阅读说明：本技术 燃料电池系统及其控制方法 (Fuel cell system and control method thereof ) 是由 刘亚坤 原瑞 徐佳 A·瓦萨帕那瓦拉 崔天宇 于 2020-04-30 设计创作，主要内容包括：本发明公开了一种燃料电池系统及其控制方法,所述燃料电池系统包括：电堆、储料罐、喷射阀；所述储料罐内存储有燃料,所述储料罐与所述电堆的阳极通过引射器连通；所述喷射阀为多个,所述喷射阀的一端与所述储料罐连通,另一端与所述引射器连通,每个所述喷射阀均构造为开关阀,以控制所述燃料罐与所述引射器在连通的导通状态和闭合的断开状态之间切换。由此,一方面,使喷射阀在燃料电池系统处于任意工作状态时,均可以提供初始动能较高、压力较高的工作流体,以满足燃料电池系统对燃料过量系数的要求；另一方面,无需设置循环泵,可以降低燃料电池系统的生产成本,同时降低寄生功率,可以有效地提高燃料电池系统的能量利用率。(The invention discloses a fuel cell system and a control method thereof, the fuel cell system includes: the device comprises a galvanic pile, a storage tank and an injection valve; fuel is stored in the storage tank, and the storage tank is communicated with the anode of the galvanic pile through an ejector; the injection valves are multiple, one end of each injection valve is communicated with the storage tank, the other end of each injection valve is communicated with the ejector, and each injection valve is constructed as a switch valve to control the fuel tank and the ejector to be switched between a communicated conduction state and a closed disconnection state. Therefore, on one hand, when the fuel cell system is in any working state, the injection valve can provide working fluid with high initial kinetic energy and high pressure so as to meet the requirement of the fuel cell system on the fuel excess coefficient; on the other hand, a circulating pump is not needed, so that the production cost of the fuel cell system can be reduced, the parasitic power is reduced, and the energy utilization rate of the fuel cell system can be effectively improved.)

1. A fuel cell system (100), comprising:

a galvanic pile (10);

the fuel storage tank (20) is used for storing fuel, and the fuel storage tank (20) is communicated with the anode (11) of the electric pile (10) through an ejector (94);

the injection valves (30) are multiple, one end of each injection valve (30) is communicated with the storage tank (20), the other end of each injection valve is communicated with the ejector (94), and each injection valve (30) is constructed as a switch valve to control the storage tank (20) and the ejector (94) to be switched between a communicated conduction state and a closed disconnection state.

2. The fuel cell system (100) according to claim 1, wherein the fuel cell system (100) further comprises: the inlet of the gas-liquid separator (50) is communicated with the reflux port of the anode (11), the liquid outlet of the gas-liquid separator (50) is communicated with the drain valve (52), and the gas outlet of the gas-liquid separator (50) is communicated with the exhaust valve (53) and the ejector (94).

3. The fuel cell system (100) according to claim 2, wherein the fuel cell system (100) further comprises: a first controller (91), the first controller (91) being adapted to control an open-close cycle of the injection valve (30) in accordance with an intake pressure of an anode (11).

4. The fuel cell system (100) according to claim 3, wherein the fuel cell system (100) further comprises: a second controller (92), the second controller (92) being adapted to control an open-close cycle of the injection valve (30) in accordance with a fuel concentration at an intake end of the anode (11).

5. The fuel cell system (100) according to claim 4, wherein the first controller (91) and the second controller (92) comprehensively control the open-close cycle of the plurality of injection valves (30).

6. The fuel cell system (100) of claim 4, wherein a plurality of the injection valves (30) are disposed in parallel between the accumulator tank (20) and the ejector (94).

7. The fuel cell system (100) according to claim 6, wherein the fuel cell system (100) further comprises: the proportional electromagnetic valve (95), the one end of proportional electromagnetic valve (95) with storage tank (20) intercommunication, the other end of proportional electromagnetic valve (95) with the inlet end intercommunication of ejector (94), proportional electromagnetic valve (95) with injection valve (30) parallel arrangement.

8. The fuel cell system (100) according to claim 7, further comprising: a third controller (93), the third controller (93) being adapted to control the opening degree of the proportional solenoid valve (95) according to the intake pressure of the anode (11).

9. A control method of a fuel cell system (100), characterized in that the fuel cell system (100) is the fuel cell system (100) of claim 8;

the control method comprises the following steps:

s1: the first controller (91) acquires a first period according to the intake pressure of the anode (11) and the set pressure of the anode (11);

s2: the second controller (92) acquires a second period according to the opening degree of the exhaust valve (53);

s3: the opening and closing period of each injection valve (30) is adjusted according to the first period and the second period.

10. The control method of a fuel cell system (100) according to claim 9, characterized in that the control method further comprises:

a1: the third controller (93) acquires a third period according to the intake pressure of the anode (11) and the set pressure of the anode (11);

a2: and adjusting the duty ratio of the proportional solenoid valve (95) according to the third period.

Technical Field

The invention relates to the technical field of fuel cells, in particular to a fuel cell system and a control method thereof.

Background

In the related art, fuel stored in a storage tank is supplied in a gaseous form to an anode of a stack of a fuel cell through an injection valve. In the stack the fuel reacts with the oxidant supplied to the cathode to convert chemical energy into electrical energy. The fuel remaining after the reaction is recirculated to the intake end of the anode through a circulation pump and an ejector. The use of a circulation pump increases the cost and weight of the fuel cell system.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. To this end, an object of the present invention is to provide a fuel cell system which is smaller, lower in cost, simple to control, and high in energy utilization.

The invention further provides a control method of the fuel cell system.

A fuel cell system according to an embodiment of the first aspect of the invention includes: the device comprises a galvanic pile, a storage tank and an injection valve; fuel is stored in the storage tank, and the storage tank is communicated with the anode of the galvanic pile through an ejector; the injection valves are multiple, one end of each injection valve is communicated with the storage tank, the other end of each injection valve is communicated with the ejector, and each injection valve is constructed as a switch valve to control the fuel tank and the ejector to be switched between a communicated conduction state and a closed disconnection state.

According to the fuel cell system disclosed by the embodiment of the invention, the existing proportional valve with adjustable opening degree is replaced by the injection valve which can be switched between the on state and the off state, so that on one hand, when the fuel cell system is in any working state, the injection valve can provide working fluid with higher initial kinetic energy and higher pressure, and the requirement of the fuel cell system on the fuel excess coefficient is met; on the other hand, a circulating pump is not needed, so that the production cost of the fuel cell system can be reduced, the weight of the fuel cell system is reduced, the parasitic power is reduced, and the energy utilization rate of the fuel cell system can be effectively improved.

According to some embodiments of the invention, the fuel cell system further comprises: and the inlet of the gas-liquid separator is communicated with the reflux port of the anode, the liquid outlet of the gas-liquid separator is communicated with the drain valve, and the gas outlet of the gas-liquid separator is communicated with the exhaust valve and the ejector.

Further, the fuel cell system further includes: a first controller adapted to control an open-close cycle of the injection valve in accordance with an intake pressure of the anode.

Further, the fuel cell system further includes: a second controller adapted to control an open-close cycle of the injection valve in accordance with a fuel concentration of an intake end of the anode.

Further, the first controller and the second controller comprehensively control the open-close period of the plurality of injection valves.

According to some embodiments of the invention, a plurality of the injection valves are arranged in parallel between the storage tank and the eductor.

Further, the fuel cell system further includes: and one end of the proportional solenoid valve is communicated with the storage tank, the other end of the proportional solenoid valve is communicated with the air inlet end of the ejector, and the proportional solenoid valve and the injection valve are arranged in parallel.

In some embodiments, the fuel cell system further comprises: a third controller adapted to control an opening degree of the proportional solenoid valve according to an intake pressure of the anode.

A control method of a fuel cell system according to an embodiment of a second aspect of the invention, the control method includes: s1: the first controller acquires a first period according to the inlet pressure of the anode and the set pressure of the anode; s2: the second controller acquires a second period according to the opening degree of the exhaust valve; s3: and adjusting the opening and closing period of each injection valve according to the first period and the second period.

Further, the control method further includes: a1: the third controller obtains a third period according to the inlet pressure of the anode and the set pressure of the anode; a2: and adjusting the duty ratio of the proportional solenoid valve according to the third period.

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 above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic view of a fuel cell system according to the present invention;

fig. 2 is another schematic diagram of a fuel cell system according to the present invention.

Reference numerals:

the fuel cell system 100 is provided with a fuel cell system,

a stack 10, an anode 11, a cathode 12,

a storage tank 20, an injection valve 30, a pressure reducing valve 40,

a gas-liquid separator 50, a liquid level sensor 51, a drain valve 52, a vent valve 53,

cooling module 60, air module 70, high pressure module 80,

a first controller 91, a second controller 92, a third controller 93, an ejector 94 and a proportional solenoid valve 95.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

A fuel cell system 100 and a control method thereof according to an embodiment of the invention are described below with reference to fig. 1 to 2.

As shown in fig. 1 and 2, a fuel cell system 100 according to an embodiment of the first aspect of the invention includes: the galvanic pile 10, the storage tank 20 and the injection valve 30.

Wherein, fuel is stored in the storage tank 20, and the storage tank 20 is communicated with the anode 11 of the electric pile 10 through the ejector 94; the injection valves 30 are plural, one end of the injection valve 30 communicates with the stock tank 20 and the other end communicates with the ejector 94, and each injection valve 30 is configured as an on-off valve to switch between an on state and an off state in which the stock tank 20 communicates with the ejector 94.

Specifically, the fuel in the storage tank 20 can move towards the injector 94 under a certain pressure under the action of the injection valve 30, and then the injector 94 supplies the fuel to the anode 11, and the fuel of the anode 11 reacts with the oxidant of the cathode 12 in the stack 10 to convert the chemical energy of the fuel into electric energy.

In the above working process, based on the characteristic that the ejector 94 does not need to supply energy and has no moving parts inside, during the fuel supply process, the ejector 94 cannot pressurize or push the working fluid to move, the working fluid needs to move towards the anode 11 under the driving of the initial kinetic energy when being ejected by the injection valve 30, and when the fuel cell system 100 is operated in a low-load state, the initial kinetic energy of the recycled fuel (i.e. the fuel in the tail gas after the reaction of the anode 11) is low, and the recycled fuel is difficult to enter the injector 30.

Furthermore, each injection valve 30 is provided as an on-off valve, so that the injection valve 30 can be switched between an on state and an off state, so that the pressure of the working fluid provided by the injection valve 30 is high, the initial kinetic energy is high, and therefore when the fuel cell system 100 is in a low-load operation state, both the fuel provided by the injection valve 30 and the recycled fuel can enter the injection valve 30, so that the fuel excess coefficient of the anode 11 can still be kept stable, and the operation stability of the fuel cell system 100 in the low-load state can be improved.

It should be noted that the storage tank 20 and the ejector 94 mentioned in the present application are communicated, which means that the working fluid can flow from the storage tank 20 to the ejector 94, and the storage tank 20 and the ejector 94 are closed, which means that the storage tank 20 and the ejector 94 are not communicated, and the working fluid cannot flow from the storage tank 20 to the ejector 94.

According to the fuel cell system 100 of the embodiment of the invention, the injection valve 30 which can be switched between the on state and the off state replaces the existing proportional valve with adjustable opening degree, on one hand, when the injection valve 30 is in any working state of the fuel cell system 100, the injection valve 30 can provide working fluid with higher initial kinetic energy and higher pressure, so as to meet the requirement of the fuel cell system 100 on the fuel excess coefficient; on the other hand, a circulation pump is not required, so that the production cost of the fuel cell system 100 can be reduced, the weight of the fuel cell system 100 can be reduced, the parasitic power can be reduced, and the energy utilization rate of the fuel cell system 100 can be effectively improved.

In the particular embodiment shown in fig. 1 and 2, the fuel cell system 100 further includes: and the pressure reducing valve 40, wherein the pressure reducing valve 40 is arranged between the storage tank 20 and the injection valve 30.

The storage tank 20 stores high-pressure gaseous fuel, the fuel entering the anode 11 is gaseous fuel with lower pressure, and the fuel with higher pressure released from the storage tank 20 enters the injector after being reduced in pressure by the pressure reducing valve 40, so that the working stability of the fuel cell system 100 is improved, and the injector or the ejector 94 is prevented from being damaged by the high-pressure fuel.

In some embodiments, the fuel cell system 100 further comprises: and an inlet of the gas-liquid separator 50 is communicated with a return port of the anode 11, a liquid outlet of the gas-liquid separator 50 is communicated with the drain valve 52, and an air outlet of the gas-liquid separator 50 is communicated with the exhaust valve 53 and the ejector 94.

Specifically, tail gas after the anode 11 reaction flows into the gas-liquid separator 50 through the return port, a small amount of liquid water exists in the tail gas, if the liquid water enters the fuel circulation loop, the operation of the electric pile 10 and the ejector 94 is affected, the operation stability of the fuel cell system 100 is reduced, then the liquid water in the tail gas is separated from the residual fuel in the tail gas through the gas-liquid separator 50, and the liquid water can be prevented from entering the ejector 94 or the electric pile 10, so that the operation stability of the fuel cell system 100 is improved.

Meanwhile, it can be understood that during the operation of the fuel cell system 100, liquid water and nitrogen may permeate from the cathode 12 to the anode 11, and the operation stability of the fuel cell system 100 may be further improved by periodically opening and closing the exhaust valve 53. As shown in fig. 1 and 2, a liquid level sensor 50 is disposed within the gas-liquid separator 50, and the liquid level sensor 50 is adapted to control the drain valve 52 to open after the liquid level within the gas-liquid separator 50 exceeds a threshold value. Therefore, the water level in the gas-liquid separator 50 can be prevented from being excessively high, the gas-liquid separator 50 can have a stable gas-liquid separation effect, and the operation stability of the gas-liquid separator 50 can be improved.

As shown in fig. 1 and 2, the fuel cell system 100 further includes: a first controller 91 and a second controller 92, the first controller 91 being adapted to control the open-close period of the injection valve 30 in accordance with the intake pressure of the anode 11; the second controller 91 is adapted to control the open-close period of the injection valve 53 in accordance with the fuel concentration at the intake end of the anode 11.

In this way, by providing the first controller 91, the open/close period of the injection valve 30 can be determined based on the difference between the preset pressure and the intake pressure at the intake end of the actual anode 11, and the second controller 92 determines the open/close period of the injection valve 30 based on the fuel concentration at the intake end (in relation to the opening degree of the exhaust valve 53), thereby controlling the open/close periods of the plurality of injection valves 30 in combination based on the first controller 91 and the second controller 92.

It should be noted that when the exhaust valve 53 is opened, the fuel in the exhaust gas is discharged, and the oxygen concentration at the intake end changes, that is, the opening degree of the exhaust valve 53 is related to the oxygen concentration at the intake end 53.

In one particular embodiment, the first controller 91 is disposed at the inlet end of the anode 11 and the second controller 92 is disposed adjacent to the exhaust valve 53. Therefore, the pressure at the intake end of the anode 11 is obtained by the first controller 91, and the opening degree of the exhaust valve 53 is obtained by the second controller 92 more accurately. Meanwhile, the positions where the first controller 91 and the second controller 92 are provided in the present application are not limited thereto, and are not particularly limited thereto.

That is, in the embodiment shown in fig. 1, the first controller 91 determines which operation state (i.e., on state or off state) the plurality of injection valves 30 should be in at this time and how long it should be maintained in this operation state (i.e., obtains the first period) based on the intake pressure of the anode 11 and the preset pressure of the anode 11, the second controller 92 obtains the fuel concentration at the intake end of the anode 11 at this time based on the opening degree and the opening and closing period of the exhaust valve 53, to determine what operating state the plurality of injection valves 30 should be in at that time and the length of time that this operating state should be maintained (i.e. the second period is acquired), and further comprehensively determines which operation state and the maintenance period the plurality of injection valves 30 should be maintained in respectively through the first period and the second period, and correspondingly controls the injection valve 30 to switch to the corresponding working state for maintaining the corresponding working duration.

In the embodiment shown in fig. 2, the first controller 91 determines the operation state (i.e., the on state or the off state) of the plurality of injection valves 30 and the duration of the operation state (i.e., obtains the first period) according to the intake pressure of the anode 11 and the preset pressure of the anode 11, and the second controller 92 obtains the fuel concentration at the intake end of the anode 11 according to the opening degree and the opening/closing period of the exhaust valve 53 to determine the operation state and the duration of the operation state of the plurality of injection valves 30 (i.e., obtains the second period), so as to comprehensively determine the operation state and the duration of the operation state of the plurality of injection valves 30 through the first period and the second period, and correspondingly control the injection valves 30 to switch to the corresponding operation state and maintain the corresponding operation duration.

Thus, the first controller 91 and the second controller 92 can control the injection valve 30 more easily and conveniently, and the fuel supply amount to the fuel cell system 100 can be more reasonable and stable.

As shown in fig. 1 and 2, a plurality of injection valves 30 are disposed in parallel between the holding tank 20 and the ejector 94. In this way, at least one of the plurality of injection valves 30 can be controlled to be opened according to the operating state of the fuel cell system 100, so that the injection valve 30 can supply a reasonable amount of fuel to the intake end of the anode 11, further improving the operating stability of the fuel cell system 100.

As shown in fig. 2, preferably, the fuel cell system 100 further includes: proportional solenoid valve 95, proportional solenoid valve 95's one end and storage tank 20 intercommunication, proportional solenoid valve 95's the other end and the inlet end intercommunication of ejector 94, proportional solenoid valve 95 and injection valve 30 parallel arrangement. In this way, the fuel in the storage tank 20 can flow out through the proportional solenoid valve 95 and the plurality of injection valves 30, and the control of the fuel supply amount is realized by controlling the duty ratio of the proportional solenoid valve 95 and the open/close state of the injection valves 30, so that the control of the fuel supply amount is more accurate and reliable, and the working stability of the fuel cell system 100 is improved.

In some embodiments, the proportional solenoid valve 95 may be used under high load conditions by providing the proportional solenoid valve 95 such that multiple injection valves 30 may be used when the fuel cell system 100 is at low load. Thus, when the fuel cell system 100 is under a high load condition, the pressure control of the proportional solenoid valve 95 is smoother by providing the required pressure through the proportional solenoid valve 95, and the operation stability of the fuel cell system 100 can be improved.

Of course, the fuel cell system 100 of the present application is not limited thereto, and in other embodiments, the proportional solenoid valve 95 may be controlled to cooperate with the injection valve 30 to supply the fuel to the fuel cell system 100 more sufficiently by providing the proportional solenoid valve 95, so that a plurality of injection valves 30 may be used when the fuel cell system 100 is under a low load condition.

Referring to fig. 1 and 2, the fuel cell system 100 further includes: the air-cooled cell stack comprises a cooling module 60, an air module 70 and a high voltage module 80, wherein the cooling module 60 is suitable for cooling the cell stack 10, the air module 70 is communicated with the cathode 12 of the cell stack 10, and the high voltage module 80 is electrically connected with the cell stack 10 to output voltage.

In the embodiment shown in fig. 2, the fuel cell system 100 further includes: a third controller 93, the third controller 93 being adapted to control the opening degree of the proportional solenoid valve 95 according to the intake pressure of the anode 11. In this way, the opening degree of the proportional cell valve 95 is made more appropriate to further improve the accuracy of fuel supply when the injection valve 30 supplies fuel in cooperation with the proportional cell valve 95.

In the present application, the first controller 91, the second controller 92, and the third controller 93 may be PID controllers based on PID logic, or may be controllers that implement control of the injection valve 30 and the proportional solenoid valve 95 described above by using other control logic.

According to the control method of the fuel cell system 100 of the embodiment of the invention, the control method includes: s1: the first controller 91 acquires a first period from the intake pressure of the anode 11 and the set pressure of the anode 11; s2: the second controller 92 acquires a second period according to the opening degree of the exhaust valve 53; s3: the opening and closing period of each injection valve 30 is adjusted according to the first period and the second period.

According to the control method of the fuel cell system 100 of the embodiment of the invention, the periodic control of the injection valve 30 between the on state and the off state is realized through the reverse control of the first controller 91 and the second controller 92 (i.e. obtaining the intake pressure of the anode 11, the position of the exhaust valve 53, etc.), so that both the pressure of the anode 11 and the fuel excess coefficient of the anode 11 can meet the working requirement of the fuel cell system 100, and the working stability of the fuel cell system 100 is effectively improved.

It can be understood that, the first controller 91 and the second controller 92 of this embodiment can both implement closed-loop feedback, so that the injection valve 30 can be quickly adjusted to a corresponding working state, and the response speed of the injection valve 30 is improved, and meanwhile, the working state of the injection valve 30 is based on data obtained by a previous test, and then after the corresponding state is obtained by looking up a table (i.e., after the loop is opened and looking up the table), the closed-loop feedback control is performed.

Further, the control method further comprises: a1: the third controller 93 acquires a third period from the intake pressure of the anode 11 and the set pressure of the anode 11; a2: the duty cycle of the proportional solenoid valve 95 is adjusted according to the third period.

In this way, the proportional solenoid valve 95 is periodically controlled, and the duty ratio of the proportional solenoid valve 95 is appropriately adjusted to further improve the fuel supply of the fuel cell system 100 and improve the operation stability of the fuel cell system 100.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

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

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

In the description of the present invention, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, and may also include the first and second features being in contact with each other not directly but through another feature therebetween.

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

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean 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, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. 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 invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.