Combined cooling heating and power generation system based on fuel cell

Abstract

The utility model discloses a combined cooling heating and power generation system based on a fuel cell. The combined cooling heating and power generation system comprises an air filter, an air compression / expansion module, an intercooler, a dry and wet air control module and a fuel cell stack, the air compression / expansion module comprises an air compression unit, a water separator and an air expansion unit, and an inlet of the air compression unit is connected with the air filter to receive filtered air; an outlet of the air compression unit is connected with an inlet of the intercooler; the dry and wet air control module comprises a dry side inlet, a dry side outlet, a wet side inlet and a wet side outlet, the dry side inlet is connected with the outlet of the intercooler, the side outlet is connected with the air inlet of the fuel cell stack, the wet side inlet is connected with the air outlet of the fuel cell stack, and the wet side outlet is connected with the inlet of the separator. The air compression / expansion module with the expansion machine is selected for tail exhaust energy recovery, a water-gas separation device is integrated at an inlet of the expansion machine, auxiliary power consumption is reduced, and the power generation efficiency of the system is improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of combined cooling, heating and power (CCHP) equipment, and particularly relates to a CHP power generation system based on fuel cells. Background Technology

[0002] Combined cooling, heating, and power (CCHP) is an important way to achieve energy efficiency. Traditional methods typically utilize thermodynamic cycles or devices such as organic Rankine cycles, absorption refrigeration / heat pumps, and heat exchangers to further utilize waste heat from power plants or industries, achieving CCHP goals and improving the overall utilization efficiency of fossil fuels. This technological path belongs to waste heat-driven CCHP technology. Waste heat-driven CCHP systems require waste heat resources of a certain grade, and the system cycle is relatively complex. If there are no waste heat resources, electric heating, electric heat pumps, and electric refrigeration technologies can be used to achieve heating and cooling goals. However, this technological path consumes a lot of electricity. If the electricity comes from fossil fuels, it will increase pollutant and greenhouse gas emissions; if the electricity comes from renewable energy sources, large-capacity energy storage equipment is required.

[0003] A PEMFC fuel cell power generation system is an electrochemical reaction power generation device that requires external fuel supply, oxidant treatment equipment, and cooling auxiliary equipment during operation. During system operation, both the main and auxiliary equipment generate a significant amount of heat. Therefore, improving system efficiency and recovering the heat generated by the power generation system are the current technological starting points for PEMFC fuel cell power generation systems. Currently, most PEMFC fuel cell power generation systems directly release heat into the atmosphere, while some projects recover the heat generated by the main equipment for residential heating, etc. With the large-scale application of fuel cell power generation systems in the future, the heat generated by auxiliary equipment will be substantial. Therefore, during product development, the heat generated by both the main and auxiliary equipment will be recovered and reused to improve the overall system efficiency. Utility Model Content

[0004] This application aims to at least partially address one of the technical problems in the related art.

[0005] According to one aspect of this utility model, a combined cooling, heating, and power (CCHP) power generation system based on a fuel cell is provided. The CCHP power generation system includes: an air filter, an air compression / expansion module, an intercooler, a dry / wet air control module, and a fuel cell stack. The air compression / expansion module includes an air compression unit, a water separator, and an air expansion unit. The inlet of the air compression unit is connected to the air filter to receive filtered air, and the outlet of the air compression unit is connected to the inlet of the intercooler. The dry / wet air control module includes a dry-side inlet, a dry-side outlet, a wet-side inlet, and a wet-side outlet. The dry-side inlet is connected to the outlet of the intercooler, the dry-side outlet is connected to the air inlet of the fuel cell stack, the wet-side inlet is connected to the air outlet of the fuel cell stack, and the wet-side outlet is connected to the inlet of the water separator.

[0006] Preferably, the air outlet of the water separator is connected to the inlet of the air expansion unit, and the outlet of the air expansion unit is connected to the first outlet of the combined cooling, heating and power generation system.

[0007] Preferably, the air back pressure valve is located between the outlet of the air expansion unit and the first outlet of the combined cooling, heating and power (CCHP) power generation system, the liquid water outlet of the water separator is connected to the first outlet of the CCHP power generation system, and the drain valve is located between the liquid water outlet of the water separator and the first outlet of the CCHP power generation system.

[0008] Preferably, the dry and humid air control module includes a first air intake branch and a second air intake branch. The dry-side inlet of the dry and humid air control module is connected to the first end of the first air intake branch and the first end of the second air intake branch, respectively. The dry-side outlet of the dry and humid air control module is connected to the second end of the first air intake branch and the second end of the second air intake branch, respectively. A dry air humidity valve is provided in the first air intake branch, and a humidifier is provided in the second air intake branch. The dry and humid air control module also includes a first air outlet branch and a second air outlet branch. The wet-side inlet of the dry and humid air control module is connected to the first end of the first air outlet branch and the first end of the second air outlet branch, respectively. The wet-side outlet of the dry and humid air control module is connected to the second end of the first air outlet branch and the second end of the second air outlet branch, respectively. A wet air humidity valve is provided in the first air outlet branch, and the humidifier is provided in the second air intake branch.

[0009] Preferably, the combined cooling, heating, and power (CCHP) power generation system further includes a hydrogen supply and circulation module. The hydrogen supply and circulation module includes a hydrogen supply inlet, a hydrogen supply outlet, a hydrogen recovery inlet, and a hydrogen recovery outlet. The hydrogen supply outlet is connected to the hydrogen inlet of the fuel cell stack, the hydrogen recovery inlet is connected to the hydrogen outlet of the fuel cell stack, and the hydrogen recovery outlet is connected to the second outlet (2) of the CCHP power generation system. The hydrogen supply and circulation module includes a first hydrogen supply branch and a second hydrogen supply branch. The hydrogen supply inlet of the hydrogen supply and circulation module is respectively connected to the first end of the first hydrogen supply branch and the first end of the second hydrogen supply branch. The hydrogen supply outlet of the hydrogen supply and circulation module is respectively connected to the second end of the first hydrogen supply branch and the second end of the second hydrogen supply branch. The first hydrogen supply branch is provided with a first ejector and a first proportional valve. The inlet of the first proportional valve is connected to the hydrogen supply inlet, the outlet of the first proportional valve is connected to the inlet of the first ejector, and the outlet of the first ejector is connected to the hydrogen supply outlet. The second inlet branch is provided with a second ejector and a second proportional valve. The inlet of the second proportional valve is connected to the hydrogen supply inlet, the outlet of the second proportional valve is connected to the inlet of the second ejector, and the outlet of the second ejector is connected to the hydrogen supply outlet.

[0010] Preferably, the hydrogen supply and circulation module includes a hydrogen circulation branch, in which a water-gas separator is provided. The inlet of the water-gas separator is connected to the hydrogen recovery inlet, the liquid water outlet of the water-gas separator is connected to the outlet of the combined cooling, heating and power generation system, and the gas outlet of the water-gas separator is connected to another inlet of the first ejector and another inlet of the second ejector.

[0011] Preferably, the hydrogen supply and circulation module further includes a sensor disposed at the hydrogen supply outlet. The sensor senses the operating status of the fuel cell stack, and the hydrogen supply and circulation module controls the operating status of the first hydrogen supply branch and the second hydrogen supply branch based on the operating status of the fuel cell stack.

[0012] Preferably, the hydrogen supply and circulation module further includes a hydrogen pressure relief valve, the inlet of which is connected to the hydrogen supply outlet, and the outlet of which is connected to the discharge outlet of the combined cooling, heating and power generation system.

[0013] Preferably, the combined cooling, heating, and power (CCHP) system includes multiple fuel cell stacks. The air compression / expansion module, the intercooler, the dry and humid air control module, the hydrogen supply and circulation module, and the fuel cell stacks are arranged in a CCHP system container. The fuel cell stacks constitute the main equipment of the CCHP system, while the air compression / expansion module, the intercooler, the dry and humid air control module, and the hydrogen supply and circulation module constitute auxiliary equipment. The CCHP system includes multiple CCHP system containers connected in parallel. For each fuel cell stack... The fuel cell stack is equipped with a main heat exchanger and a main radiator. The first inlet of the main heat exchanger is connected to the coolant outlet of the fuel cell stack, and the first outlet of the main heat exchanger is connected to the coolant inlet of the fuel cell stack. The main radiator is coupled in parallel with the main heat exchanger. A first coolant flow valve and a first cooling water pump are installed in the connection channel between the first inlet of the main heat exchanger and the coolant outlet of the fuel cell stack, and in the connection channel between the inlet of the main radiator and the coolant outlet of the fuel cell stack. The first valve of the first coolant flow valve is connected to the first inlet of the main heat exchanger. The second valve is connected to the inlet of the main radiator. Based on the operating status of the first coolant flow valve and the first cooling water pump, one of the following operating modes is implemented: First operating mode: In the first operating mode, the first and second valves of the first coolant flow valve are simultaneously open, the first cooling water pump operates, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, and the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack; the main heat exchanger and the main radiator operate simultaneously. Second operating mode: In the second operating mode, the first coolant flow valve... In the first operating mode, the first valve of the coolant flow valve is open, the second valve of the first coolant flow valve is closed, the first cooling water pump is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger is running, and the main radiator is not running; in the third operating mode, the first valve of the first coolant flow valve is closed, the second valve of the first coolant flow valve is open, the first cooling water pump is running, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger is not running, and the main radiator is running.

[0014] Preferably, the main heat exchanger includes a plate heat exchanger, which is provided with a combined cooling, heating and power (CCHP) interface. The CCHP interface is connected to the user equipment to provide the heat energy generated by the CHP power generation system during operation to the user equipment. The main radiator includes a cooling fan.

[0015] Preferably, each fuel cell stack is provided with an auxiliary heat exchanger and an auxiliary radiator. The first inlet of the auxiliary heat exchanger is connected to the second outlet of the corresponding main heat exchanger, and the first outlet of the auxiliary heat exchanger is connected to the second inlet of the corresponding main heat exchanger. The auxiliary radiator is coupled in parallel with the auxiliary heat exchanger. A second coolant flow valve is provided in the connection channel between the first inlet of the auxiliary heat exchanger and the second outlet of the corresponding main heat exchanger. A third coolant flow valve and a second cooling water pump are provided in the connection channels between the auxiliary heat exchanger and the auxiliary equipment, and in the connection channels between the auxiliary radiator and the auxiliary equipment. The third coolant flow... The first valve of the first coolant flow valve is connected to the second inlet of the auxiliary heat exchanger, and the second valve of the first coolant flow valve is connected to the inlet of the auxiliary radiator. Based on the operating states of the first coolant flow valve, the first cooling water pump, the second coolant flow valve, the third coolant flow valve, and the second cooling water pump, one of the following operating modes is achieved: The first and second valves of the first coolant flow valve are simultaneously open, the first cooling water pump is running, the valve of the second coolant flow valve is open, the first and second valves of the third coolant flow valve are simultaneously open, the second cooling water pump is running, and the first inlet of the main heat exchanger receives water from the auxiliary radiator. The coolant at the coolant outlet of the fuel cell stack is received by the inlet of the main radiator. The first inlet of the auxiliary heat exchanger receives coolant from the second outlet of the corresponding main heat exchanger. The second inlet of the auxiliary heat exchanger receives coolant from the auxiliary equipment. The inlet of the auxiliary radiator receives coolant from the auxiliary equipment. The main heat exchanger, the auxiliary heat exchanger, the main radiator, and the auxiliary radiator operate simultaneously. In the fifth operating mode, the first valve and the second valve of the first coolant flow valve are simultaneously opened, and the first cooling water pump operates. The second coolant flow valve is open, the first valve of the third coolant flow valve is open, the second valve of the third coolant flow valve is closed, the second cooling water pump is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the first inlet of the auxiliary heat exchanger receives coolant from the corresponding second outlet of the main heat exchanger, the second inlet of the auxiliary heat exchanger receives coolant from the auxiliary equipment, the main heat exchanger is running, the auxiliary heat exchanger is running, the main radiator is running, and the auxiliary radiator is not running.In the sixth operating mode, the first and second valves of the first coolant flow valve are simultaneously open, the first cooling water pump operates, the valve of the second coolant flow valve is open, the first and second valves of the third coolant flow valve are closed, the second cooling water pump does not operate, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, and the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack. The main heat exchanger operates, the auxiliary heat exchanger does not operate, the main radiator operates, and the auxiliary radiator does not operate. (Seventh operating mode) In the seventh operating mode, the first valve of the first coolant flow valve is closed, the second valve of the first coolant flow valve is open, the first cooling water pump is running, the valve of the second coolant flow valve is closed, the first valve of the third coolant flow valve is closed, the second valve of the third coolant flow valve is open, the second cooling water pump is running, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the inlet of the auxiliary radiator receives coolant from the auxiliary equipment, the main heat exchanger is not running, the auxiliary heat exchanger is not running, the main radiator is running, and the auxiliary radiator is running.

[0016] This invention provides a stationary, efficient, and scalable PEMFC fuel cell combined cooling, heating, and power system, including a fuel processing module, an air processing module, a cooling and heat dissipation module, and a power output module. This system achieves the following technical effects:

[0017] First, an air compression / expansion module with an expander is selected for exhaust energy recovery, and a water-air separation device is integrated at the inlet of the expander to reduce auxiliary power consumption and improve the power generation efficiency of the system.

[0018] Secondly, to control the air humidity of the fuel cell stack, a parallel ejector is used for hydrogen circulation, which reduces system power loss and improves system output efficiency.

[0019] Third, a design solution is proposed to recover the heat generated by the main / auxiliary components of the fuel cell.

[0020] Fourth, the integrated independent cooling fan supplements the heat dissipation of system components, making the power generation container system easier to expand.

[0021] Fifth, the power generation system reserves an external cogeneration interface for the plate heat exchanger and provides a comprehensive design solution. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0023] Figure 1 This is a schematic block diagram illustrating a fuel cell-based combined cooling, heating and power generation system according to an embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram illustrating an air compression / expansion module according to an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram showing a hydrogen supply and circulation module according to an embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram illustrating a dry and humid air control module according to an embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram showing a combined power supply structure according to an embodiment of the present invention.

[0028] Figure 6 This is a graph showing the power generation efficiency of a system according to an embodiment of the present invention.

[0029] Figure 7 This is a graph showing the overall system efficiency according to an embodiment of the present invention.

[0030] Figure label:

[0031] Hydrogen import: 1

[0032] Hydrogen exhaust ports: 2

[0033] Air inlet: 3

[0034] Air outlets: 4

[0035] AC power output: 5

[0036] Heat exchange outlet: 6

[0037] Heat exchange inlet: 7; Air filter: 102

[0038] Air compression / expansion module: 120

[0039] Air compression unit: 206

[0040] Air expansion unit: 204

[0041] Water separator: 208

[0042] Air back pressure valve: 202

[0043] Drain valve: 210

[0044] Intercoolers: 106-A, 106-B, 106-C, 518A, 532A, 518B, 532B, 518C, 532C

[0045] Dry and humid air control modules: 108-A, 108-B, 108-C

[0046] Dry side inlet: 408

[0047] Dry side outlet: 410

[0048] Wet side inlet: 412

[0049] Wet side outlet: 414

[0050] Dry air humidity valve: 402

[0051] Humidifier: 404

[0052] Humidity valve for humid air: 406

[0053] Fuel cell stacks: 110-A, 110-B, 110-C, 506A, 508A, 506B, 508B, 506C, 508C

[0054] Hydrogen supply and circulation modules: 112-A, 112-B, 112-C

[0055] Hydrogen supply imports: 316

[0056] Hydrogen supply outlet: 314

[0057] Hydrogen recovery import: 318

[0058] Hydrogen recovery outlet: 320

[0059] First ejector: 302

[0060] Second ejector: 306

[0061] First proportional valve: 304

[0062] Second proportional valve: 308

[0063] Water-air separator: 312

[0064] Hydrogen pressure relief valve: 310

[0065] DC / AC converter: 122

[0066] DC / DC converters: 116-A, 116-B, 116-C, 520A, 530A, 520B, 530B, 520C, 530C

[0067] Heat exchangers: 118-A, 118-B, 118-C

[0068] Main heat exchangers: 502A, 502B, 502C

[0069] Main heatsinks: 504A, 504B, 504C

[0070] Auxiliary heat exchangers: 512A, 512B, 512C

[0071] Auxiliary heatsinks: 514A, 514B, 514C

[0072] Hydrogen heater module: 124

[0073] First coolant flow valve: 538A, 538B, 538C

[0074] First cooling water pump: 536A, 536B, 536C

[0075] Second coolant flow valve: 510A, 510B, 510C

[0076] Third coolant flow valve: 534A, 534B, 534C

[0077] Second cooling water pump: 516A, 516B, 516C

[0078] Cogeneration system containers: 50A, 50B, 50C Detailed Implementation

[0079] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0080] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0081] To facilitate understanding, we will now briefly introduce the components and their functions used in the fuel cell-based combined cooling, heating and power generation system according to this utility model:

[0082] PEMFC: The fuel cell discussed in this application primarily involves PEMFC, short for Proton Exchange Membrane Fuel Cell, also known as a proton exchange membrane fuel cell. It is a special type of fuel cell that uses a proton exchange membrane as the electrolyte. The working principle of a PEMFC is based on an electrochemical reaction, directly converting chemical energy (the chemical energy in the fuel) into electrical energy, while simultaneously producing water and a small amount of heat. The following are some key characteristics of PEMFC: 1. Proton Exchange Membrane: This is a special membrane that only allows protons (i.e., hydrogen ions H+) to pass through. +1. **Selective Permeability:** PEMFCs allow the passage of electrons while preventing direct electron transport. This selective permeability is crucial for the efficient operation of fuel cells. 2. **Fuel:** PEMFCs typically use hydrogen as fuel. Hydrogen reacts at the anode (one electrode of the fuel cell), breaking down into protons and electrons. Protons move to the cathode through the proton exchange membrane, while electrons flow to the cathode through an external circuit, generating an electric current. 3. **Oxidant:** Oxygen (usually extracted from air) acts as the oxidant at the cathode, combining with the protons and electrons produced by the reaction with hydrogen to generate water and usable electrical energy. 4. **Operating Temperature:** Compared to other types of fuel cells, PEMFCs operate at lower temperatures, typically between 60 and 80 degrees Celsius. This allows for faster start-up times and the use of non-precious metal catalysts. 5. **Applications:** Due to their rapid response and wide operating range, PEMFCs are widely used in automotive, portable power supplies, stationary power, and telecommunications backup power. They are considered one of the key technologies for the future of clean energy, particularly in transportation and stationary energy supply applications. Due to their high efficiency, cleanliness, and quiet operation, PEMFCs have become the focus of many research and development projects, especially in the context of seeking to reduce greenhouse gas emissions and dependence on fossil fuels. The PEMFC fuel cell systems mentioned in this application are clearly aimed at improving the operating efficiency and energy utilization of such systems, as well as addressing the heat generated during their operation.

[0083] Hydrogen pressure relief valve (HRV) is a safety device used in PEMFC (proton exchange membrane fuel cell) systems. Its main function is to automatically release excess hydrogen when the hydrogen pressure exceeds a predetermined safe range, preventing excessive pressure within the system that could damage the system or create safety hazards. In fuel cell vehicles or other devices using hydrogen as fuel, hydrogen storage tanks and supply systems are equipped with this valve to ensure that pressure exceeding safe limits does not accumulate under any circumstances. In short, the HRV protects the system from excessive hydrogen pressure by promptly releasing excess hydrogen to maintain a safe system pressure level. It is one of the key safety components in a fuel cell system. It allows for rapid response in emergencies or system malfunctions, preventing potential dangers caused by excessive hydrogen pressure.

[0084] Intercooler: Also known as an air intercooler, it is a key component in the dehumidification system of fuel cells, especially in PEMFC (proton exchange membrane fuel cell) systems. In fuel cell systems, air needs to be treated before entering the fuel cell stack to ensure appropriate humidity and temperature, thereby optimizing the efficiency and stability of the electrochemical reaction. The main function of the air intercooler is to cool and dehumidify the air entering the system. When compressed air flows out of a compressor (such as an AC: Air Compressor), its temperature is usually high, and high-temperature and high-humidity air can affect the performance of the fuel cell stack. The AIC reduces the air temperature by exchanging heat with the coolant, promoting the condensation of water vapor in the air, thereby reducing the humidity in the air. This step is crucial for the normal operation of the fuel cell because it helps control the moisture within the stack, preventing short circuits or performance degradation caused by excessive moisture, while also improving the efficiency of the entire system. In summary, the air intercooler (AIC) plays a key role in temperature control and humidity regulation in fuel cell systems, ensuring that the air entering the fuel cell stack is in optimal operating condition, thereby improving system performance and reliability.

[0085] The dry / humid air control module, also known as the air humidification module, is a crucial component of a PEMFC (Proton Exchange Membrane Fuel Cell) system. In a fuel cell, the proton exchange membrane needs to maintain a certain level of humidity to effectively conduct protons, thereby promoting the electrochemical reaction. If the membrane becomes too dry, it may lose its conductivity, leading to a decline in fuel cell performance or even damage. The primary task of the air humidification module (AH) is to adjust the humidity of the air entering the fuel cell stack, ensuring that the humidity level is suitable for the fuel cell's optimal operating conditions. This module typically includes a humidifier that increases air humidity by atomizing water or passing the air through a water bath. Furthermore, it may include humidity sensors and a control system to monitor and precisely control the humidification level in real time. In a PEMFC system, the AH module is located specifically in the air handling process, after the air has been compressed and cooled, but before entering the fuel cell stack. This ensures that the air is humidified at the appropriate pressure and temperature, thus avoiding impacting the efficiency of the electrochemical reaction or causing membrane oversaturation. In summary, the air humidification module (AH) is crucial for the effective operation of the fuel cell system. By maintaining appropriate humidity in the air, it ensures the optimal working condition of the proton exchange membrane, thereby guaranteeing the overall performance of the fuel cell.

[0086] Dry air humidity valve: In a PEMFC (proton exchange membrane fuel cell) system, the dry air humidity valve is primarily used to precisely control the humidity of the dry air (air with most moisture removed) entering the fuel cell stack. Optimal operation of the fuel cell stack requires specific humidity conditions to ensure the performance of the proton exchange membrane (PEM). The dry air humidity valve regulates the humidity of the air after the air drying and pretreatment stages to a suitable level for fuel cell stack operation. This process typically works in conjunction with other humidity management components in the fuel cell system, such as an air humidifier module (AH), to achieve precise humidity control. By regulating the dry air humidity valve, problems such as excessively low humidity leading to proton exchange membrane drying, which affects proton conductivity and fuel cell performance, can be avoided. Conversely, excessively high humidity can cause membrane oversaturation, affecting electrochemical reaction efficiency. Therefore, the dry air humidity valve is a crucial part of the humidity control strategy in a fuel cell system, playing a vital role in optimizing system operation and improving efficiency. In summary, the dry air humidity valve (DHV) in the PEMFC system is responsible for adjusting the humidity of the dry air to the ideal state, ensuring that the proton exchange membrane operates under the most suitable humidity conditions to support the efficient and stable operation of the fuel cell.

[0087] Air Control Module: Playing a central role in a PEMFC (Proton Exchange Membrane Fuel Cell) system, the air control module manages and controls airflow and humidity to ensure stable and efficient operation of the fuel cell stack. Specifically, it comprises multiple subsystems and components that work together to perform the following functions: 1. Airflow Control: The air control module ensures the fuel cell stack receives the necessary oxygen for electrochemical reactions by regulating the flow rate of incoming air. This typically involves controlling the pressure and flow rate of the air entering the system to match the power demands of the fuel cell. 2. Humidity Regulation: PEMFCs require specific humidity levels to operate effectively. The humidity control mechanism within the air control module adjusts air humidity to prevent the proton exchange membrane from becoming too dry, affecting proton conduction, or from becoming too wet, causing membrane oversaturation and performance degradation. 3. Pressure Regulation: The air control module also maintains pressure balance within the fuel cell system to optimize air distribution and reduce performance fluctuations caused by pressure changes. 4. Air Quality Monitoring: The air control module may include filtration devices to remove impurities such as dust and contaminants from the air, which can damage the fuel cell stack or reduce system efficiency. 5. Safety Functions: The air control module also bears safety responsibilities, such as cutting off the air supply when abnormal conditions are detected to prevent system damage or accidents. In summary, the air control module (ACM) is a complex system that integrates air supply, regulation, monitoring, and safety functions to ensure the fuel cell stack operates under optimal conditions while protecting the entire system from potential damage. In modern PEMFC systems, the ACM is often automated through sophisticated electronic control units to adapt to changing operating environments and power demands.

[0088] Drain valves (DWVs) are used in PEMFC (Proton Exchange Membrane Fuel Cell) systems to manage and control the discharge of excess water from the system. Water management is crucial during fuel cell operation, as water is both a reaction byproduct and a key substance for maintaining proper moisture levels in the proton exchange membrane (PEM). However, excessive water can lead to membrane supersaturation, affecting proton conductivity and even causing water buildup that obstructs gas flow, thus impacting overall system efficiency and performance. The role of drain valves (DWVs) is to periodically or as needed remove excess water from the fuel cell system to maintain moisture balance. These valves are typically used in conjunction with level sensors or other control mechanisms to monitor the system's internal moisture levels and open when necessary to drain excess water, preventing water buildup and membrane supersaturation. The design and control mechanisms of drain valves need to effectively handle moisture while ensuring the safety and efficiency of system operation. In a broader sense, the DWV is part of the water management system in a fuel cell system, helping to maintain appropriate operating conditions, ensuring a continuous and stable power generation while preventing any potential problems caused by water. By precisely controlling moisture emissions, DWV helps extend the life of fuel cells and improve their overall performance.

[0089] The air back pressure valve plays a crucial control role in PEMFC (proton exchange membrane fuel cell) systems, especially on the air outlet side. Its main function is to maintain an appropriate back pressure of the air at the fuel cell stack outlet, which is essential for ensuring uniform gas distribution and stable operation within the fuel cell stack. By adjusting the outlet air pressure, the back pressure valve controls the efficiency and stability of the electrochemical reaction. During fuel cell operation, maintaining a certain back pressure prevents excessively low air pressure, ensuring sufficient contact and reaction between hydrogen and oxygen in the stack, while avoiding airflow instability and performance degradation caused by pressure imbalances. Furthermore, appropriate back pressure helps prevent water backflow from the fuel cell stack, which is crucial for cooling and humidity management. In short, the air back pressure valve is a key safety and performance control component in the fuel cell system. By precisely controlling the air pressure on the outlet side, it ensures stable operation of the fuel cell stack and improves the overall system efficiency and reliability.

[0090] Liquid water separators (LWS) are crucial components in PEMFC (proton exchange membrane fuel cell) systems, primarily used to separate liquid water from the gas stream. Water is produced as a byproduct during the electrochemical reaction in fuel cells. This water may exist in both gaseous and liquid forms after air or hydrogen flows through the fuel cell stack. Without treatment, liquid water can accumulate in the gas flow channels, affecting gas flow and potentially leading to system performance degradation or damage. Liquid water separators (LWS) operate in several ways: 1. Gravity separation: Using gravity to separate heavier liquid water from lighter gas streams. 2. Centrifugal separation: Using rotational force to eject liquid water from the gas stream, typically achieved when the gas stream passes through a cyclone or centrifuge. 3. Filtration: Capturing liquid water droplets through porous materials or specially designed filters, allowing gas to pass through while blocking the liquid. 4. Cooling: Lowering the gas temperature, causing gaseous water to condense into liquid water, which is then separated by gravity or centrifugal force. In PEMFC systems, liquid water separators are typically located at specific points in the air or hydrogen handling process to ensure that the gas flow is dry before or after entering the fuel cell stack. This helps maintain optimal fuel cell stack operation and prevents blockages or performance issues caused by moisture buildup. By effectively separating water, liquid water separators contribute to improved system efficiency and reliability while protecting sensitive components from water erosion or freezing.

[0091] Hydrogen vapor separator (HST): In a PEMFC (proton exchange membrane fuel cell) system, it is a device specifically designed to separate and remove vapor (usually water vapor) from the hydrogen stream. During fuel cell operation, water is produced; some of this water is discharged from the system in liquid form, while some may remain in the hydrogen stream as vapor. The main functions of the hydrogen vapor separator (HST) are: 1. Vapor capture and separation: Capturing vapor carried in the hydrogen stream to prevent it from entering the fuel cell stack or other sensitive components. Excessive accumulation of this vapor can interfere with electrochemical reactions, reduce efficiency, and even damage components. 2. Maintaining hydrogen quality: By removing vapor, the HST helps maintain the dryness of the hydrogen stream, which is crucial for the stable operation of the PEMFC. Dry hydrogen reduces erosion of the proton exchange membrane, preventing membrane performance degradation. 3. Recovery and utilization: The captured vapor is usually water vapor. The HST can cool this vapor and convert it into liquid water, which can then be recovered for internal system recirculation, such as as a humidifier water source, or directly discharged to keep the system dry and efficient. In PEMFC systems, hydrogen vapor separators are typically located on the hydrogen processing line, upstream of the fuel cell stack, to ensure that the hydrogen entering the stack is dry and pure. Using hydrogen vapor separators can significantly improve the reliability and performance of the fuel cell system while reducing maintenance requirements and operating costs. In the system design, the hydrogen vapor separator works in conjunction with other humidity management components such as the air handling module and liquid water separator to maintain humidity balance within the system.

[0092] Hydrogen proportional valve: In a PEMFC (proton exchange membrane fuel cell) system, it is a precision control component used to regulate the flow and pressure of hydrogen to meet the operational requirements of the fuel cell stack. By responding to control signals, the hydrogen proportional valve can precisely adjust the hydrogen input, ensuring the smooth progress of the electrochemical reaction. The main functions of the hydrogen proportional valve include: 1. Flow control: Adjusting the hydrogen flow rate according to system requirements and control strategies to provide the required amount of hydrogen for the fuel cell stack, thereby controlling the output power. 2. Pressure regulation: In some designs, the hydrogen proportional valve can also be used to regulate the hydrogen pressure, which is crucial for preventing over-pressurization or under-pressurization of the fuel cell stack. 3. System stability: By precisely controlling the hydrogen supply, the hydrogen proportional valve helps maintain the stable operation of the fuel cell system, avoiding performance problems caused by fluctuations in hydrogen supply. 4. Safety management: In emergencies, the hydrogen proportional valve can respond quickly to reduce or cut off the hydrogen supply to mitigate potential safety risks. 5. Energy Efficiency Optimization: By adjusting hydrogen flow and pressure in real time, the hydrogen proportioning valve helps improve the system's energy efficiency, reduce hydrogen waste, and optimize the thermal management of the fuel cell stack. Within a PEMFC system, the hydrogen proportioning valve typically works in conjunction with components such as the hydrogen circulation pump, hydrogen humidifier, and hydrogen pressure sensor to maintain the quality and quantity of hydrogen supply, ensuring the efficient, stable, and safe operation of the fuel cell stack. Since hydrogen plays a crucial role in the fuel cell reaction, the performance of the hydrogen proportioning valve directly affects the energy conversion efficiency and reliability of the entire system.

[0093] Hydrogen ejector valve (HIV): A critical control component in PEMFC (proton exchange membrane fuel cell) systems, especially in designs using hydrogen recirculation or direct hydrogen supply systems. The primary function of the hydrogen ejector valve is to inject hydrogen into the hydrogen channels of the fuel cell stack at precise times to support the electrochemical reaction process. The key functions of the hydrogen ejector valve (HIV) are as follows: 1. Hydrogen injection control: When the system needs to adjust the hydrogen flow rate or supply hydrogen to the fuel cell stack, the HIV is activated to precisely control the amount of hydrogen ejected. This is typically in response to the operating status and load demands of the fuel cell stack. 2. Rapid response: The HIV needs to be able to open and close rapidly to ensure that the hydrogen supply responds instantly to dynamic changes in the system. This is crucial for maintaining stable operation of the fuel cell stack and maximizing energy output. 3. Precise metering: The HIV can precisely meter the volume of hydrogen ejected each time, which helps optimize hydrogen use, reduce waste, and maintain the hydrogen pressure within the fuel cell stack within an appropriate range, avoiding overpressure or underpressure. 4. Safety Assurance: In the event of an emergency shutdown or malfunction, HIV can quickly shut down, cutting off the hydrogen supply and reducing the risk of hydrogen leakage or potential explosion. 5. Efficiency Improvement: By precisely controlling hydrogen ejection, HIV helps improve the overall efficiency of the fuel cell system. A suitable hydrogen ejection strategy can reduce excessive hydrogen use while ensuring the reaction rate and stability of the fuel cell stack. In practical applications, HIV may work in conjunction with the control system and other valves (such as hydrogen proportioning valves) to provide the optimal hydrogen supply scheme. Through fine-grained control of hydrogen ejection, HIV helps maintain the high efficiency and safety of the PEMFC system under various operating conditions.

[0094] The present invention relates to a fuel cell-based combined cooling, heating and power generation system, which is described in detail below with reference to the accompanying drawings.

[0095] Figure 1 This is a schematic block diagram illustrating a fuel cell-based combined cooling, heating and power (CCHP) power generation system according to an embodiment of the present invention. Figure 1 As shown, the fuel cell-based cogeneration system includes: an air filter 102 for removing impurities from the air (such as dust and contaminants, which may damage the fuel cell stack or reduce system efficiency), a hydrogen inlet 1, an air inlet 3, a hydrogen exhaust port 2, a heat exchange outlet 6, a heat exchange inlet 7, an AC power outlet 5, an air outlet 4, a hydrogen heater module 124, a DC / AC converter 122, and multiple PEMFC fuel cell cogeneration system containers connected in parallel. Figure 1The diagram shows three PEMFC fuel cell cogeneration system containers arranged in parallel. However, more or fewer PEMFC fuel cell cogeneration system containers can be arranged in parallel as needed. Each PEMFC fuel cell cogeneration system container can have the same or similar construction. For example, the first PEMFC fuel cell cogeneration system container may include: an air compression / expansion module 120, which consists of units 104A and 114-A; an intercooler 106-A; a dry and wet air control module 108-A; a fuel cell stack 110-A; a hydrogen supply and circulation module 112-A; a DC / DC converter 116-A; and a heat exchanger 118-A. The second PEMFC fuel cell cogeneration system container may include: an air compression / expansion module 120', which consists of units 104B and 114-B; an intercooler 106-B; a dry and wet air control module 108-B; a fuel cell stack 110-B; a hydrogen supply and circulation module 112-B; a DC / DC converter 116-B; and a heat exchanger 118-B. The third PEMFC fuel cell cogeneration system container may include: an air compression / expansion module 120'', which consists of units 104C and 114-C; an intercooler 106-C; a dry and wet air control module 108-C; a fuel cell stack 110-C; a hydrogen supply and circulation module 112-C; a DC / DC converter 116-C; and a heat exchanger 118-C.

[0096] Since each PEMFC fuel cell cogeneration system container can have the same or similar construction, only the construction of the first PEMFC fuel cell cogeneration system container will be specifically described. In the first PEMFC fuel cell cogeneration system container, the first air inlet of unit 104A in the air compression / expansion module 120 is connected to the outlet of air filter 102 to receive filtered air, and the outlet of unit 104A in the air compression / expansion module 120 is connected to the inlet of intercooler 106-A to supply compressed air to intercooler 106-A. The dry and wet air control module 108-A includes a dry-side inlet, a dry-side outlet, a wet-side inlet, and a wet-side outlet. The dry-side inlet is connected to the outlet of intercooler 106-A, the dry-side outlet is connected to the air inlet of fuel cell stack 110-A, the wet-side inlet is connected to the air outlet of fuel cell stack 110-A, and the wet-side outlet is connected to the inlet of unit 114-A (i.e., the water separator) in the air compression / expansion module 120. The hydrogen supply and circulation module 112-A includes a hydrogen supply inlet, a hydrogen supply outlet, a hydrogen recovery inlet, and a hydrogen recovery outlet. The hydrogen supply inlet is connected to hydrogen inlet 1 via a hydrogen heater module 124. The hydrogen supply outlet is connected to the hydrogen inlet of fuel cell stack 110-A. The hydrogen recovery inlet is connected to the hydrogen outlet of fuel cell stack 110-A, and the hydrogen recovery outlet is connected to hydrogen exhaust port 2. The first inlet of heat exchanger 118-A is connected to the coolant outlet of fuel cell stack 110-A, and the first outlet of heat exchanger 118-A is connected to the coolant inlet of fuel cell stack 110-A. The second outlet of heat exchanger 118-A is connected to heat exchange outlet 6, and the second inlet of heat exchanger 118-A is connected to heat exchange inlet 7. Furthermore, the power outlet of fuel cell stack 110-A is connected to a DC / AC converter 122 via a DC / DC converter 116-A, and then the electrical energy is output to AC power outlet 5.

[0097] The following is for reference Figures 2 to 4 Describe in detail the specific structure of the components of a fuel cell-based combined cooling, heating and power (CCHP) power generation system.

[0098] Figure 2 This is a schematic diagram illustrating an air compression / expansion module according to an embodiment of the present invention. Figure 2As shown, the air compression / expansion module includes: an air back pressure valve 202, an air expansion unit 204, an air compression unit 206, a water separator 208, and a drain valve 210. The inlet of the air compression unit 206 is connected to an air filter to receive filtered air, and the outlet of the air compression unit 206 is connected to the inlet of an intercooler. The inlet of the water separator 208 is connected to the wet side outlet of the dry / wet air control module, and the air outlet of the water separator 208 is connected to the inlet of the air expansion unit 204. The liquid water outlet of the water separator 208 is connected to the air outlet 4 of the combined cooling, heating, and power (CCHP) power generation system via the drain valve 210. The first outlet of the air expansion unit 204 is connected to another inlet of the air compression unit 206, and the second outlet of the air expansion unit 204 is connected to the air outlet 4 of the CCHP power generation system via the air back pressure valve 202. According to one embodiment of the present invention, the air compression / expansion module is an air compressor integrating an expander, thereby enabling energy recovery in a power generation system. The inlet of the expander is integrated with a water vapor separator.

[0099] Figure 3 This is a schematic diagram illustrating a hydrogen supply and circulation module according to an embodiment of the present invention. Figure 3 As shown in (a), the hydrogen supply and circulation module includes: a hydrogen supply inlet 316, a hydrogen supply outlet 314, a hydrogen recovery inlet 318, and a hydrogen recovery outlet 320. The hydrogen supply outlet 316 is connected to the hydrogen inlet of the fuel cell stack, and the hydrogen recovery inlet 314 is connected to the hydrogen outlet of the fuel cell stack. The hydrogen supply and circulation module includes a first hydrogen supply branch and a second hydrogen supply branch. The hydrogen supply inlet 316 is connected to the first end of the first hydrogen supply branch and the first end of the second hydrogen supply branch, respectively. The hydrogen supply outlet 314 is connected to the second end of the first hydrogen supply branch and the second hydrogen supply branch, respectively. At the second end of the branch, the first hydrogen supply branch is equipped with a first ejector 302 and a first proportional valve 304. The inlet of the first proportional valve 304 is connected to the hydrogen supply inlet 316, the outlet of the first proportional valve 304 is connected to the inlet of the first ejector 302, and the outlet of the first ejector 302 is connected to the hydrogen supply outlet 314. The second intake branch is equipped with a second ejector 306 and a second proportional valve 308. The inlet of the second proportional valve 308 is connected to the hydrogen supply inlet 316, the outlet of the second proportional valve 308 is connected to the inlet of the second ejector 306, and the outlet of the second ejector 306 is connected to the hydrogen supply outlet 314. The hydrogen supply and circulation module also includes a hydrogen circulation branch, in which a water-gas separator 312 is installed. The inlet of the water-gas separator 312 is connected to the hydrogen recovery inlet 318, the liquid water outlet of the water-gas separator 312 is connected to the hydrogen exhaust port 2 of the combined cooling, heating and power (CCHP) power generation system, and the gas outlet of the water-gas separator 312 is connected to another inlet of the first ejector 302 and another inlet of the second ejector 306. Figure 3 As shown in (b), the hydrogen supply and circulation module may further include a sensor, which may be located at at least one of the following locations: the hydrogen supply inlet (e.g., as shown in Figure (b)). Figure 3 (b) As shown in B), hydrogen supply outlet (e.g., as shown in B). Figure 3 (b) As shown in A), the hydrogen recovery inlet (e.g., as shown in A) Figure 3 As shown in (b)C), a sensor senses the operating status of the fuel cell stack, and the hydrogen supply and circulation module controls the operating status of the first and second hydrogen supply branches based on the operating status of the fuel cell stack. Figure 3 As shown in (c), the sensor senses the operating status of the fuel cell stack and generates a control signal CM based on the operating status. According to the control signal CM, the sensor controls the operating status of the first hydrogen supply branch and the second hydrogen supply branch along the data transmission path shown by the dashed line. Figure 3 As shown, the hydrogen supply and circulation module employs a dual proportional valve and dual ejector solution to reduce power loss and improve system reliability. This is particularly beneficial in high-power power generation systems, as it can enhance system output efficiency. Specifically, during low-power operation, one ejector operates, while during high-power operation, both ejectors operate simultaneously. For example, during low-power operation, only one ejector operates (e.g., only the second ejector 306 operates), while during high-power operation, both ejectors operate simultaneously (i.e., the first ejector 302 and the second ejector 306 operate simultaneously).

[0100] In addition, the hydrogen supply and circulation module may also include a hydrogen pressure relief valve 310, the inlet of which is connected to a hydrogen supply outlet 314, and the outlet of which is connected to a hydrogen recovery outlet 320.

[0101] Figure 4 This is a schematic diagram illustrating a dry and humid air control module according to an embodiment of the present invention. Figure 4As shown, the dry and wet air control module includes a dry side inlet 408, a dry side outlet 410, a wet side inlet 412, and a wet side outlet 414. The dry side inlet 408 is connected to the outlet of the intercooler, the dry side outlet 410 is connected to the air inlet of the fuel cell stack, the wet side inlet 412 is connected to the air outlet of the fuel cell stack, and the wet side outlet 414 is connected to the inlet of the water separator. The dry and humid air control module includes a first intake branch, a second intake branch, a first outlet branch, and a second outlet branch. The dry-side inlet 408 of the dry and humid air control module is connected to the first end of both the first and second intake branches. The dry-side outlet 410 of the dry and humid air control module is connected to the second end of both the first and second intake branches. A dry air humidity valve 402 is installed in the first intake branch, and a humidifier 404 is installed in the second intake branch. The wet-side inlet 412 of the dry and humid air control module is connected to the first end of both the first and second outlet branches. The wet-side outlet 414 of the dry and humid air control module is connected to the second end of both the first and second outlet branches. A humid air humidity valve 406 is installed in the first outlet branch, and a humidifier 404 is installed in the second intake branch. This dry and humid air control module is an important component of a high-efficiency power generation system.

[0102] Figure 5 This is a schematic diagram illustrating a combined power supply structure according to an embodiment of the present invention. Figure 5As shown, the combined cooling, heating, and power (CCHP) power generation system includes CCHP system container 50A, CCHP system container 50B, and CCHP system container 50C. An air compression / expansion module, an intercooler, a dry / wet air control module, a hydrogen supply and circulation module, and a fuel cell stack are arranged within the CCHP system container. The fuel cell stack constitutes the main equipment of the CCHP power generation system, while the air compression / expansion module, intercooler, dry / wet air control module, and hydrogen supply and circulation module constitute the auxiliary equipment. CCHP system containers 50A, 50B, and 50C may have the same or similar structures. The cogeneration system container 50A is equipped with a main heat exchanger 502A and a main radiator 504A. The first inlet of the main heat exchanger 502A is connected to the coolant outlet of the fuel cell stacks 506A and 508A, and the first outlet of the main heat exchanger 502A is connected to the coolant inlet of the fuel cell stacks 506A and 508A. The main radiator 502A and the main heat exchanger 504A are connected in parallel and coupled. A first coolant flow valve 538A and a first cooling water pump 536A are installed in the connection channel between the first inlet of the main heat exchanger 502A and the coolant outlet of the fuel cell stacks 506A and 508A, and in the connection channel between the inlet of the main radiator and the coolant outlet of the fuel cell stack. The first valve of the first coolant flow valve 538A is connected to the first inlet of the main heat exchanger, and the second valve of the first coolant flow valve 538A is connected to the inlet of the main radiator. The pump operates according to the first coolant flow rate. The operating states of flow valve 538A and the first cooling water pump 536A can achieve one of the following operating modes: First operating mode: In the first operating mode, the first valve and the second valve of the first coolant flow valve 538A are simultaneously open, the first cooling water pump 536A is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, and the main heat exchanger 502A and the main radiator 504A are running simultaneously; Second operating mode: In the second operating mode, the first valve of the first coolant flow valve 538A is open, the second valve of the first coolant flow valve 538A is closed, the first cooling water pump 536A is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger 502A is running, and the main radiator 504A is not running.In the third operating mode, the first valve of the first coolant flow valve 538A is closed, the second valve of the first coolant flow valve 538A is open, the first cooling water pump 536A is running, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger 502A is not operating, and the main radiator 504A is operating. Furthermore, the second inlet of the main radiator 502A is connected to the heat exchange outlet 540, and the second outlet of the main radiator 502A is connected to the heat exchange inlet 542. In addition, the cogeneration system container 50A can also be equipped with an auxiliary heat exchanger 512A and an auxiliary radiator 514A. The first inlet of the auxiliary heat exchanger 512A is connected to the second outlet of the main heat exchanger 502A, and the first outlet of the auxiliary heat exchanger 512A is connected to the second inlet of the main heat exchanger 502A. The auxiliary radiator 514A is coupled in parallel with the auxiliary heat exchanger 512A. A second coolant flow valve 510A is installed in the connection channel between the first inlet of the auxiliary heat exchanger 512A and the second outlet of the main heat exchanger 502A. A third coolant flow valve 534A and a second cooling water pump 516A are installed in the connection channels between the auxiliary heat exchanger 512A and the auxiliary equipment, and in the connection channels between the auxiliary radiator 514A and the auxiliary equipment. The first valve of the third coolant flow valve 534A is connected to the second inlet of the auxiliary heat exchanger, and the second valve of the first coolant flow valve 538A is connected to the inlet of the auxiliary radiator. The configuration of the first coolant flow valve, the first cooling water pump, and the second cooling water pump is determined according to the configuration of the auxiliary heat exchanger 512A and the auxiliary equipment. The operation of the coolant flow valve 510A, the third coolant flow valve 534A, and the second cooling water pump 516A can achieve one of the following operating modes: Fourth operating mode, in which the first valve and the second valve of the first coolant flow valve 538A are opened simultaneously, the first cooling water pump 536A is running, the valve of the second coolant flow valve 510A is open, the first valve and the second valve of the third coolant flow valve 534A are opened simultaneously, the second cooling water pump 516A is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the first inlet of the auxiliary heat exchanger receives coolant from the second outlet of the corresponding main heat exchanger, the second inlet of the auxiliary heat exchanger receives coolant from the auxiliary equipment, the inlet of the auxiliary radiator receives coolant from the auxiliary equipment, and the main heat exchanger 502A, the auxiliary heat exchanger 514A, the main radiator 504A, and the auxiliary radiator 514A operate simultaneously;In the fifth operating mode, the first and second valves of the first coolant flow valve 538A are simultaneously open, the first cooling water pump 536A operates, the valve of the second coolant flow valve 510A is open, the first valve of the third coolant flow valve 534A is open, the second valve of the third coolant flow valve 534A is closed, the second cooling water pump 516A operates, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, and the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack. The first inlet of the auxiliary heat exchanger receives coolant from the second outlet of the corresponding main heat exchanger, and the second inlet of the auxiliary heat exchanger receives coolant from auxiliary equipment. The main heat exchanger 502A is in operation, the auxiliary heat exchanger 512A is in operation, the main radiator 504A is in operation, and the auxiliary radiator 514A is not in operation. In the sixth operating mode, the first and second valves of the first coolant flow valve 538A are simultaneously open, the first cooling water pump 536A is in operation, the valve of the second coolant flow valve 510A is open, and the third coolant flow valve 53... The first and second valves of 4A are closed, the second cooling water pump 516A is not running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger 502A is running, the auxiliary heat exchanger 512A is not running, the main radiator 504A is running, and the auxiliary radiator 514A is not running; in the seventh operating mode, the first valve of the first coolant flow valve 538A is closed, and the second valve of the first coolant flow valve 538A is closed. When the valves open, the first cooling water pump 536A operates, the second coolant flow valve 510A closes, the first valve of the third coolant flow valve 534A closes, and the second valve of the third coolant flow valve 534A opens, causing the second cooling water pump 516A to operate. The inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, and the inlet of the auxiliary radiator receives coolant from auxiliary equipment. The main heat exchanger 502A and auxiliary heat exchanger 512A are not operating; the main radiator 504A and auxiliary radiator 514A are operating. The main heat exchanger 502A and main radiator 504A are mainly used to cool the coolant in the fuel cell stacks 506A and 508A. Among them, the main radiator 504A can further improve the heat dissipation efficiency of the combined cooling, heating, and power (CCHP) power generation system. The auxiliary radiators 512A and auxiliary radiators 514A are mainly used to cool the heat generated by auxiliary components. For example, auxiliary components include intercoolers 518A and 532A, DC / DC converters 520A and 530A, air compression / expansion modules 524A and 526A, and air compressor controllers 522A and 528A.

[0103] The combined heat and power (CHP) system container 50B is equipped with a main heat exchanger 502B and a main radiator 504B. The first inlet of the main heat exchanger 502B is connected to the coolant outlet of the fuel cell stacks 506B and 508B, and the first outlet of the main heat exchanger 502B is connected to the coolant inlet of the fuel cell stacks 506B and 508B. The main radiator 502B and the main heat exchanger 504B are connected in parallel and coupled. A first cooling radiator is provided in the connection channel between the first inlet of the main heat exchanger 502B and the coolant outlet of the fuel cell stacks 506B and 508B. The refrigerant flow valve 538B and the first cooling water pump 536B, based on their operating states, can achieve one of the following operating modes: First operating mode: In the first operating mode, the main heat exchanger 502B and the main radiator 504B operate simultaneously; Second operating mode: In the second operating mode, the main heat exchanger 502B operates, while the main radiator 504B does not operate; Third operating mode: In the third operating mode, the main heat exchanger 502B does not operate, while the main radiator 504B operates. Furthermore, the second inlet of the main radiator 502B is connected to the heat exchange outlet 540, and the second outlet of the main radiator 502B is connected to the heat exchange inlet 542. In addition, the cogeneration system container 50B can also be equipped with an auxiliary heat exchanger 512BA and an auxiliary radiator 514B. The first inlet of the auxiliary heat exchanger 512B is connected to the second outlet of the main heat exchanger 502B, and the first outlet of the auxiliary heat exchanger 512B is connected to the second inlet of the main heat exchanger 502B. The auxiliary radiator 514B is coupled in parallel with the auxiliary heat exchanger 512B. A second coolant flow valve 510B is installed in the connection channel between the first inlet of the auxiliary heat exchanger 512B and the second outlet of the main heat exchanger 502B. A third coolant flow valve 534B and a second cooling water pump 516B are installed in the connection channel between the auxiliary heat exchanger 512B and the auxiliary radiator 514B. The configuration of the second coolant flow valve 510B, the third coolant flow valve 534B, and the second cooling water pump 514B is further configured accordingly. The 6B system operates in one of the following modes: Fourth operating mode: Main heat exchanger 502B, auxiliary heat exchanger 514B, main radiator 504B, and auxiliary radiator 514B operate simultaneously; Fifth operating mode: Main heat exchanger 502B, auxiliary heat exchanger 512B, and main radiator 504B operate, while auxiliary radiator 514B does not operate; Sixth operating mode: Main heat exchanger 502B operates, auxiliary heat exchanger 512B does not operate, main radiator 504B operates, and auxiliary radiator 514B does not operate; Seventh operating mode: Main heat exchanger 502B and auxiliary heat exchanger 512B do not operate, main radiator 504B operates, and auxiliary radiator 514B operates.The main heat exchanger 502B and main radiator 504B are primarily used to cool the coolant in the fuel cell stacks 506B and 508B. The main radiator 504BA can further improve the heat dissipation efficiency of the combined cooling, heating, and power (CCHP) system. The auxiliary radiators 512B and 514B are mainly used to cool the heat generated by auxiliary components. These auxiliary components include intercoolers 518B and 532B, DC / DC converters 520B and 530B, air compression / expansion modules 524B and 526B, and air compressor controllers 522B and 528B.

[0104] The combined heat and power (CHP) system container 50C is equipped with a main heat exchanger 502C and a main radiator 504C. The first inlet of the main heat exchanger 502C is connected to the coolant outlet of the fuel cell stacks 506C and 508C, and the first outlet of the main heat exchanger 502C is connected to the coolant inlet of the fuel cell stacks 506C and 508C. The main radiator 502C and the main heat exchanger 504C are connected in parallel and coupled. A first cooling radiator is provided in the connection channel between the first inlet of the main heat exchanger 502C and the coolant outlet of the fuel cell stacks 506C and 508C. The refrigerant flow valve 538C and the first cooling water pump 536C, based on their operating states, can achieve one of the following operating modes: First operating mode: In the first operating mode, the main heat exchanger 502C and the main radiator 504C operate simultaneously; Second operating mode: In the second operating mode, the main heat exchanger 502C operates, while the main radiator 504C does not operate; Third operating mode: In the third operating mode, the main heat exchanger 502C does not operate, while the main radiator 504C operates. Furthermore, the second inlet of the main radiator 502C is connected to the heat exchange outlet 540, and the second outlet of the main radiator 502C is connected to the heat exchange inlet 542. In addition, the cogeneration system container 50C can also be equipped with an auxiliary heat exchanger 512C and an auxiliary radiator 514C. The first inlet of the auxiliary heat exchanger 512C is connected to the second outlet of the main heat exchanger 502C, and the first outlet of the auxiliary heat exchanger 512C is connected to the second inlet of the main heat exchanger 502C. The auxiliary radiator 514C is coupled in parallel with the auxiliary heat exchanger 512C. A second coolant flow valve 510C is installed in the connection channel between the first inlet of the auxiliary heat exchanger 512C and the second outlet of the main heat exchanger 502C. A third coolant flow valve 534C and a second cooling water pump 516C are installed in the connection channel between the auxiliary heat exchanger 512C and the auxiliary radiator 514C. The configuration of the second coolant flow valve 510C, the third coolant flow valve 534C, and the second cooling water pump 514C is determined by the configuration of these components. The 6C system operates in one of the following modes: Fourth operating mode: Main heat exchanger 502C, auxiliary heat exchanger 514C, main radiator 504C, and auxiliary radiator 514C operate simultaneously; Fifth operating mode: Main heat exchanger 502C, auxiliary heat exchanger 512C, and main radiator 504C operate, while auxiliary radiator 514C does not operate; Sixth operating mode: Main heat exchanger 502C operates, auxiliary heat exchanger 512C does not operate, main radiator 504C operates, and auxiliary radiator 514C does not operate; Seventh operating mode: Main heat exchanger 502C and auxiliary heat exchanger 512C do not operate, main radiator 504C operates, and auxiliary radiator 514C operates.The main heat exchanger 502C and main radiator 504C are primarily used to cool the coolant in the fuel cell stacks 506C and 508C. The main radiator 504C can further improve the heat dissipation efficiency of the combined cooling, heating, and power (CCHP) system. The auxiliary radiators 512C and 514C are mainly used to cool the heat generated by auxiliary components. These auxiliary components include intercoolers 518C and 532C, DC / DC converters 520C and 530C, air compression / expansion modules 524C and 526C, and air compressor controllers 522C and 528C.

[0105] In addition, the main heat exchanger and auxiliary heat exchanger may include plate heat exchangers, which are equipped with a combined cooling, heating and power (CCHP) interface connected to user equipment to provide the heat generated by the CHP power generation system to the user equipment. The main radiator and auxiliary radiator may include cooling fans.

[0106] Figure 6 This is a graph showing the power generation efficiency of a combined cooling, heating and cooling power generation system according to an embodiment of the present invention and the power generation efficiency of a conventional combined cooling, heating and cooling power generation system. Figure 6 The horizontal axis in the graph represents current density, for example, in mA / cm². Figure 6 The vertical axis in the figure represents the system power efficiency. Figure 6 The solid line in the figure represents a high-efficiency combined cooling and heating power supply system according to an embodiment of the present invention. Figure 6 The dashed line in the diagram represents a conventional combined cooling and heating power supply system. Figure 7 This is a graph showing the overall efficiency of a combined cooling, heating and power generation system according to an embodiment of the present invention compared with the overall efficiency of a conventional combined cooling, heating and power generation system. Figure 7 The horizontal axis in the graph represents current density, for example, in mA / cm². Figure 7 The vertical axis in the figure represents the overall system efficiency. Figure 7 The solid line in the figure represents a high-efficiency combined cooling and heating power supply system according to an embodiment of the present invention. Figure 7 The dashed line in the diagram represents a conventional combined cooling, heating, and power (CCHP) system. For example... Figure 6 and 7 As shown, by adopting Figures 1 to 5The combined cooling, heating, and power generation system according to an embodiment of the present invention, as shown, employs an energy recovery scheme for both main and auxiliary equipment. The overall efficiency of the power generation system increases as the power consumption of the auxiliary components decreases. Furthermore, by increasing heat recovery in the auxiliary components, the system's heat recovery efficiency also improves. Currently, conventional combined cooling, heating, and power generation systems directly release heat energy into the atmosphere. Some projects recover the heat energy generated by the main equipment for residential heating, etc. With the large-scale application of fuel cell power generation systems in the future, the heat energy generated by auxiliary equipment will be considerable. Therefore, during product development, the heat energy generated by both the main and auxiliary equipment will be recovered and reused to improve the overall system efficiency.

[0107] The present invention provides a stationary, efficient, and scalable PEMFC fuel cell combined cooling, heating, and power system, including a fuel processing module, an air processing module, a cooling and heat dissipation module, and a power output module. This system achieves the following technical effects:

[0108] First, an air compression / expansion module with an expander is selected for exhaust energy recovery, and a water-air separation device is integrated at the inlet of the expander to reduce auxiliary power consumption and improve the power generation efficiency of the system.

[0109] Secondly, to control the air humidity of the fuel cell stack, a parallel ejector is used for hydrogen circulation, which reduces system power loss and improves system output efficiency.

[0110] Third, a design solution is proposed to recover the heat generated by the main / auxiliary components of the fuel cell.

[0111] Fourth, the integrated independent cooling fan supplements the heat dissipation of system components, making the power generation container system easier to expand.

[0112] Fifth, the power generation system reserves an external cogeneration interface for the plate heat exchanger and provides a comprehensive design solution.

[0113] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A combined cooling, heating and power (CCHP) power generation system based on fuel cells, characterized in that, The combined cooling, heating and power (CCHP) power generation system includes: an air filter (102), an air compression / expansion module (120), an intercooler (106-A), a dry and humid air control module (108-A), and a fuel cell stack (110-A). The air compression / expansion module includes an air compression unit (206), a water separator (208), and an air expansion unit (204), wherein the inlet of the air compression unit is connected to the air filter to receive filtered air, and the outlet of the air compression unit is connected to the inlet of the intercooler; and The dry and wet air control module includes a dry side inlet (408), a dry side outlet (410), a wet side inlet (412), and a wet side outlet (414). The dry side inlet is connected to the outlet of the intercooler, the dry side outlet is connected to the air inlet of the fuel cell stack, the wet side inlet is connected to the air outlet of the fuel cell stack, and the wet side outlet is connected to the inlet of the water separator.

2. The fuel cell-based combined cooling, heating and power generation system according to claim 1, characterized in that, The air outlet of the water separator is connected to the inlet of the air expansion unit, and the outlet of the air expansion unit is connected to the first outlet (4) of the combined cooling, heating and power generation system.

3. The fuel cell-based combined cooling, heating and power generation system according to claim 2, characterized in that, An air back pressure valve (202) is disposed between the outlet of the air expansion unit and the first outlet of the combined cooling, heating and power generation system. The liquid water outlet of the water separator is connected to the first outlet of the combined cooling, heating and power generation system. A drain valve (210) is disposed between the liquid water outlet of the water separator and the first outlet of the combined cooling, heating and power generation system.

4. The fuel cell-based combined cooling, heating and power generation system according to claim 3, characterized in that, The dry and humid air control module includes a first air intake branch, a second air intake branch, a first air outlet branch, and a second air outlet branch. The dry side inlet (408) of the dry and humid air control module is connected to the first end of the first air intake branch and the first end of the second air intake branch, respectively. The dry side outlet (410) of the dry and humid air control module is connected to the second end of the first air intake branch and the second end of the second air intake branch, respectively. A dry air humidity valve (402) is provided in the first air intake branch, and a humidifier (404) is provided in the second air intake branch. The wet side inlet (412) of the dry and humid air control module is connected to the first end of the first air outlet branch and the first end of the second air outlet branch, respectively. The wet side outlet (414) of the dry and humid air control module is connected to the second end of the first air outlet branch and the second end of the second air outlet branch, respectively. A wet air humidity valve (406) is provided in the first air outlet branch, and the humidifier (404) is provided in the second air intake branch.

5. The fuel cell-based combined cooling, heating and power generation system according to claim 4, characterized in that, The combined cooling, heating, and power (CCHP) power generation system further includes a hydrogen supply and circulation module (112-A). The hydrogen supply and circulation module includes a hydrogen supply inlet (316), a hydrogen supply outlet (314), a hydrogen recovery inlet (318), and a hydrogen recovery outlet (320). The hydrogen supply outlet is connected to the hydrogen inlet of the fuel cell stack, the hydrogen recovery inlet is connected to the hydrogen outlet of the fuel cell stack, and the hydrogen recovery outlet is connected to the second outlet (2) of the CCHP power generation system. The hydrogen supply and circulation module includes a first hydrogen supply branch and a second hydrogen supply branch. The hydrogen supply inlet is connected to the first end of the first hydrogen supply branch and the second hydrogen supply branch, respectively. At one end, the hydrogen supply outlet is connected to the second end of the first hydrogen supply branch and the second end of the second hydrogen supply branch, respectively. The first hydrogen supply branch is provided with a first ejector (302) and a first proportional valve (304). The inlet of the first proportional valve is connected to the hydrogen supply inlet, the outlet of the first proportional valve is connected to the inlet of the first ejector, and the outlet of the first ejector is connected to the hydrogen supply outlet. The second inlet branch is provided with a second ejector (306) and a second proportional valve (308). The inlet of the second proportional valve is connected to the hydrogen supply inlet, the outlet of the second proportional valve is connected to the inlet of the second ejector, and the outlet of the second ejector is connected to the hydrogen supply outlet.

6. The fuel cell-based combined cooling, heating and power generation system according to claim 5, characterized in that, The hydrogen supply and circulation module also includes a hydrogen circulation branch, in which a water-gas separator (312) is provided. The inlet of the water-gas separator is connected to the hydrogen recovery inlet, the liquid water outlet of the water-gas separator is connected to the hydrogen recovery outlet, and the gas outlet of the water-gas separator is connected to the other inlet of the first ejector and the other inlet of the second ejector, respectively.

7. The fuel cell-based combined cooling, heating and power generation system according to claim 6, characterized in that, The hydrogen supply and circulation module further includes a sensor disposed at at least one of the following locations: the hydrogen supply inlet, the hydrogen supply outlet, and the hydrogen recovery inlet, wherein the sensor senses the operating status of the fuel cell stack, and the hydrogen supply and circulation module controls the operating status of the first hydrogen supply branch and the second hydrogen supply branch based on the operating status of the fuel cell stack.

8. The fuel cell-based combined cooling, heating and power generation system according to claim 7, characterized in that, The hydrogen supply and circulation module also includes a hydrogen pressure relief valve (310), the inlet of which is connected to the hydrogen supply outlet and the outlet of which is connected to the hydrogen recovery outlet.

9. The fuel cell-based combined cooling, heating and power generation system according to claim 8, characterized in that, The air compression / expansion module, the intercooler, the dry and wet air control module, the hydrogen supply and circulation module, and the fuel cell stack are arranged in a cogeneration system container (50A). The fuel cell stack constitutes the main equipment of the cogeneration power generation system, while the air compression / expansion module, the intercooler, the dry and wet air control module, and the hydrogen supply and circulation module constitute auxiliary equipment. The cogeneration power generation system includes multiple cogeneration system containers connected in parallel. Each cogeneration system container is equipped with a main heat exchanger (502A) and a main radiator (504A). The first inlet of the main heat exchanger is connected to the fuel cell stack. A coolant outlet is provided. The first outlet of the main heat exchanger is connected to the coolant inlet of the fuel cell stack. The second inlet of the main heat exchanger is connected to the heat exchange inlet of the combined cooling, heating and power (CCHP) power generation system. The second outlet of the main heat exchanger is connected to the heat exchange outlet of the fuel cell stack. The main radiator is connected in parallel with the main heat exchanger. A first coolant flow valve (538A) and a first cooling water pump (536A) are provided in the connection channel between the first inlet of the main heat exchanger and the coolant outlet of the fuel cell stack, and in the connection channel between the inlet of the main radiator and the coolant outlet of the fuel cell stack. The first valve of the first coolant flow valve (538A) is connected to the first inlet of the main heat exchanger. The second valve of the first coolant flow valve (538A) is connected to the inlet of the main radiator. Based on the operating status of the first coolant flow valve and the first cooling water pump, one of the following operating modes is implemented: First operating mode: In the first operating mode, the first and second valves of the first coolant flow valve (538A) are simultaneously open, the first cooling water pump (536A) is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, and the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack; the main heat exchanger and the main radiator operate simultaneously. Second operating mode: In the second operating mode, the first coolant flow... In the first operating mode, the first valve of the flow valve (538A) is open, the second valve of the first coolant flow valve (538A) is closed, the first cooling water pump (536A) is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger is running, and the main radiator is not running; in the third operating mode, the first valve of the first coolant flow valve (538A) is closed, the second valve of the first coolant flow valve (538A) is open, the first cooling water pump (536A) is running, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger is not running, and the main radiator is running.

10. The fuel cell-based combined cooling, heating and power generation system according to claim 9, characterized in that, The main heat exchanger includes a plate heat exchanger, which is provided with a combined cooling, heating and power (CCHP) interface. The CCHP interface is connected to the user equipment to provide the user equipment with the heat generated during the operation of the CCHP power generation system. The main radiator includes a cooling fan.

11. The fuel cell-based combined cooling, heating and power generation system according to claim 10, characterized in that, An auxiliary heat exchanger (512A) and an auxiliary heat sink (514A) are arranged for each of the combined heat and power system containers, a first inlet of the auxiliary heat exchanger is connected to a second outlet of the corresponding main heat exchanger, a first outlet of the auxiliary heat exchanger is connected to the second inlet of the corresponding main heat exchanger, the auxiliary heat sink is coupled in parallel with the auxiliary heat exchanger, a second coolant flow valve (510A) is arranged in a connecting channel between the first inlet of the auxiliary heat exchanger and the second outlet of the corresponding main heat exchanger, a third coolant flow valve (534A) and a second cooling water pump (516A) are arranged in a connecting channel between the auxiliary heat exchanger and the auxiliary device and in a connecting channel between the auxiliary heat sink and the auxiliary device, a first valve of the third coolant flow valve (534A) is connected to the second inlet of the auxiliary heat exchanger, a second valve of the first coolant flow valve (538A) is connected to an inlet of the auxiliary heat sink, according to the operating states of the first coolant flow valve, the first cooling water pump, the second coolant flow valve, the third coolant flow valve and the second cooling water pump, one of the following operating modes is realized: a fourth operating mode, in the fourth operating mode, the first valve and the second valve of the first coolant flow valve (538A) are opened at the same time, the first cooling water pump (536A) operates, a valve of the second coolant flow valve (510A) is opened, the first valve and the second valve of the third coolant flow valve (534A) are opened at the same time, the second cooling water pump (516A) operates, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main heat sink receives coolant from the coolant outlet of the fuel cell stack, the first inlet of the auxiliary heat exchanger receives coolant from the second outlet of the corresponding main heat exchanger, the second inlet of the auxiliary heat exchanger receives coolant from the auxiliary device, the inlet of the auxiliary heat sink receives coolant from the auxiliary device, the main heat exchanger, the auxiliary heat exchanger, the main heat sink, the auxiliary heat sink operate at the same time;In the fifth operating mode, the first and second valves of the first coolant flow valve (538A) are simultaneously open, the first cooling water pump (536A) is running, the valve of the second coolant flow valve (510A) is open, the first valve of the third coolant flow valve (534A) is open, the second valve of the third coolant flow valve (534A) is closed, the second cooling water pump (516A) is running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the first inlet of the auxiliary heat exchanger receives coolant from the second outlet of the corresponding main heat exchanger, the second inlet of the auxiliary heat exchanger receives coolant from the auxiliary equipment, and the main heat exchanger is running, the auxiliary heat exchanger is running, the main radiator is running, and the auxiliary radiator is not running. In the sixth operating mode, the first and second valves of the first coolant flow valve (538A) are simultaneously open, the first cooling water pump (536A) is running, the valve of the second coolant flow valve (510A) is open, the first and second valves of the third coolant flow valve (534A) are closed, the second cooling water pump (516A) is not running, the first inlet of the main heat exchanger receives coolant from the coolant outlet of the fuel cell stack, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the main heat exchanger is running, the auxiliary heat exchanger is not running, the main radiator is running, and the auxiliary radiator is not running. In the seventh operating mode, the first valve of the first coolant flow valve (538A) is closed, the second valve of the first coolant flow valve (538A) is open, the first cooling water pump (536A) is running, the valve of the second coolant flow valve (510A) is closed, the first valve of the third coolant flow valve (534A) is closed, the second valve of the third coolant flow valve (534A) is open, the second cooling water pump (516A) is running, the inlet of the main radiator receives coolant from the coolant outlet of the fuel cell stack, the inlet of the auxiliary radiator receives coolant from the auxiliary equipment, the main heat exchanger is not running, the auxiliary heat exchanger is not running, the main radiator is running, and the auxiliary radiator is running.

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