with an air inlet of a pile of the fuel cell and is used for supplying high-pressure cathode gas to the pile, and the air inlet module comprises an air compressor and a driving motor, and the driving motor drives the air compressor through a first driving shaft; the exhaust module is communicated with the exhaust port of the electric pile and used for exhausting high-pressure exhaust gas in the electric pile, the exhaust module comprises an exhaust turbine and an energy recovery device, the exhaust turbine drives the energy recovery device through a second driving shaft, and the first driving shaft and the second driving shaft are arranged at intervals.

According to the air inlet and outlet system of the fuel cell, the air compressor and the air outlet turbine are two relatively independent components, so that the limitation of the same physical rotation speed can be avoided, and the performance of the air compressor and the air outlet turbine can be respectively arranged in respective high-efficiency areas. For the air compressor, the optimization designs of increasing the air characteristic map width of the air compressor, enhancing the isentropic efficiency of the altitude compensation capability and the like can be realized, so that the parasitic power consumption of the air compressor can be saved, and for the exhaust turbine, the optimization matching design of the specific speed and the through-flow capability according to the characteristics of low expansion ratio and high flow of the high-pressure waste gas of the electric pile can be realized, so that the exhaust turbine can operate at the optimal speed ratio, the highest isentropic efficiency is obtained, and the recycling capability of the exhaust turbine and the energy recovery device on the high-pressure waste gas energy can be improved, so that the comprehensive energy efficiency of the fuel cell can be increased, and the environmental protection performance can be improved.

According to some embodiments of the invention, the energy recovery device is configured as a generator, which is electrically connected to at least the drive motor.

In some embodiments, the air compressor is configured as a single-stage air compressor or a multi-stage air compressor.

Further, the air compressor is configured as a two-stage air compressor, and a low-pressure side impeller and a high-pressure side impeller are located at both axial ends of the first drive shaft.

According to some embodiments of the invention, the air intake module further comprises: and one end of the bypass branch is connected with the air outlet of the air compressor, and the other end of the bypass branch is connected with the turbine air inlet of the exhaust turbine.

Further, the bypass branch includes: the inlet pipeline is communicated with the air outlet of the air compressor, and the outlet pipeline is connected with the air inlet of the turbine.

According to some embodiments of the invention, a turbine wheel and an adjustable turbine nozzle are provided within a turbine housing of the exhaust turbine and adapted to achieve flow area adjustment of the exhaust turbine by adjusting a nozzle aperture of the adjustable turbine nozzle.

In some embodiments, the air intake and exhaust system of the fuel cell further comprises an intercooler and a humidifier, wherein an intercooler inlet is connected with an air outlet of the air compressor, an intercooler outlet is connected with a dry inlet end of the humidifier, a dry outlet end of the humidifier is connected with the air inlet, a wet inlet end of the humidifier is connected with the air outlet, and a wet outlet end of the humidifier is connected with the turbine air inlet.

Further, the intake and exhaust system of the fuel cell further includes: the heat exchanger, the heat exchanger import with the air compressor machine gas outlet links to each other, the heat exchanger export with the intercooler import links to each other, the heat exchanger still has waste gas inlet port and exhaust gas outlet, the waste gas inlet port with wet exit end links to each other, the exhaust gas outlet with turbine air inlet links to each other, the intercooler forms to water-cooling intercooler and still has cooling medium import and cooling medium export.

According to an embodiment of the second aspect of the present invention, a fuel cell includes: the electric pile, the air inlet and outlet system and the DC/DC system, wherein the air inlet and outlet system is constructed as any one of the air inlet and outlet system in the embodiment, the air inlet module is connected with the air inlet of the electric pile, the air outlet module is connected with the air outlet of the electric pile, and the DC/DC system is electrically connected with the electric pile.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of a fuel cell according to an embodiment of the first aspect of the present invention;

fig. 2 is a schematic view of a fuel cell according to an embodiment of the second aspect of the present invention.

Reference numerals:

a fuel cell 1;

an air compressor 1111, an air compressor air outlet 1111a, a low pressure side impeller 11111, a high pressure side impeller 11112, an interstage line 11113, a driving motor 1112, a motor controller 11121, a first driving shaft 1113, an air intake filter 1114, an air intake pressure sensor 1115, an air intake temperature sensor 1116, an air intake flow sensor 1117, a thrust bearing 1118, a radial bearing 1119;

an exhaust turbine 1121, a turbine inlet 1121a, a turbine wheel 11211, an adjustable turbine nozzle 11212, an adjustable turbine nozzle electric actuator 11213, a turbine bearing 11214, a turbine housing temperature sensor 11215;

an energy recovery device 1122, a generator inverter 11221, a second drive shaft 1123, a bypass branch 1124, a bypass valve 1125, a tail pipe 1126, a tail pipe muffler 1127;

An intercooler 113, a cooling medium inlet 113a, and a cooling medium outlet 113b;

humidifier 114, dry inlet end 114a, dry outlet end 114b, wet inlet end 114c, wet outlet end 114d;

a heat exchanger 115, an exhaust gas inlet 115a, an exhaust gas outlet 115b;

FCU system 116, atmospheric pressure sensor 1161, atmospheric temperature sensor 1162;

a stack in air pressure sensor 117, a stack in air temperature sensor 118;

pile 12, air inlet 12a, air outlet 12b, DC/DC system 13, high voltage battery 14, consumer 1515.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

An intake and exhaust system and a fuel cell 1 according to an embodiment of the present invention are described below with reference to fig. 1 and 2.

As shown in fig. 1 and 2, the intake and exhaust system of the fuel cell 1 according to the embodiment of the first aspect of the present invention includes: an intake module and an exhaust module.

Wherein the air intake module is in communication with the air intake 12a of the stack 12 of the fuel cell 1 and is configured to supply high-pressure cathode gas to the stack 12, the air intake module including an air compressor 1111 and a driving motor 1112, the driving motor 1112 driving the air compressor 1111 through a first driving shaft 1113; the exhaust module is in communication with the exhaust port 12b of the stack 12 and is for exhausting high-pressure exhaust gas in the stack 12, and the exhaust module includes an exhaust turbine 1121 and an energy recovery device 1122, the exhaust turbine 1121 driving the energy recovery device 1122 through a second drive shaft 1123, the first drive shaft 1113 being disposed at a distance from the second drive shaft 1123.

Fig. 1 and 2 are schematic views of a fuel cell according to an embodiment of the first aspect and an embodiment of the second aspect of the present invention, respectively. It should be noted that, in fig. 1 and 2, the thin solid line indicates an air flow connection in the air system (in which the arrow direction is the advancing direction of the air flow), the dashed arrow line indicates transmission of a control or driving signal (in which the one-way arrow direction is the signal receiving end, and the double arrow represents a communication signal), and the thick solid line indicates an electric power connection (in which the thick solid line with a rounded head indicates a high-voltage dc bus connection, and herein, "high voltage" at the electric power connection indicates high voltage). The air intake and exhaust system (namely the cathode gas system of the fuel cell) is contained in the whole system of the fuel cell and is arranged in movable or fixed equipment or devices, and the complete fuel cell also comprises functional units such as an anode gas system, a water heat management system, a control system and the like.

Specifically, the air intake module has an air intake inlet and an air intake outlet, the air intake outlet is communicated with the air intake 12a of the electric pile 12, the air intake inlet can be communicated with the outside or an air supply device, air in the outside or the air supply device can enter the air intake module through the air intake inlet, the air compressor 1111 is arranged between the air intake inlet and the air intake outlet, the driving motor 1112 drives the air compressor 1111 to work through the first driving shaft 1113, fresh air is compressed by the air compressor 1111 and forms high-pressure cathode gas (mainly in the form of but not limited to oxygen in air) required by the electrochemical reaction of the electric pile 12, and the high-pressure cathode gas can flow to the electric pile 12 and be used by the electrochemical reaction of the electric pile 12 after passing through the air intake outlet of the air intake module and the air intake 12a of the electric pile 12 in sequence, so as to realize the conversion of chemical energy in the fuel cell 1 into electric energy; the exhaust module has an exhaust inlet and an exhaust outlet, the exhaust inlet is communicated with the exhaust port 12b of the electric pile 12, the exhaust outlet can be communicated with the outside, the exhaust turbine 1121 is arranged between the exhaust inlet and the exhaust outlet, and high-pressure exhaust gas in the electric pile 12 can flow to the exhaust turbine 1121 to perform expansion work after passing through the exhaust port 12b of the electric pile 12 and the exhaust inlet of the exhaust module in sequence, so as to provide power for driving the second driving shaft 1123 to rotate, and the second driving shaft 1123 rotates to drive the energy recovery device 1122 so as to convert mechanical energy of the second driving shaft 1123 into other forms of energy (such as electric energy) for use.

The first driving shaft 1113 and the second driving shaft 1123 are spaced apart, that is, the first driving shaft 1113 and the second driving shaft 1123 are separately arranged but can be arranged in the same direction, so that the working independence of the air compressor 1111 and the exhaust turbine 1121 can be improved, the limitation of the specific rotation speed, the through-flow capacity, the expansion ratio, the pressure ratio and the like of the air compressor 1111 and the exhaust turbine 1121 due to the same physical rotation speed when the air compressor 1111 and the exhaust turbine 1121 are arranged on the same shaft can be relieved, and the air compressor 1111 and the exhaust turbine 1121 can be respectively optimally designed according to the respective high-efficiency operation requirements.

Note that the air compressor 1111 is a component for compressing air, and the air compressor 1111 may be, but not limited to, a scroll air compressor, a centrifugal air compressor, or a screw air compressor. The exhaust turbine 1121 is a rotary power machine component that converts the energy of a flowing medium into mechanical work, and is not limited to a certain component; the expansion ratio is a ratio of an absolute pressure value (generally, total pressure) of the gas flowing into the exhaust turbine 1121 to an absolute pressure value (generally, static pressure) of the gas flowing out of the exhaust turbine 1121; the above-mentioned pressure ratio refers to the ratio of the absolute pressure value of the exhaust outlet (generally the total pressure) to the absolute pressure value of the intake inlet (generally the total pressure).

According to the air intake and exhaust system of the fuel cell 1 of the embodiment of the present invention, the air compressor 1111 and the exhaust turbine 1121 are two relatively independent components, which can avoid being limited by the same physical rotation speed, and the performance of the two components can be respectively set in respective high-efficiency areas. For the air compressor 1111, the optimization designs of increasing the air characteristic map width of the air compressor 1111, enhancing the altitude compensation capability and the like can be realized, so that the parasitic power consumption of the air compressor 1111 can be saved, and for the exhaust turbine 1121, the optimization matching design of the specific speed and the through-flow capability according to the characteristics of low expansion ratio and large flow of the high-pressure exhaust gas of the electric pile 12 can be realized, so that the exhaust turbine 1121 can operate at the optimal speed ratio, and the highest isentropic efficiency can be obtained, and the recycling capability of the exhaust turbine 1121 and the energy recycling device 1122 on the high-pressure exhaust gas energy can be improved, so that the comprehensive energy efficiency of the fuel cell 1 can be increased, and the environmental protection performance can be improved.

It should be noted that the isentropic efficiency of the exhaust turbine 1121 refers to the capability of the exhaust turbine 1121 to drive the second driving shaft 1123 to rotate and drive the load during the process of flowing the high-pressure exhaust gas through the exhaust turbine 1121, i.e. the capability of converting the kinetic energy and thermal energy of the gas into the rotational mechanical energy of the shaft output.

In addition, in some embodiments of the present invention, an air intake filter 1114, an air intake pressure sensor 1115, an air intake temperature sensor 1116 and an air intake flow sensor 1117 are disposed between an air intake inlet of the air intake module and the air compressor 1111, wherein the air intake filter 1114 is used for performing physical and chemical filtration on air entering from the air intake inlet, for example, removing dust, metal and other impurities or particles in the air, sulfide, nitrogen oxide, carbon monoxide, ammonia, benzene, sodium chloride particles and the like, so as to avoid damage to components in the air intake and exhaust system and the whole fuel cell 1, thereby playing a role of protecting the air intake and exhaust system and the fuel cell 1, and improving reliability and service life of the components in the air intake and exhaust system and the fuel cell 1; the air intake pressure sensor 1115 is configured to measure the pressure of air intake of the air intake module and feed back a corresponding pressure signal, and monitor the usage state of the air intake filter 1114 (by observing whether the pressure exceeds a threshold, it can be determined whether the air intake filter 1114 is clogged); the air intake temperature sensor 1116 is used for measuring the temperature of the intake air of the intake module and feeding back a corresponding temperature signal; the air intake flow sensor 1117 is configured to measure a flow rate of air and to feed back a corresponding flow rate signal.

The air intake pressure sensor 1115 and the air intake temperature sensor 1116 may be sensors that are separately disposed or may be integrated into a single measuring probe and output pressure and temperature signals, respectively.

The air intake and exhaust system further comprises an FCU (Fuel-cell Control Unit) system 116, the FCU system 116 is configured to receive signals fed back by components (such as an air intake pressure sensor 1115, an air intake temperature sensor 1116, an air intake flow sensor 1117, a driving motor 1112, etc.) in the Fuel cell 1 and send control instructions according to the signals to control the Fuel cell 1, and an atmospheric pressure sensor 1161 and an atmospheric temperature sensor 1162 may be disposed inside or outside the FCU system 116 to detect the atmospheric pressure and the environmental temperature of the location of the Fuel cell 1, and the FCU system 116 may be configured to detect and manage the working state and the safety failure of the Fuel cell 1, so as to ensure that the Fuel cell 1 has good working performance and safety.

In other embodiments of the present invention, a tail pipe 1126 and a tail pipe muffler 1127 are disposed between the exhaust outlet of the exhaust module and the outside, high-pressure exhaust gas energy absorbed and utilized by the exhaust turbine 1121 and a small amount of hydrogen discharged from the anode side of the fuel cell 1 may enter the tail pipe 1126 and be mixed and diluted in the tail pipe 1126 to enhance environmental protection discharged into the outside environment or other devices, and the tail pipe muffler 1127 is disposed on the tail pipe 1126 and is used for reducing or eliminating exhaust noise.

As shown in fig. 1 and 2, according to some embodiments of the invention, energy recovery device 1122 is configured as a generator that is electrically connected to at least drive motor 1112.

Specifically, the energy recovery device 1122 is configured as a generator, the exhaust turbine 1121 is driven to rotate by the kinetic energy and heat energy of the gas of the high-pressure exhaust gas during working, the generator can convert the rotary mechanical energy of the second drive shaft 1123 into electric energy, and the electric energy in the generator can be at least electrically connected with the driving motor 1112 through the arrangement of the generator, so that the electric energy in the generator can be used for the driving motor 1112, other electric equipment 15 and energy storage equipment, and the originally wasted high-pressure exhaust gas energy can be recovered, so that the energy consumption of the fuel cell 1 is reduced, the economy and the environmental friendliness are better, and meanwhile, the generator provides more electric energy for the driving motor 1112, the other electric equipment 15 and the energy storage equipment, thereby being beneficial to improving the working efficiency and the power density of the fuel cell 1.

It should be noted that the other electric devices 15 and the energy storage devices described above may be internal devices of the fuel cell 1, such as the driving motor 1112, the hydrogen circulation pump for the anode gas system in the fuel cell 1, etc., but are not limited to only the internal devices of the fuel cell 1, but may also be devices other than the fuel cell 1, such as a main driving motor controller on a vehicle provided with the fuel cell 1, a water pump of a water thermal management system, and the high-voltage battery 14, etc.

Furthermore, in some embodiments of the present invention, the generator is configured as a permanent magnet synchronous motor, an induction motor, or other type of high speed motor to enhance the performance of the generator.

In some embodiments, the exhaust module further includes a generator inverter 11221, the generator inverter 11221 has a generator inverter 11221 power input interface and a generator inverter 11221 power output interface for power input and power output, respectively, the generator inverter 11221 power input interface is connected to the power interface of the generator, the generator converts the rotational mechanical energy into electric energy, and the electric energy output form thereof is high-voltage high-frequency alternating current, and the generator inverter 11221 can convert the high-voltage high-frequency alternating current into high-voltage direct current through its internal high-power semiconductor components, and directly use the electric equipment 15 and the energy storage device through the generator inverter 11221 power output interface, thereby improving the electric safety.

Further, the driving motor 1112 includes a motor controller 11121, where the motor controller 11121 can convert the high-voltage direct current into high-voltage high-frequency alternating current through a high-power semiconductor component to drive the first driving shaft 1113 to rotate, and the motor controller 11121 can regulate the rotation speed and power of the air compressor 1111 through the first driving shaft 1113 according to the instruction of the FCU system 116 and send the running state to the FCU system 116 in real time. The motor controller 11121 has a motor controller 11121 power input interface, and the motor controller 11121 power input interface can be electrically connected with a generator inverter 11221 power output interface to obtain operating power.

The motor controller 11121 may be integrated into the air compressor 1111 to form a whole machine with the air compressor 1111 to improve compactness and power density, and the motor controller 11121 may also be integrated into a DC/DC (Direct Current/Direct Current) system 13 described below to improve compactness and EMC (Electro Magnetic Compatibility ) performance of the power connection and reduce cost; similarly, the generator inverter 11221 may be integrated into the generator or the DC/DC system 13, or the motor controller 11121 may be integrated with the generator inverter 11221 or both into the DC/DC system 13.

Preferably, in some embodiments of the present invention, the generator inverter 11221 uses high-frequency low-power high-power semiconductor components such as silicon carbide, insulated gate bipolar transistor or gallium nitride to convert high-frequency ac power into high-voltage dc power, and the motor controller 11121 uses high-frequency low-power high-power semiconductor components such as silicon carbide, insulated gate bipolar transistor or gallium nitride to convert high-voltage dc power into high-voltage high-frequency ac power, so as to improve the operation performance of the generator inverter 11221, save cost and save power consumption.

As shown in fig. 1 and 2, the air compressor 1111 is configured as a single-stage air compressor or a multi-stage air compressor according to some embodiments of the present invention.

Specifically, the single-stage air compressor has a single-stage compression function, air is compressed once by the single-stage air compressor to obtain required gas, the multi-stage air compressor has a multi-stage compression function, air is compressed twice or more times by the multi-stage air compressor to obtain required gas, the multi-stage air compressor has higher air compression strength than the single-stage air compressor, and the air compressor 1111 is constructed as the single-stage air compressor or the multi-stage air compressor, so that the compression strength of the air compressor 1111 can be adapted to the working requirement of the fuel cell 1 to obtain high-pressure cathode gas suitable for electrochemical reaction of the electric pile 12, and the balance between the working performance and the economic cost of the fuel cell 1 can be realized.

As shown in fig. 1 and 2, in some embodiments, the air compressor 1111 is configured as a dual-stage air compressor, and the low-pressure side impeller 11111 and the high-pressure side impeller 11112 are located at axial ends of the first drive shaft 1113.

Specifically, the high-pressure side impeller 11112 is located at an end of the first driving shaft 1113 near the air inlet 12a of the electric pile 12, the low-pressure side impeller 11111 is located at an end of the first driving shaft 1113 far away from the air inlet 12a of the electric pile 12, when the first driving shaft 1113 rotates, the low-pressure side impeller 11111 and the high-pressure side impeller 11112 can be driven to rotate at the same rotation speed, the low-pressure side impeller 11111 rotates to perform primary compression on air entering the air inlet module, an inter-stage pipeline 11113 for air circulation can be arranged between the low-pressure side impeller 11111 and the high-pressure side impeller 11112, and the high-pressure side impeller 11112 rotates to perform secondary compression on air flowing out of the inter-stage pipeline 11113, so that a dual-stage compression function of the dual-stage air compressor is achieved. The arrangement mode that the low-pressure side impeller 11111 and the high-pressure side impeller 11112 are arranged at the two axial ends of the first driving shaft 1113 can promote the integration of the low-pressure side impeller 11111 and the high-pressure side impeller 11112, is beneficial to the volume optimization of the two-stage air compressor, and saves the installation space; on the other hand, partial acting forces generated in the process of compressing air by the low-pressure side impeller 11111 and the high-pressure side impeller 11112 can be mutually offset, so that at least partial axial force of the first driving shaft 1113 forms a balanced state, thereby reducing the stress of a thrust component for axial support in the two-stage air compressor, improving the reliability of the thrust component and prolonging the service life of the two-stage air compressor.

It should be noted that, the low-pressure side impeller 11111 and the high-pressure side impeller 11112 may be configured as centrifugal impellers in radial, mixed-flow, axial-flow or other forms, so as to achieve a wide air-air characteristic map after compression, and have a strong altitude compensation capability, so that the working performance of the air compressor 1111 may be optimized.

Furthermore, in some embodiments of the present invention, low pressure side impeller 11111 and high pressure side impeller 11112 may be disposed within a low pressure stage housing and a high pressure stage housing, respectively, or may be disposed within the same housing to further enhance integration, and inter-stage piping 11113 between low pressure side impeller 11111 and high pressure side impeller 11112 may be disposed inside or outside the housing.

In other embodiments of the present invention, the first driving shaft 1113 is further provided with a thrust bearing 1118 and a radial bearing 1119, wherein the thrust bearing 1118 may provide axial force support generated by aerodynamic forces of the high pressure side impeller 11112 and the low pressure side impeller 11111 during two-stage air compression, the radial bearing 1119 is configured to be two and located between the high pressure side impeller 11112 and the low pressure side impeller 11111, and the radial bearing 1119 may provide support for self gravity of the first driving shaft 1113 component assembly and unbalanced force during rotation thereof, so that by providing the thrust bearing 1118 and the radial bearing 1119, operational stability and reliability of the first driving shaft 1113 and the air compressor 1111 may be improved, and service lives of the first driving shaft 1113 and the air compressor 1111 may be advantageously prolonged.

Further, to avoid poisoning and ensure long life operation of the stack 12 of the fuel cell 1, the air compressor 1111 providing the high pressure cathode gas may be of oil-free design, and correspondingly, the thrust bearing 1118, the radial bearing 1119 may be configured as a dynamic pressure, static pressure, dynamic and static pressure air bearing or a magnetic suspension, as well as other types of oil-free bearings. Wherein, when an air bearing is adopted, the compressed air required by the operation of the air bearing can be obtained from the interstage pipeline 11113, so that the operation convenience of the air bearing is improved.

As shown in fig. 1 and 2, according to some embodiments of the invention, the air intake module further includes: and a bypass branch 1124, one end of the bypass branch 1124 is connected to the air compressor outlet 1111a of the air compressor 1111, and the other end is connected to the turbine inlet 1121a of the exhaust turbine 1121.

Specifically, after the air flowing out from the air compressor air outlet 1111a is used for electrochemical reaction of the electric pile 12, the high-pressure exhaust gas of the electric pile 12 is recycled by the exhaust turbine 1121 and the energy recovery device 1122 to be a first gas passage in the air intake and exhaust system, and two ends of the bypass branch 1124 are respectively connected with the air compressor air outlet 1111a and the turbine air inlet 1121a, that is, the bypass branch 1124 is connected in parallel with the first gas passage.

Further, when the stack 12 of the fuel cell 1 generates electricity at low power or is cold started at low temperature, the expansion ratio is low, under this condition, a part of the compressed air flowing out from the air outlet 1111a of the air compressor flows into the stack 12, and another part of the compressed air flows into the bypass branch 1124 and enters the exhaust turbine 1121 through the turbine inlet 1121a after flowing through the bypass branch 1124, so that the energy conversion of the stack 12 can be ensured, and the exhaust turbine 1121 can utilize the expansion of the gas formed by mixing the compressed air and the high-pressure exhaust gas to do work, so as to improve the energy efficiency of the exhaust turbine 1121 and the energy recovery device 1122; when the fuel cell 1 is in a normal power generation state, the compressed air flowing out from the air outlet 1111a of the air compressor flows only to the pile 12 for electrochemical reaction, so as to ensure that the energy of the high-pressure exhaust gas is fully recovered by the exhaust turbine 1121 and the energy recovery device 1122, thereby saving energy loss and improving environmental protection.

As shown in fig. 1 and 2, in some embodiments, bypass branch 1124 includes: an inlet line, a bypass valve 1125, and an outlet line, which are in communication in sequence.

Wherein, the inlet pipeline is communicated with an air outlet 1111a of the air compressor, and the outlet pipeline is connected with a turbine air inlet 1121 a.

Specifically, the bypass valve 1125 is disposed between the inlet pipeline and the outlet pipeline, and selectively opens the bypass branch 1124, when the bypass valve 1125 opens the bypass branch 1124, part of the compressed air flowing out from the air outlet 1111a of the air compressor flows into the bypass branch 1124 through the inlet pipeline and flows into the turbine air inlet 1121a through the outlet pipeline, so that the exhaust turbine 1121 drives the energy recovery device 1122 through the second driving shaft 1123 for use, and thus, according to different power generation power and working conditions of the fuel cell 1, the bypass valve 1125 can correspondingly control the opening and closing of the bypass branch 1124, so that the exhaust turbine 1121 and the air compressor 1111 can always have good working performance, and comprehensive energy efficiency and output power of the fuel cell 1 are improved.

As shown in fig. 1 and 2, according to some embodiments of the present invention, a turbine wheel 11211 and an adjustable turbine nozzle 11212 are disposed within a turbine housing of an exhaust turbine 1121 and adapted to effect flow area adjustment of the exhaust turbine 1121 by adjusting a nozzle aperture of the adjustable turbine nozzle 11212.

Specifically, after the gas enters the turbine housing of the exhaust turbine 1121 through the turbine inlet 1121a, the gas may be applied to the turbine wheel 11211 and the adjustable turbine nozzle 11212, respectively, so as to recover kinetic energy and thermal energy of the gas through expansion work, and the rotating machine recovered by the turbine wheel 11211 may be transferred to the energy recovery device 1122 through the second driving shaft 1123 for power generation. By adjusting the nozzle aperture of the adjustable turbine nozzle 11212, the flow area of the exhaust turbine 1121 can be changed, and the pressure and flow of the gas entering and exiting the stack 12 can be adjusted, so that the adaptability of the exhaust turbine 1121 to stacks 12 with different target performances can be improved, and the working efficiency of the exhaust turbine 1121 can be improved adaptively.

For the exhaust turbine 1121 with an adjustable structure, in one embodiment of the present invention, the adjustable turbine nozzle 11212 is provided with an adjustable turbine nozzle electric actuator 11213, and the adjustable turbine nozzle electric actuator 11213 can receive a control command sent by the FCU system 116 and adjust the flow area of the gas of the adjustable turbine nozzle 11212 according to the received control command, so as to improve the adjustment flexibility and automation of the exhaust turbine 1121.

In other embodiments, the exhaust turbine 1121 may also adopt a non-adjustable structure, and the flow characteristic of the exhaust turbine 1121 with a fixed section may also realize the following adjustment of the pressure and flow of the gas into and out of the stack 12, so that the overall structure of the fuel cell 1 is simpler, the operation is more reliable, and the cost is lower while the power generation requirement of the fuel cell 1 and the high-pressure exhaust energy recovery are met.

Preferably, in some embodiments, the turbine wheel 11211 is configured as a radial, mixed flow, axial flow, or other form of centrifugal turbine to meet the expansion ratio and flow-through characteristics of the different high pressure exhaust gases flowing through the exhaust turbine 1121, thereby achieving a high isentropic efficiency boost of recovered energy.

In an embodiment of the present invention, the turbine wheel 11211 may be formed by a wheel disc and a plurality of blades mounted thereon, where the wheel disc is connected to the second driving shaft 1123, and the high-pressure gas entering the turbine housing expands to perform work to rotate the blades and the wheel disc, so as to drive the second driving shaft 1123 to rotate to realize the driving energy recovery device 1122.

In order to enhance the operational stability of the exhaust turbine 1121 and the second driving shaft 1123, the turbine bearing 11214 may be disposed on the second driving shaft 1123 to support the axial force generated by the turbine impeller 11211, the self-gravity of the assembly of the exhaust turbine 1121 and the second driving shaft 1123, and the unbalanced force during the rotation process thereof, so as to enhance the operational stability and reliability of the exhaust turbine 1121 and the second driving shaft 1123, and facilitate the extension of the service lives of the second driving shaft 1123 and the exhaust turbine 1121.

Since the exhaust turbine 1121 and the energy recovery device 1122 are located at the downstream section between the exhaust port 12b of the stack 12 and the outside, the flow direction of the gas from the exhaust turbine 1121 and the energy recovery device 1122 is from the stack 12, and therefore, the use of the ball bearing containing grease for the turbine bearing 11214 does not pollute the stack 12, and the ball bearing has the advantage of no take-off speed limitation, so that the exhaust turbine 1121 and the energy recovery device 1122 can operate at low speeds, the operating range of the exhaust turbine 1121 and the energy recovery device 1122 for energy recovery power generation is expanded, and the operating efficiency of the exhaust turbine 1121 and the energy recovery device 1122 at low expansion ratios of the fuel cell 1 is improved, and the cost and energy consumption are saved.

Furthermore, in one embodiment of the present invention, a turbine housing temperature sensor 11215 may be provided on the turbine housing to cooperate with the FCU system 116 to improve the operating efficiency and reliability of the exhaust turbine 1121.

As shown in fig. 1 and 2, the intake and exhaust system further includes an intercooler 113 and a humidifier 114 according to some embodiments of the present invention.

Wherein, the inlet of the intercooler 113 is connected with the air compressor air outlet 1111a, the outlet of the intercooler 113 is connected with the dry inlet end 114a of the humidifier 114, the dry outlet end 114b of the humidifier 114 is connected with the air inlet 12a, the wet inlet end 114c of the humidifier 114 is connected with the air outlet 12b, and the wet outlet end 114d of the humidifier 114 is connected with the turbine air inlet 1121 a.

Specifically, the inlet of the intercooler 113 is connected to the air compressor air outlet 1111a, the high-temperature and high-pressure gas compressed by the air compressor 1111 can flow into the intercooler 113 through the air compressor air outlet 1111a and the intercooler 113 inlet in sequence, the intercooler 113 can cool down the high-temperature and high-pressure gas through a cooling medium to meet the requirement of electrochemical reaction of the electric pile 12 on the high-pressure cathode gas temperature, the cooled down gas can enter the humidifier 114 through the outlet of the intercooler 113 through the dry inlet end 114a of the humidifier 114, the wet inlet end 114c of the humidifier 114 is connected to the air outlet 12b of the electric pile 12, the humidifier 114 can humidify the dry air entering the humidifier 114 through the dry inlet end 114a by utilizing the wet air discharged from the air outlet 12b to meet the humidity requirement of the electric pile 12 on the high-pressure cathode gas, meanwhile, the wet air entering the humidifier 114 through the wet inlet end 114c of the humidifier 114 (i.e. the high-pressure exhaust gas discharged from the air outlet 12b of the electric pile 12) can enter the humidifier 114 through the wet outlet end 114d of the turbine air inlet 1121a, thereby realizing good efficiency of the electric pile 12 and energy saving of the electric pile 12 and further optimizing the energy consumption of the electric pile 1.

It should be noted that the cooling medium may be, but is not limited to, methanol solution, ethanol solution or water.

Preferably, in one embodiment of the present invention, the humidifier 114 is configured as a membrane-tube-type or enthalpy-wheeled humidifier 114, and the membrane-tube-type or enthalpy-wheeled humidifier 114 has high working efficiency, good safety performance, energy saving and environmental protection, and helps to further improve the overall working efficiency, reliability and environmental protection of the fuel cell 1.

In some embodiments, a pile-in air pressure sensor 117 and a pile-in air temperature sensor 118 are disposed between the dry outlet end 114b of the humidifier and the air inlet 12a of the electric pile 12, and the pile-in air pressure sensor 117 and the pile-in air temperature sensor 118 are respectively used for measuring the pressure and temperature of the high-pressure cathode gas entering the electric pile 12, and feeding back corresponding pressure and temperature signals to the FCU system 116 to ensure detection and control of the operation of the electric pile 12. Similarly, the in-stack air pressure sensor 117 and the in-stack air temperature sensor 118 may be separately disposed sensors or may be integrated into one measurement probe but output pressure and temperature signals, respectively.

In addition, in other embodiments, the requirements of the stack 12 on humidity can be satisfied by the self-humidification of the interior of the stack 12 for some stacks 12 of the fuel cell 1 with self-humidification, in which case the humidifier 114 may not be additionally provided to save cost.

As shown in fig. 2, in some embodiments, the air intake and exhaust system further includes a heat exchanger 115, an inlet of the heat exchanger 115 is connected to the air compressor air outlet 1111a, an outlet of the heat exchanger 115 is connected to an inlet of the intercooler 113, the heat exchanger 115 further has an exhaust gas inlet 115a and an exhaust gas outlet 115b, the exhaust gas inlet 115a is connected to the wet outlet end 114d, the exhaust gas outlet 115b is connected to the turbine air inlet 1121a, and the intercooler 113 is formed as a water-cooled intercooler 113 and further has a cooling medium inlet 113a and a cooling medium outlet 113b.

Specifically, the inlet of the heat exchanger 115 is connected to the air compressor outlet 1111a, after compressed air flows out from the air compressor outlet 1111a, the compressed air can flow into the heat exchanger 115 from the inlet of the heat exchanger 115, and the exhaust gas inlet 115a of the heat exchanger 115 is connected to the wet outlet 114d of the humidifier 114, after the high-pressure exhaust gas discharged from the exhaust port 12b of the electric pile 12 enters the humidifier 114 from the wet inlet 114c of the humidifier 114, the high-pressure exhaust gas can enter the heat exchanger 115 from the wet outlet 114d of the humidifier 114 through the exhaust gas inlet 115a, so that the high-temperature compressed air can transfer heat into the high-humidity high-pressure exhaust gas with relatively low temperature in the heat exchanger 115, and the high-pressure exhaust gas can be heated while reducing the temperature of the compressed air, and the relative humidity and condensation temperature in the high-pressure exhaust gas are reduced according to the principle of change of enthalpy and humidity of the wet air, so that the liquid water particle size in the high-pressure exhaust gas is reduced or is not visible, on one hand, the impact of the high-pressure exhaust gas on the exhaust turbine 1121 due to the excessive liquid water content can be avoided, and the reliability and service life of the exhaust turbine 1121 can be further improved; on the other hand, after the high-pressure exhaust gas is heated, the energy recovered by the exhaust turbine 1121 and the energy recovery device 1122 can be increased, and the efficiency and the economy of the fuel cell 1 can be further improved.

It can be appreciated that the heat exchanger 115 plays a role in separating gas from liquid for high-pressure exhaust gas, so that the gas inlet and outlet system in the embodiment of the invention does not need to additionally arrange a gas-liquid separator, thereby saving space and cost, and avoiding energy leakage caused by adopting the gas-liquid separator, thereby saving energy.

In the embodiment of the invention, the outlet of the heat exchanger 115 is connected with the inlet of the intercooler 113, the cooling liquid can enter and exit the intercooler 113 through the cooling medium inlet 113a and the cooling medium outlet 113b, the compressed air can flow into the intercooler 113 through the outlet of the heat exchanger 115 and the inlet of the intercooler 113 in sequence, and exchange heat with the cooling liquid to realize cooling, and because the compressed air exchanges heat with high-pressure waste gas in the heat exchanger 115 to realize good cooling, the target performance requirement of the intercooler 113 can be reduced, the requirement on the temperature regulation of the high-pressure cathode gas entering the electric pile 12 can be met by selecting the intercooler 113 with a small size, thus the burden of a hydro-thermal system of the fuel cell 1 can be reduced, the efficiency of the fuel cell 1 is improved, and the cost and the arrangement occupation space of the intercooler 113 are saved.

It should be noted that the intercooler 113 may be configured as a water-cooled intercooler 113, i.e., the cooling liquid is water, so as to improve environmental protection and save cost.

Furthermore, in some embodiments, the heat exchanger 115 and the intercooler 113 may be integrated as a unitary component to reduce installation size and pipeline energy loss, thereby improving the overall compactness of the intake and exhaust system and the power density of the fuel cell 1.

As shown in fig. 1 and 2, a fuel cell 1 according to an embodiment of the second aspect of the invention, the fuel cell 1 includes: pile 12, intake and exhaust system and DC/DC system 13.

The stack 12 is a device for performing electrochemical reaction on high-pressure cathode gas and anode gas and generating power, the stack 12 may be formed by stacking a plurality of single cells through a certain process, the air inlet and outlet system is configured as the air inlet and outlet system according to any one of the above embodiments, the air inlet module is connected to the air inlet 12a of the stack 12, the air outlet module is connected to the air outlet 12b of the stack 12, the air inlet module may provide the stack 12 with the required high-pressure cathode gas, the air outlet module may guide the high-pressure exhaust gas after the electrochemical reaction of the stack 12 to the exhaust turbine 1121 for recycling energy of the high-pressure exhaust gas, the DC/DC system 13 is electrically connected to the stack 12, and the DC/DC system 13 may convert the low-voltage and unstable direct current generated by the stack 12 into a stable voltage value and output the stable voltage value to the power supply device 15 and the energy storage device.

It can be appreciated that the DC/DC system 13 can transmit power to the electric devices 15 and the energy storage devices in the fuel cell 1 and outside the fuel cell 1 through the high-voltage DC bus, for example, the driving motor 1112, the high-voltage battery 14, and the like, and part of the power of the DC/DC system 13 can be derived from the energy recovery device 1122, and the output power of the energy recovery device 1122 at the maximum generated power is smaller than that of the driving motor 1112 and the DC/DC system 13, i.e. the ratio of the power to the total power consumption and the power supply capacity is smaller, so that the impact and the influence on the high-voltage DC bus are not caused, and the energy recovered by the exhaust turbine 1121 and the energy recovery device 1122 can be simultaneously used by all the electric devices 15 in real time, thereby effectively improving the power supply flexibility and convenience.

It should be noted that the fuel cell 1 disclosed in the embodiment of the present invention may be used in, but not limited to, electric devices such as vehicles, ships or aircrafts. The power supply system comprising the pile 12, the air intake and exhaust system, the DC/DC system 13 and the like can be used, so that the application range of the fuel cell 1 is enlarged, and the energy efficiency of the power utilization device is improved.

In summary, the fuel cell according to the embodiment of the present invention includes the stack 12, the air intake and exhaust system, the DC/DC system 13, the anode gas system, the water thermal management system, the control system, and the like, where the air intake and exhaust system according to the first aspect of the present invention includes the air compressor 1111, the driving motor 1112, the first driving shaft 1113, the bypass branch 1124, the exhaust turbine 1121, the energy recovery device 1122, the second driving shaft 1123, the intercooler 113, the humidifier 114, and the FCU system 116, and the like, and the air intake and exhaust system according to the second aspect of the present invention adds the heat exchanger 115 on the basis of the air intake and exhaust system according to the first aspect of the present invention, and the first driving shaft 1113 and the second driving shaft 1123 are separately arranged, so that the following technical effects are mainly obtained: firstly, the air compressor 1111 and the exhaust turbine 1121 are relatively independent components, and are not limited by the same physical rotation speed, the air compressor 1111 can be arranged to operate in a higher aerodynamic isentropic efficiency area, which is beneficial to reducing parasitic power consumption of an air intake and exhaust system and improving operational reliability and economy of the fuel cell 1; secondly, the exhaust turbine 1121 and the energy recovery device 1122 can perform optimization matching design on the specific speed and the through-flow capacity according to the characteristic of the high-pressure exhaust gas energy of the electric pile 12 of the fuel cell 1, especially under the working conditions of low expansion ratio and high flow, so that the electric pile 12 can be recycled to obtain the highest isentropic efficiency of the turbine by running at the optimal speed ratio, thereby obtaining more generated energy and further improving the overall efficiency and the economical efficiency of the fuel cell 1; thirdly, after the structures and the characteristics of the air compressor 1111 and the exhaust turbine 1121 are optimized, the bearing is stressed less and more balanced in the application scene of low expansion ratio, so that the reliability and the service life of the bearing are improved, and the maintenance cost is saved; fourth, the exhaust turbine 1121 and the energy recovery device 1122 can recycle the residual pressure of the waste heat in the high-pressure exhaust gas discharged from the stack 12, and the high-pressure exhaust gas expands and works through the exhaust turbine 1121 to drive the energy recovery device 1122 to generate electricity and output, so that the originally wasted energy of the high-pressure exhaust gas is recovered, the hydrogen consumption of the fuel cell 1 is reduced, and the method has important significance in saving energy and protecting the environment.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

In the description of the invention, a "first feature" or "second feature" may include one or more of such features.

In the description of the present invention, "plurality" means two or more.

In the description of the invention, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact with each other by another feature therebetween.

In the description of the invention, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the invention, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. An intake and exhaust system of a fuel cell, comprising:

an air intake module which communicates with an air intake port (12 a) of a stack (12) of the fuel cell and is configured to supply high-pressure cathode gas to the stack (12), the air intake module including an air compressor (1111) and a driving motor (1112), the driving motor (1112) driving the air compressor (1111) through a first driving shaft (1113);

the exhaust module is communicated with an exhaust port (12 b) of the electric pile (12) and is used for exhausting high-pressure exhaust gas in the electric pile (12), the exhaust module comprises an exhaust turbine (1121) and an energy recovery device (1122), the exhaust turbine (1121) drives the energy recovery device (1122) through a second driving shaft (1123), and the first driving shaft (1113) and the second driving shaft (1123) are arranged at intervals.

2. The fuel cell air intake and exhaust system according to claim 1, wherein the energy recovery device (1122) is configured as a generator, which is electrically connected to at least the drive motor (1112).

3. The air intake and exhaust system of the fuel cell according to claim 1, characterized in that the air compressor (1111) is configured as a single-stage air compressor or a multi-stage air compressor.

4. A fuel cell intake and exhaust system according to claim 3, wherein the air compressor (1111) is configured as a two-stage air compressor, and a low-pressure side impeller (11111) and a high-pressure side impeller (11112) are located at both axial ends of the first drive shaft (1113).

5. The air intake and exhaust system of the fuel cell according to claim 1, wherein the air intake module further comprises: and one end of the bypass branch (1124) is connected with an air outlet (1111 a) of the air compressor (1111), and the other end of the bypass branch (1124) is connected with a turbine air inlet (1121 a) of the exhaust turbine (1121).

6. The fuel cell intake and exhaust system according to claim 5, wherein the bypass branch (1124) includes: the inlet pipeline, the bypass valve (1125) and the outlet pipeline which are communicated in sequence, wherein the inlet pipeline is communicated with the air outlet (1111 a) of the air compressor, and the outlet pipeline is connected with the air inlet (1121 a) of the turbine.

7. The fuel cell intake and exhaust system according to claim 1, characterized in that a turbine wheel (11211) and an adjustable turbine nozzle (11212) are provided in a turbine housing of the exhaust turbine (1121), and that the flow area of the exhaust turbine (1121) is adjusted by adjusting the nozzle aperture of the adjustable turbine nozzle (11212).

8. The air intake and exhaust system of a fuel cell according to claim 1, further comprising an intercooler (113) and a humidifier (114), wherein an inlet of the intercooler (113) is connected to an air compressor air outlet (1111 a), an outlet of the intercooler (113) is connected to a dry inlet end (114 a) of the humidifier (114), a dry outlet end (114 b) of the humidifier (114) is connected to the air inlet (12 a), a wet inlet end (114 c) of the humidifier (114) is connected to the air outlet (12 b), and a wet outlet end (114 d) of the humidifier (114) is connected to a turbine air inlet (1121 a).

9. The fuel cell intake and exhaust system according to claim 8, further comprising: the heat exchanger (115), heat exchanger (115) import with air compressor machine gas outlet (1111 a) links to each other, heat exchanger (115) export with intercooler (113) import links to each other, heat exchanger (115) still have waste gas inlet port (115 a) and exhaust gas outlet (115 b), waste gas inlet port (115 a) with wet exit end (114 d) links to each other, exhaust gas outlet (115 b) with turbine air inlet (1121 a) links to each other, intercooler (113) is formed as water-cooled intercooler (113) and still has cooling medium import (113 a) and cooling medium export (113 b).

10. A fuel cell, characterized by comprising:

a galvanic pile (12);

the air intake and exhaust system of any of claims 1-9, the air intake module being connected to an air intake (12 a) of the stack (12), the air exhaust module being connected to an air exhaust (12 b) of the stack (12);

-a DC/DC system (13), said DC/DC system (13) being electrically connected to said stack (12).