A solid oxide fuel cell system

Abstract

The present invention relates to a solid oxide fuel cell system, which includes a gas storage tank, an injector, a reforming chamber, and a battery module connected in sequence through pipelines; a first heat exchanger is connected to the pipeline between the gas storage tank and the injector, and the primary flow generated by the gas storage tank enters the primary flow interface of the injector after being heated through the pipeline by the first heat exchanger. The anode of the battery module is connected to the hot fluid inlet of the first heat exchanger through a pipeline, the hot fluid outlet of the first heat exchanger is connected to the inlet of the condenser through a pipeline, and the outlet of the condenser is connected to the secondary flow interface of the injector. By using part of the heat of the exhaust gas generated by the anode to increase the temperature of the primary flow before entering the injector and reduce the temperature of the secondary flow before entering the injector, the performance of the injector can be improved without changing the back pressure, enabling the injector to obtain high performance under high back pressure conditions and meeting the requirements of the carbon deposition ratio of the solid oxide fuel cell system.

Description

Technical Field

[0001] The present invention relates to the technical field of solid oxide fuel cells, and particularly to a solid oxide fuel cell system. Background Art

[0002] The statements in this part only provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] In a solid oxide fuel cell system, the exhaust gas discharged from the anode of the stack still contains a large amount of unburned gas and unused waste heat. At present, various methods such as suction pumps or ejectors are used to recover this part of the gas and waste heat.

[0004] For example, in a solid oxide fuel cell system with an ejector to meet the anode gas circulation, the gas storage tank forms the primary flow of the ejector, sucks in part of the exhaust gas generated by the anode of the solid oxide fuel cell, and after mixing, enters the reforming chamber to undergo a reforming displacement reaction, and then enters the solid oxide fuel cell to generate electric energy.

[0005] To ensure the normal operation of the reforming chamber and the fuel cell stack and prevent carbon accumulation. Generally, in a solid oxide fuel cell, the reaction in the reforming chamber can ensure that the carbon content is within a safe value, which makes the reaction pressure in the reforming chamber relatively low. Due to the objective reasons that the reforming chamber is directly connected to the outlet of the ejector and there is a pressure loss in the fuel cell stack, the relatively low reforming chamber pressure means a higher pressure ratio for the ejector (i.e., the pressure boost from the secondary flow pressure to the back pressure). And the ejector is in different working modes according to different back pressures. The high back pressure condition and the high performance condition are contradictory to each other for the ejector. Therefore, for the current method of using an ejector to recover the anode gas of a solid oxide fuel cell, it is difficult for the system requirements of back pressure and performance to be achieved for the ejector. Summary of the Invention

[0006] In order to solve the technical problems existing in the above background art, the present invention provides a solid oxide fuel cell system, which uses part of the heat of the exhaust gas generated by the anode to increase the temperature of the primary flow before entering the ejector and reduce the temperature of the secondary flow before entering the ejector, and can improve the performance of the ejector without changing the back pressure, so that the ejector can obtain high performance under the condition of high back pressure and meet the requirements of the carbon deposition ratio of the solid oxide fuel cell system.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] The first aspect of the present invention provides a solid oxide fuel cell system, including: a gas storage tank, an ejector, a reforming chamber, and a battery module connected in sequence through pipelines;

[0009] A first heat exchanger is connected to the pipeline between the gas storage tank and the ejector. The primary flow generated by the gas storage tank enters the primary flow interface of the ejector through the pipeline after being heated by the first heat exchanger. The anode of the battery module is connected to the hot fluid inlet of the first heat exchanger through a pipeline. The hot fluid outlet of the first heat exchanger is connected to the inlet of the condenser through a pipeline. The outlet of the condenser is connected to the secondary flow interface of the ejector through a pipeline.

[0010] The second aspect of the present invention provides a solid oxide fuel cell system, including: a gas storage tank, an ejector, a reforming chamber, and a battery module connected in sequence through pipelines;

[0011] A first heat exchanger is connected to the pipeline between the gas storage tank and the ejector. The primary flow generated by the gas storage tank enters the primary flow interface of the ejector through the pipeline after being heated by the first heat exchanger. The anode of the battery module is connected to the hot fluid inlet of the first heat exchanger through a pipeline. The hot fluid outlet of the first heat exchanger is connected to the hot fluid inlet of the second heat exchanger through a pipeline. The hot fluid outlet of the second heat exchanger is connected to the inlet of the condenser. The outlet of the condenser is connected to the secondary flow interface of the ejector through a pipeline; The second heat exchanger is connected to the pipeline between the ejector and the reforming chamber. The mixed fluid at the outlet of the ejector enters the reforming chamber through the pipeline after being heated by the second heat exchanger.

[0012] The battery module is a solid oxide fuel cell.

[0013] The outlet of the gas storage tank is connected to a pressure reducing valve, and the outlet of the pressure reducing valve is connected to the first heat exchanger through a pipeline.

[0014] The outlet pipeline of the gas storage tank is connected to a first temperature sensor, and the outlet pipeline of the reforming chamber is connected to a tenth temperature sensor.

[0015] The pipeline of the primary flow interface of the ejector is connected to a second temperature sensor.

[0016] The outlet pipeline of the anode of the solid oxide fuel cell is connected to a third temperature sensor.

[0017] The pipeline of the hot fluid inlet of the first heat exchanger is connected to a fourth temperature sensor, and the pipeline of the hot fluid outlet of the first heat exchanger is connected to a fifth temperature sensor.

[0018] The pipeline of the hot fluid outlet of the second heat exchanger is connected to a sixth temperature sensor, and a ninth temperature sensor is connected to the pipeline between the outlet of the second heat exchanger and the reforming chamber.

[0019] The outlet pipeline of the ejector is connected to a seventh temperature sensor, and the outlet pipeline of the condenser is connected to an eighth temperature sensor.

[0020] Compared with the prior art, the above one or more technical solutions have the following beneficial effects:

[0021] 1. A heat exchanger and a condenser are installed in front of the fluid entering the ejector in the system, which can increase the temperature of the primary flow before entering the ejector and decrease the temperature of the secondary flow before entering the ejector, can improve the performance of the ejector without changing the back pressure, enable the ejector to obtain high performance under high back pressure conditions, and meet the requirements of the carbon deposition ratio of the solid oxide fuel cell system.

[0022] 2. A heat exchanger and a matching condenser are respectively installed in front of the fluid entering the ejector and the reforming chamber in the system, which can further increase the temperature of the primary flow before entering the ejector and decrease the temperature of the secondary flow before entering the ejector, can improve the performance of the ejector without changing the back pressure, enable the ejector to obtain high performance under high back pressure conditions, and meet the requirements of the carbon deposition ratio of the solid oxide fuel cell system.

[0023] 3. The temperature at the inlet of the reforming chamber is increased to reduce the temperature fluctuation in the reforming chamber, making the reaction in the reforming chamber more sufficient to increase the hydrogen content in the output gas.

[0024] 4. Through the heat exchanger and the cooperating temperature sensor, the output power of the battery system can be indirectly adjusted by controlling the temperature of the primary flow or the secondary flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The schematic diagrams in the specification forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0026] Figure 1 is a schematic structural diagram of a solid oxide fuel cell system in the prior art of the present invention;

[0027] Figure 2 is a schematic diagram of the principle of the corresponding relationship between the back pressure and the entrainment ratio of the ejector in the solid oxide fuel cell system provided by one or more embodiments of the present invention;

[0028] Figure 3 is a schematic structural diagram of a solid oxide fuel cell system provided by Embodiment 1 of the present invention;

[0029] Figure 4 are respectively schematic structural diagrams of the ejector in the solid oxide fuel cell system provided by one or more embodiments of the present invention;

[0030] Figure 5 is a schematic structural diagram of a solid oxide fuel cell system provided by Embodiment 2 of the present invention;

[0031] In the figure: 1. Gas storage tank, 2. Ejector, 3. Reforming chamber, 4. Solid oxide fuel cell, 51. First heat exchanger, 52. Second heat exchanger, 6. Condenser. Detailed implementation manners

[0032] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0034] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] The steam to carbon ratio (STCR) is used to measure the chemical composition of the anode gas supplied to the fuel cell in the anode gas circulation system of a solid oxide fuel cell and must be maintained above 1.80. If it is too low, carbon deposition will occur in the reforming chamber and inside the battery, affecting the performance and lifespan of the battery. Its calculation is as follows:

[0036]

[0037] Wherein, and n CO respectively refer to the molar flow rates of water vapor, methane, and carbon monoxide in the gas entering the reforming chamber.

[0038] The reforming displacement reaction refers to the reaction of water and heat contained in the anode exhaust gas of a solid oxide fuel cell with the fuel (generally methane) entering the cell to obtain a hydrogen-rich gas, specifically:

[0039] Reforming reaction:

[0040] Displacement reaction:

[0041] As described in the background art, the system structure for recovering the anode exhaust gas of a solid oxide fuel cell using an ejector in the prior art is as Figure 1As shown in the figure, it consists of a fuel gas storage tank (the solid oxide is generally methane), an injector, a reforming chamber, and a fuel cell stack. Among them, the fuel gas storage tank, the injector, the fuel cell stack, and several ventilation pipes form an anode exhaust gas recycling system, which cyclically reuses the unburned hydrogen and the waste heat contained in the exhaust gas discharged from the anode of the fuel cell stack. When the primary flow formed by the high-pressure gas storage tank passes through the nozzle of the injector, the static pressure energy and thermal energy of the air flow are converted into kinetic energy, forming a low pressure at the nozzle outlet to suck the entrained fluid, and due to the turbulent diffusion of the jet boundary layer, it mixes with the surrounding entrained fluid for energy exchange. Therefore, when the anode exhaust gas is discharged from the fuel cell stack, part of the gas is cycled through the pipeline and entrained into the injector, thus forming a mixed fluid with a medium pressure. After the working fluid and the entrained fluid enter the mixing chamber, the velocities are equalized, usually accompanied by an increase in pressure. Subsequently, the fluid enters the diffuser chamber, the velocity continuously slows down, and the kinetic energy is continuously converted into static pressure energy. Then the mixed gas flows out of the injector and enters the reforming chamber to undergo a reforming and displacement reaction. After the reforming and displacement reaction, most of the methane is converted into hydrogen, and the hydrogen-rich gas after the conversion finally flows into the fuel cell stack to undergo an electrochemical reaction to generate electric energy.

[0042] To ensure the normal operation of the reforming chamber and the fuel cell stack and prevent carbon deposition. In general, solid oxide fuel cells ensure that the reaction in the reforming chamber can keep the carbon content within a safe value, which makes the reaction pressure in the reforming chamber generally low, and requires the injector performance to meet the requirement that the carbon deposition ratio (STCR) is not less than 1.80. However, since the reforming chamber is directly connected to the injector outlet, the lower reforming chamber pressure means a higher pressure ratio (i.e., the pressure increase from the secondary flow pressure to the back pressure) for the injector.

[0043] The back pressure has an important influence on the performance of the injector: when the back pressure of the injector is different, the injector is in three different working modes, namely the critical mode, the subcritical mode, and the reflux mode. As Figure 2 shown, when the back pressure is small, the entrainment ratio of the injector always remains constant with the increase of the back pressure, and at this time the entrainment ratio is the maximum value. When the back pressure increases to the critical point, continuing to increase the back pressure, the entrainment ratio rapidly decreases until it decreases to 0. This process is the subcritical mode. When the back pressure continues to increase, a reflux phenomenon will occur, that is, the injector loses its entrainment function, and the primary flow flows back to the secondary flow inlet side. At this time, the injector works in the reflux mode. Among them, the critical back pressure is the critical value for the mutual conversion between the critical mode and the subcritical mode, and it is the critical working point of the injector. It can be seen that the high back pressure condition and the high performance condition are contradictory to the injector, and the back pressure and performance required by the solid oxide fuel cell system are difficult to achieve for the injector under normal circumstances.

[0044] Therefore, under high backpressure conditions, the performance of the ejector is difficult to meet the requirements of STCR, which is extremely harmful to the entire battery system.

[0045] The following embodiments provide a solid oxide fuel cell system that utilizes part of the heat of the waste gas generated by the anode to increase the temperature of the primary flow before it enters the ejector and decrease the temperature of the secondary flow before it enters the ejector. This can improve the performance of the ejector without changing the backpressure, enabling the ejector to achieve high performance under high backpressure conditions and meet the requirements of the carbon deposition ratio of the solid oxide fuel cell system.

[0046] Embodiment 1:

[0047] As Figure 3 shown, a solid oxide fuel cell system includes: a gas storage tank 1, an ejector 2, a reforming chamber 3, and a solid oxide fuel cell 4 connected in sequence through pipelines;

[0048] A first heat exchanger 51 is connected to the pipeline between the gas storage tank 1 and the ejector 2. The primary flow generated by the gas storage tank 1 enters the primary flow interface of the ejector 2 through the pipeline after being heated by the first heat exchanger 51. The anode of the solid oxide fuel cell 4 is connected to the hot fluid inlet of the first heat exchanger 51 through a pipeline. The hot fluid outlet of the first heat exchanger 51 is connected to the inlet of the condenser 6 through a pipeline, and the outlet of the condenser 6 is connected to the secondary flow interface of the ejector 2 through a pipeline.

[0049] A second heat exchanger 52 is connected to the pipeline between the ejector 2 and the reforming chamber 3. The mixed fluid at the outlet of the ejector 2 enters the reforming chamber 3 through the pipeline after being heated by the second heat exchanger 52. The hot fluid inlet of the second heat exchanger 52 is connected to the hot fluid outlet of the first heat exchanger 51 through a pipeline, and the hot fluid outlet of the second heat exchanger 52 is connected to the inlet of the condenser 6 through a pipeline.

[0050] The outlet pipeline of the gas storage tank is connected to a first temperature sensor to obtain the first temperature T p-tank .

[0051] The pipeline of the primary flow interface of the ejector is connected to a second temperature sensor to obtain the second temperature T p .

[0052] The anode outlet pipeline of the solid oxide fuel cell is connected to a third temperature sensor to obtain the third temperature T Stack .

[0053] The pipeline of the hot fluid inlet of the first heat exchanger is connected to a fourth temperature sensor to obtain the fourth temperature T s-Stack .

[0054] The pipeline of the hot fluid outlet of the first heat exchanger is connected to a fifth temperature sensor to obtain the fifth temperature T s-HE1。

[0055] The hot fluid outlet pipe of the second heat exchanger is connected to a sixth temperature sensor to obtain the sixth temperature T s-HE2 。

[0056] The outlet pipe of the ejector is connected to a seventh temperature sensor to obtain the seventh temperature T o-Ejector 。

[0057] The outlet pipe of the condenser is connected to an eighth temperature sensor to obtain the eighth temperature T s 。

[0058] A ninth temperature sensor is connected to the pipe between the outlet of the second heat exchanger and the reforming chamber to obtain the ninth temperature T o-HE2 。

[0059] The outlet pipe of the reforming chamber is connected to a tenth temperature sensor to obtain the tenth temperature T R 。

[0060] As Figure 3 shown, after adding a double heat exchanger and a single condenser, the gas circulation in the system is still a single loop: the anode exhaust gas flows out from the anode of the fuel cell stack; it enters the first heat exchanger through a pipe for preliminary heat exchange with the primary flow. At this time, the temperature of the primary flow rises from T p-tank to T p and the primary flow enters the ejector at this temperature. The temperature of the secondary flow drops from T s-Stack to T s-HE1 ; then, to make full use of the waste heat contained in the secondary flow, the secondary flow exchanges heat with the outlet again, and its temperature drops from T s-HE1 to T s-HE2 , and the temperature of the outlet fluid rises from T o-Ejector to T o-HE2 , and then enters the reforming chamber to participate in the reaction; to further reduce the temperature of the secondary flow and utilize the waste heat, the secondary flow flowing out from the second heat exchanger will pass through the condenser for condensation again. The waste heat obtained by condensation can be used for refrigeration and other purposes, and the temperature of the secondary flow drops to T s and is sucked into the ejector to be mixed with the primary flow to generate the outlet fluid. Thus, a complete anode exhaust gas circulation process with a double heat exchanger and a single condenser is formed. During the circulation process, the heat contained in the secondary flow is fully utilized through the first heat exchanger, the second heat exchanger, and the condenser. The water, which occupies the main component of the secondary flow, increases the reaction rate due to the improvement of the ejector performance, and at the same time enables the STCR of the reforming chamber and the fuel cell stack to meet the requirements. It should be noted that according to the theory, the flow rate of the primary flow of the ejector, which is the main energy source of the fuel cell, changes with temperature. Therefore, during actual operation, the output power of the fuel cell stack can be indirectly adjusted by appropriately adjusting the two heat exchangers.

[0061] During the normal operation of the battery system, the anode exhaust gas containing water vapor, unburned gas, etc. generated by the battery stack is discharged. At this time, part of the exhaust gas is repeatedly absorbed and utilized by the ejector in the exhaust gas recycling system in the low-pressure area generated by the high-speed primary flow. Since the ejector, compared with the suction pump, does not directly consume mechanical work or electrical energy to increase parameters such as fluid pressure and temperature, and has a simple structure, low cost, and no moving parts, it is applied to the anode exhaust gas recycling system. The structural schematic diagram of the ejector is as shown in Figure 4 shown, where NXP refers to the nozzle exit position.

[0062] Before the fluid enters the ejector and the reforming chamber in the above system, a heat exchanger or a condenser is installed. The purpose of installing the heat exchanger or the condenser is to increase the temperature of the primary flow before entering the ejector and reduce the temperature of the secondary flow before entering the ejector, so as to improve the performance of the ejector; at the same time, increase the temperature at the inlet of the reforming chamber to reduce the temperature fluctuation in the reforming chamber, make the reaction in the reforming chamber more sufficient, and improve the hydrogen content in the output gas.

[0063] In a solid oxide fuel cell system, due to the requirements of reforming, the ejector has relatively high performance requirements under high back pressure to prevent carbon deposition. In the traditional ejector anode exhaust gas recycling system, the temperature difference between the primary flow and the secondary flow of the ejector is too large, and a relatively high pressure ratio is required, resulting in poor performance; at the same time, the fluid at the outlet of the ejector directly enters the reforming chamber, which is likely to cause temperature fluctuations in the reforming chamber, consume additional energy, and is not conducive to the reaction in the reforming chamber. The method of installing a heat exchanger or a condenser given in this embodiment can effectively alleviate these problems, and through the heat exchanger and the cooperating temperature sensor, the output power of the battery system can be indirectly adjusted by controlling the temperature of the primary flow or the secondary flow.

[0064] The analysis method is as follows:

[0065] According to the "critical circle" theoretical model of the ejector, the mass flow rate m of the primary flow of the ejector p is:

[0066]

[0067] where, P p is the primary flow pressure, A t is the nozzle throat area, T p is the primary flow temperature, κ is the specific heat ratio, R g is the gas constant, and Ψ p is a parameter related to the isentropic flow efficiency.

[0068] The mass flow rate m of the secondary flow of the ejector s is:

[0069]

[0070] Among them, P sm is the pressure of the secondary flow at the m-m cross-section, V Figure 4 is the velocity of the primary flow at the m-m cross-section, T pm is the temperature of the secondary flow at m-m, R sm is the radius of the ejector cross-section at m-m, R m is the radius of the region occupied by the primary flow at m-m, and n is a parameter related to R pm and R pm and R m related.

[0071] The performance of the ejector is mainly represented by the entrainment ratio ω, that is:

[0072]

[0073] And the relationship between the entrainment ratio and STCR is:

[0074]

[0075] Among them, M o is the molar mass, n is the molar flow rate, and i is the component of the fluid.

[0076] Based on this, it can be judged that the mass of the primary flow and the secondary flow is highly correlated with their respective temperatures, that is, the performance of the ejector is highly correlated with its inlet temperature, and STCR increases with the increase of the entrainment ratio. Therefore, on this basis, this embodiment proposes to install a heat exchanger in the anode gas circulation loop to make full use of the waste heat in the anode exhaust gas and improve the performance of the ejector to meet the requirements of STCR. And the primary flow of the ejector is the main energy source of the fuel cell stack, while components such as water in the secondary flow are the main sources of the reactions in the reforming chamber. Therefore, changing the performance of the ejector through the heat exchanger can also indirectly adjust the power output of the fuel cell stack.

[0077] For the heat exchanger, without considering factors such as heat loss, the heat exchange amount of the two fluids participating in heat exchange is equal, and the temperature of the original high-temperature fluid at the outlet of the heat exchanger is greater than or equal to the original low-temperature fluid and other conditions. That is, at the outlet of the heat exchanger:

[0078] T H ≥T L

[0079] Q H =Q L

[0080] H refers to the original high-temperature fluid, and L refers to the original low-temperature fluid. Q refers to the heat exchange amount, that is:

[0081] Q = m·q

[0082] Wherein, m is the mass flow rate, and q is the heat transfer per unit mass.

[0083] According to the above heat exchanger conditions, it can be judged that within a certain range, the high-temperature exhaust gas flowing out of the anode can heat the lower primary flow temperature through the heat exchanger, thereby improving the performance of the ejector and meeting the requirements of the reforming chamber and the STCR of the fuel cell stack.

[0084] For a solid oxide fuel cell stack, its current density i is:

[0085]

[0086] Wherein, is the molar flow rate of hydrogen consumed by the fuel cell stack, F is the Faraday constant, and A is the total area of the fuel cell stack.

[0087] The fuel cell stack voltage U is:

[0088] U = U oc - U loss

[0089] Wherein, U oc is the ideal voltage of the fuel cell stack, and U loss is the voltage loss due to activation, polarization, and concentration resistances, etc.

[0090] The power of the fuel cell stack is:

[0091] P = U·I

[0092] According to the above analysis method, by synthesizing each formula, the required primary flow mass flow rate and temperature can be calculated from the power of the fuel cell stack, and the heat exchanger can be adjusted accordingly to change T p (the temperature at the primary flow interface pipe of the ejector, which can be achieved by changing the anode exhaust gas flow rate entering / leaving the first heat exchanger, or by changing the flow rate of the primary flow entering the ejector), T s (the temperature of the condenser outlet pipe, which can be achieved by changing the cold fluid flow rate entering / leaving the condenser, or by changing the flow rate of the secondary flow entering the ejector), etc.

[0093] Embodiment 2:

[0094] As Figure 5 shown, a solid oxide fuel cell system includes: a gas storage tank, an ejector, a reforming chamber, and a solid oxide fuel cell connected in sequence through pipelines;

[0095] A first heat exchanger is connected to the pipeline between the gas storage tank and the injector. The primary flow generated by the gas storage tank enters the primary flow interface of the injector through the pipeline after being heated by the first heat exchanger. The anode of the solid oxide fuel cell is connected to the hot fluid inlet of the first heat exchanger through a pipeline. The hot fluid outlet of the first heat exchanger is connected to the inlet of the condenser through a pipeline. The outlet of the condenser is connected to the secondary flow interface of the injector.

[0096] In this embodiment, the second heat exchanger is cancelled on the basis of Embodiment 1, and only one heat exchanger and the condenser cooperate with each other to improve the performance of the injector. Correspondingly, the fifth temperature sensor connected to the hot fluid outlet pipeline of the first heat exchanger acquires the fifth temperature T s-HE (corresponding to T s-HE1 in Embodiment 1).

[0097] As Figure 5 shown, after installing a single heat exchanger and a single condenser, the gas cycle in the system is also a single loop: the anode exhaust gas flows out from the anode of the fuel cell stack; it enters the heat exchanger through the pipeline and exchanges heat with the primary flow initially. At this time, the temperature of the primary flow rises from T p-tank to T p and the primary flow enters the injector at this temperature. The temperature of the secondary flow drops from T s-Stack to T s-HE ; then the secondary flow no longer exchanges heat but directly enters the condenser for condensation, releasing the remaining waste heat available for refrigeration and other purposes, and its temperature drops to T s and enters the injector to be entrained at this temperature; the gas flowing out of the outlet will directly enter the reforming chamber to participate in the reaction. This is a complete cycle process of the anode exhaust gas with a single heat exchanger and a single condenser installed. During the cycle process, compared with the double heat exchangers, more waste heat of the secondary flow can be taken away by the condenser for other purposes under the single heat exchanger, and similarly, the performance of the injector is also improved. However, compared with the double heat exchangers, the outlet fluid directly flows into the reforming chamber under the single heat exchanger, which will cause temperature fluctuations in the reforming chamber and is not conducive to the reforming displacement reaction. Similar to the double heat exchangers, the power of the fuel cell stack can also be adjusted by adjusting the heat exchanger during actual operation under the single heat exchanger.

[0098] A heat exchanger or a condenser is installed at the fluid inlet of the injector in the above system. The purpose of installing the heat exchanger or the condenser is to increase the temperature of the primary flow before entering the injector and reduce the temperature of the secondary flow before entering the injector, so as to improve the performance of the injector; or increase the temperature at the inlet of the reforming chamber to reduce the temperature fluctuations in the reforming chamber, make the reaction in the reforming chamber more sufficient, and increase the hydrogen content in the output gas. The temperature of the fluid at the injector inlet can be adjusted through the heat exchanger, and various parameters such as the output power of the fuel cell stack can be adjusted.

[0099] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A solid oxide fuel cell system, characterized in that: Comprising: A gas storage tank, an injector, a reforming chamber, and a battery module connected in sequence through pipelines; A first heat exchanger is connected to the pipeline between the gas storage tank and the injector. The primary flow generated by the gas storage tank enters the primary flow interface of the injector after being heated by the pipeline through the first heat exchanger. The anode of the battery module is connected to the hot fluid inlet of the first heat exchanger through a pipeline. The hot fluid outlet of the first heat exchanger is connected to the inlet of the condenser through a pipeline. The outlet of the condenser is connected to the secondary flow interface of the injector through a pipeline.

2. A solid oxide fuel cell system, characterized in that: Comprising: A gas storage tank, an injector, a reforming chamber, and a battery module connected in sequence through pipelines; A first heat exchanger is connected to the pipeline between the gas storage tank and the injector. The primary flow generated by the gas storage tank enters the primary flow interface of the injector after being heated by the pipeline through the first heat exchanger. The anode of the battery module is connected to the hot fluid inlet of the first heat exchanger through a pipeline. The hot fluid outlet of the first heat exchanger is connected to the hot fluid inlet of the second heat exchanger through a pipeline. The hot fluid outlet of the second heat exchanger is connected to the inlet of the condenser. The outlet of the condenser is connected to the secondary flow interface of the injector through a pipeline; The second heat exchanger is connected to the pipeline between the injector and the reforming chamber. The mixed fluid at the outlet of the injector enters the reforming chamber after being heated by the pipeline through the second heat exchanger.

3. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The battery module is a solid oxide fuel cell.

4. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The outlet of the gas storage tank is connected to a pressure reducing valve, and the outlet of the pressure reducing valve is connected to the first heat exchanger through a pipeline.

5. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The outlet pipeline of the gas storage tank is connected to a first temperature sensor, and the outlet pipeline of the reforming chamber is connected to a tenth temperature sensor.

6. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The pipeline of the primary flow interface of the injector is connected to a second temperature sensor.

7. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The anode outlet pipeline of the solid oxide fuel cell is connected to a third temperature sensor.

8. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The pipeline of the hot fluid inlet of the first heat exchanger is connected to a fourth temperature sensor, and the pipeline of the hot fluid outlet of the first heat exchanger is connected to a fifth temperature sensor.

9. The solid oxide fuel cell system according to claim 2, characterized in that: The pipeline of the hot fluid outlet of the second heat exchanger is connected to a sixth temperature sensor, and a ninth temperature sensor is connected to the pipeline between the outlet of the second heat exchanger and the reforming chamber.

10. A solid oxide fuel cell system according to claim 1 or 2, characterized in that: The pipeline at the outlet of the injector is connected to a seventh temperature sensor, and the pipeline at the outlet of the condenser is connected to an eighth temperature sensor.

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