Seawater heat dissipation fuel cell ship system and temperature control method thereof

Abstract

The invention discloses a seawater heat dissipation fuel cell ship system and a temperature control method thereof. A water inlet integrated filtering grating located on the front side of the bottom face in the ship, a sea water pump and a water outlet located on the tail side of the bottom face in the ship are arranged in the ship. The water inlet integrated filtering grid, the sea water pump, the circulating system and the water outlet are connected in sequence. According to the seawater heat dissipation fuel cell ship system and the intelligent temperature control technology thereof, the fuel cell ship system is combined with the seawater heat dissipation device, the technical purpose that the heat exchanger transmits heat generated by the fuel cell system to seawater is achieved, an intelligent control system is designed, it is ensured that the system operates within the optimal temperature range, and the service life of the system is prolonged. The reliability and the stability of the fuel cell system are obviously improved, and the fuel cell system has wide application prospect and market value.

Description

Technical Field

[0001] The present invention belongs to the field of fuel cells, and relates to a fuel cell heat dissipation system and a control method, and specifically to a seawater heat dissipation fuel cell ship system and a temperature control method thereof. Background Art

[0002] With the continuous growth of global energy demand and the enhancement of environmental protection awareness, the development of clean energy technology has become a hot topic in today's society. Fuel cells, as an efficient and environmentally friendly energy conversion device, have received widespread attention and application due to their advantages such as high energy density, low emissions and high efficiency. Fuel cell technology has shown great application potential in the field of transportation, especially in ship power systems. Traditional ship power systems mainly rely on internal combustion engines, which are not only inefficient, but also emit a large amount of pollutants, causing serious impacts on the environment. In contrast, fuel cell ship systems can significantly reduce greenhouse gas and pollutant emissions, which is in line with the development trend of green shipping. However, fuel cells generate a lot of heat during operation. If the heat cannot be effectively dissipated, it will cause the system to overheat and affect the performance and life of the fuel cell. Therefore, how to dissipate heat efficiently has become a key issue in the design of fuel cell ship systems.

[0003] Existing fuel cell ship systems usually use air cooling or closed liquid cooling systems. These cooling methods have some significant disadvantages, such as low heat dissipation efficiency, which cannot quickly and effectively dissipate the heat generated by the fuel cell, causing the system to overheat and affect the performance and life of the fuel cell. The air cooling system requires additional energy to drive the fan to dissipate heat, which increases the energy consumption of the system and reduces the overall energy utilization efficiency. In addition, due to the low specific heat capacity of air and limited heat dissipation efficiency, it is difficult to meet the heat dissipation requirements of high-power fuel cells. Although the closed liquid cooling system has a good heat dissipation effect, its structure is complex, difficult to maintain, and requires additional energy to drive the cooling device, which increases the energy consumption of the system. The cooling system in the prior art usually lacks intelligent control and cannot be dynamically adjusted according to the real-time temperature changes of the fuel cell system, resulting in unstable cooling effect and difficulty in keeping the system within the optimal operating temperature range.

[0004] In the ship environment, seawater, as a natural cooling medium, has the advantages of high specific heat capacity, stable temperature and abundant resources. Using seawater for heat dissipation is an ideal solution. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides a seawater heat dissipation fuel cell ship system and a temperature control method thereof, which solve the defects in the prior art, improve the heat dissipation efficiency, energy utilization and intelligence of the system, reduce the maintenance difficulty and cost, and open up new ideas for the heat dissipation of the fuel cell ship system.

[0006] The present invention combines the seawater heat dissipation fuel cell ship system and its intelligent temperature control technology through the fuel cell ship system and the seawater heat dissipation device, thereby achieving the technical purpose of transferring the heat generated by the fuel cell system to the seawater through the heat exchanger, and designs an intelligent control system to ensure that the system operates within the optimal temperature range, which significantly improves the reliability and stability of the fuel cell system and has broad application prospects and market value.

[0007] The technical solution of the present invention is as follows.

[0008] A seawater heat dissipation fuel cell ship system, wherein a water inlet integrated filter grid located at the front side of the ship's inner bottom, a seawater pump and a water outlet located at the rear side of the ship's inner bottom are arranged inside the ship; the water inlet integrated filter grid, seawater pump, circulation system and water outlet are connected in sequence;

[0009] The circulation system consists of a heat exchanger, a three-way valve and a fuel cell system. The heat medium outlet of the heat exchanger is connected to the three-way valve and the cooling water inlet of the fuel cell system; the cooling water outlet of the fuel cell system is connected to the heat medium inlet of the heat exchanger, and one outlet of the three-way valve is connected to the pipeline between the fuel cell system and the heat exchanger through a pipeline.

[0010] Furthermore, the present invention also includes a one-way valve; the one-way valve is arranged on the pipeline between the seawater pump and the circulation system.

[0011] Furthermore, the present invention also includes an anti-backflow valve; the anti-backflow valve is arranged on the pipeline between the circulation system and the water outlet.

[0012] Furthermore, the seawater pump is connected to the cold medium inlet of the heat exchanger.

[0013] Furthermore, the cold medium outlet of the heat exchanger is connected to the water outlet.

[0014] In the present invention, a seawater-cooled fuel cell ship system, as shown in Figure 1, is mainly completed by the following components working together: an inlet integrated filter grille, a seawater pump, a check valve, a heat exchanger, a three-way valve, a fuel cell system, a backflow prevention valve, and an outlet. The inlet integrated filter grille should be located at the front of the bottom of the ship's hull to utilize the forward speed during ship operation to promote the natural inflow of seawater, and is connected to the seawater pump through an inlet pipe. The inlet is circular to ensure sufficient seawater flow. The inlet integrated filter grille is used to prevent debris from entering the cooling system. The seawater pump is located between the inlet and the check valve and is responsible for pumping seawater and delivering it to the heat exchanger through the check valve. The check valve is located between the seawater pump and the heat exchanger to isolate the seawater from flowing into the heat exchanger. The heat exchanger is located in the middle of the ship's hull and is used to transfer the heat generated by the fuel cell system to the seawater flowing through it. The fuel cell system is located near the heat exchanger, generates heat and transfers the heat to the seawater through the heat exchanger. The check valve is located between the heat exchanger and the outlet to prevent seawater from flowing back when the ship stops or reverses. The outlet integrated filter grille is located at the rear of the bottom of the ship's hull and is connected to the backflow prevention valve to the heat exchanger through a drain pipe to discharge the heated seawater. The outlet integrated filter grille is used to prevent debris from entering the cooling system. This system realizes the heat dissipation of the fuel cell system through effective heat exchange and seawater circulation, ensuring that the system operates within an appropriate temperature range.

[0015] Based on the above, the following is the seawater-cooled fuel cell ship system and the temperature control method of the seawater-cooled fuel cell ship system, as shown in Figure 2.

[0016] It includes the following steps:

[0017] S1: Calibrate the optimal operating water temperature T1 of the fuel cell;

[0018] S2: Real-time collect the water temperature T2 entering the stack;

[0019] S3: Compare the current water temperature T2 entering the fuel cell stack with the optimal operating water temperature T1;

[0020] If the current water temperature T2 entering the stack is less than the optimal operating water temperature T1 and T2 is less than T3, then perform the following actions: close the check valve, do not start the seawater pump, and set the opening of the three-way valve to 0; at this time, the coolant is in a completely internal circulation state, and quickly raise the stack water temperature to the optimal temperature; if T3 < T2 < T1, control the opening of the three-way valve according to the real-time water temperature entering the stack. As the temperature increases, specifically control the opening of the three-way valve through PI control; the PI controller dynamically adjusts the opening of the three-way valve according to the real-time monitored water temperature T2 entering the stack to keep the system in the optimal operating state. The value range of T3 is 50°C to 57°C, preferably 55°C.

[0021] The specific output calculation process is as follows

[0022] (1) The output μ(t) of the PI controller is:

[0023]

[0024] Among them, K p is the proportional gain, K i is the integral gain, e(t) is the current error, defined as the difference between the target temperature and the actual temperature: e(t) = T1-T2(t), ∫0 t e(τ)dτ is the integral of the error function e(τ) over the interval 0 to t.

[0025] (2) According to the output of the PI controller, the opening degree K of the three-way valve can be expressed as:

[0026]

[0027] Among them, K min is the minimum opening of the three-way valve, K max is the maximum opening of the three-way valve, μ max is the maximum output of the controller.

[0028] (3) Combined with the above formula, the opening of the three-way valve can be dynamically adjusted through the output of the PI controller:

[0029]

[0030] Where, T2(t) is the real-time temperature, It is the integral of the error function T1-T2(τ) in the interval 0 to t.

[0031] The opening of the three-way valve is gradually increasing. At this time, the coolant circulates inside and outside at the same time. By gradually mixing the lower-temperature water in the external circulation pipeline with the higher-temperature water in the internal circulation, the temperature of the coolant is reduced, thereby reducing the operating temperature of the fuel cell and ensuring that the real-time temperature of the fuel cell remains within the optimal operating range.

[0032] When the water temperature entering the stack T2 is greater than the optimal operating water temperature T1, and the three-way valve opening is equal to 100%, the one-way valve (3) is opened and the seawater pump (2) is started, wherein the speed of the seawater pump (2) is realized through closed-loop PI control; at this time, it is in an external circulation state, and the speed of the seawater pump is controlled according to the real-time water temperature entering the stack, and the water flow rate is adjusted to speed up and transfer the heat generated by the fuel cell system to the flowing seawater to maintain the fuel cell running at the optimal operating temperature. The PI controller dynamically adjusts the speed of the seawater pump according to the real-time monitored water temperature entering the stack T2 to keep the system in the optimal operating state. The specific output calculation process is as follows

[0033] (1) The output μ(t) of the PI controller is

[0034]

[0035] Where Kp is the proportional gain, Ki is the integral gain, and e(t) is the current error, defined as the difference between the target temperature and the actual temperature: e(t) = T1-T2(t)

[0036] (2) According to the output of the PI controller, the speed R of the seawater pump can be expressed as:

[0037] Where: R min is the minimum speed of the seawater pump, R max is the maximum speed of the seawater pump, μ max is the maximum output of the controller.

[0038] (3) Combined with the above formula, the speed of the seawater pump can be dynamically adjusted through the output of the PI controller:

[0039]

[0040] In the above method, the inner circulation is that the inner circulation pipeline is connected and the outer circulation pipeline is closed, and the opening of the three-way valve is 0; the coolant flows through the inner circulation pipeline, and the cooling water outlet of the fuel cell system is connected to the cooling water inlet of the fuel cell system through a pipeline, such as Figure 1 The inner loop is shown by the dotted line.

[0041] In the above method, the external circulation means that the external circulation pipeline is connected while the internal circulation pipeline is closed, at this time the opening of the three-way valve is 100%, the cooling water outlet of the fuel cell system is connected to the heat medium inlet of the heat exchanger through a pipeline, and the heat medium outlet of the heat exchanger is connected to the cooling water inlet of the fuel cell system through a pipeline; the coolant flows through the external circulation pipeline, such as Figure 1 The inner and outer cycles are shown by dotted lines.

[0042] Among the above methods, PI control, i.e. proportional-integral control, is a simple and effective linear control method, which is widely used in various industrial control systems. By properly adjusting the proportional gain and integral gain, the PI controller can quickly respond to error changes, eliminate steady-state errors, and ensure that the controlled variable is stable at the set value.

[0043] Compared with the prior art, the advantages of the present invention are:

[0044] 1. The present invention utilizes a fuel cell ship system combined with a seawater heat dissipation device to realize an innovative design in which a heat exchanger transfers the heat generated by the fuel cell system to the seawater.

[0045] 2. The present invention uses seawater circulation and heat exchange to effectively dissipate heat from the fuel cell system, thereby ensuring the key technical point of stable operation of the system.

[0046] 3. The present invention utilizes seawater as a cooling medium, which is an innovative application to improve energy efficiency and reduce system operating costs.

[0047] 4. The seawater circulation system provided by the present invention ensures that seawater can effectively flow through the heat exchanger, thereby improving heat dissipation efficiency.

[0048] 5. The intelligent control system provided by the present invention automatically adjusts the opening of the three-way valve and the speed of the seawater pump according to the temperature data of the fuel cell system to keep the system within a stable operating temperature range.

[0049] 6. The present invention significantly improves the performance and reliability of the fuel cell system and has broad application prospects and market value. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a schematic diagram of the seawater heat dissipation fuel cell ship system of the present invention;

[0051] Figure 2 This is a schematic diagram of the intelligent temperature control of the seawater heat dissipation fuel cell ship system of the present invention.

[0052] The components in the figure are as follows:

[0053] The water inlet integrates a filter grille 1, a seawater pump 2, a one-way valve 3, a heat exchanger 4, a three-way valve 5, a fuel cell system 6, an anti-backflow valve 7, and a water outlet 8. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Example 1

[0056] like Figure 1 As shown, a seawater heat dissipation fuel cell ship system is provided inside the ship with a water inlet integrated filter grille 1 located on the front side of the bottom surface of the ship, a one-way valve 3, a heat exchanger 4, a three-way valve 5, a fuel cell system 6, a backflow prevention valve 7 and a water outlet 8 located on the rear side of the bottom surface of the ship; the water inlet integrated filter grille 1, the seawater pump 2, the one-way valve 3, the heat exchanger 4, the backflow prevention valve 7 and the water outlet 8 are connected in sequence;

[0057] The heat medium outlet of the heat exchanger 4 is connected to the three-way valve 5 and the cooling water inlet of the fuel cell system 6; the cooling water outlet of the fuel cell system 6 is connected to the heat medium inlet of the heat exchanger 4, and one outlet of the three-way valve 5 is connected to the pipeline between the fuel cell system 6 and the heat exchanger 4 through a pipeline.

[0058] It should be noted that the internal circulation in this embodiment is as Figure 1 shown. Close the one-way valve 3, do not start the seawater pump 2, and set the opening of the three-way valve to 0; at this time, the coolant is in the internal circulation state, that is, the coolant passes through the three-way valve 5 from the cooling water outlet of the fuel cell system 6 and finally returns to the fuel cell system 6 from the cooling water inlet of the fuel cell system 6. The external circulation in this embodiment is as Figure 1 shown, which means that the external circulation pipeline is connected while the internal circulation pipeline is closed. At this time, the opening of the three-way valve is 100%. The cooling water outlet of the fuel cell system 6 is connected to the heat medium inlet of the heat exchanger 4 through a pipeline, and the heat medium outlet of the heat exchanger 4 is connected to the cooling water inlet of the fuel cell system 6 through a pipeline.

[0059] Embodiment 2

[0060] This embodiment is based on the seawater-cooled fuel cell ship system in Embodiment 1 and includes the following steps:

[0061] S1: Calibrate the optimal operating water temperature T1 of the fuel cell to be 69 °C

[0062] S2: Real-time collect the water temperature T2 entering the stack to be 35 °C

[0063] S3: Compare the current water temperature T2 entering the fuel cell stack with the optimal operating water temperature T1, and T2 is less than T3 55 °C, that is, T2 < 55 °C < T1, then perform the following actions: close the one-way valve 3, do not start the seawater pump 2, and set the opening of the three-way valve 5 to 0. At this time, the coolant is in a fully internal circulation state to quickly raise the stack water temperature to the optimal temperature.

[0064] Embodiment 3

[0065] This embodiment is based on the seawater-cooled fuel cell ship system in Embodiment 2 and includes the following steps:

[0066] S1: Calibrate the optimal operating water temperature T1 of the fuel cell to be 69 °C

[0067] S2: Real-time collect the water temperature T2 entering the stack to be 57 °C, and this temperature gradually rises from 35 °C to 57 °C;

[0068] S3: Compare the size of the current water temperature T2 entering the fuel cell stack with the optimal operating water temperature T1. And when T2 is greater than T3 by 55 °C, that is, 55 °C < T2 < T1, then perform the following actions: close the one-way valve 3 and do not start the seawater pump 2. As the temperature increases, the opening degree of the specific control three-way valve is realized through PI control. At this time, the internal and external circulation of the coolant is carried out simultaneously. By gradually mixing the water with a lower temperature in the external circulation pipeline with the water with a higher temperature in the internal circulation, the temperature of the coolant is reduced, so that the operating temperature of the fuel cell drops, ensuring that the real-time temperature of the fuel cell remains within the optimal operating range.

[0069] Example 4

[0070] This embodiment is based on the seawater-cooled fuel cell ship system in Embodiment 2 and includes the following steps:

[0071] S1: Calibrate the optimal operating water temperature T1 of the fuel cell to 69 °C;

[0072] S2: Real-time collect the water temperature T2 entering the stack as 70 °C;

[0073] S3: If T2 > T1 and the opening degree of the three-way valve is equal to 100%, then perform the following actions: open the one-way valve and start the seawater pump, where the rotational speed of the seawater pump is realized through closed-loop PI control. At this time, it is in the external circulation state. According to the real-time water temperature entering the stack, the rotational speed of the seawater pump is controlled to quickly adjust the water flow rate, and then the heat generated by the fuel cell system is transferred to the flowing seawater to maintain the fuel cell operating at the optimal operating temperature.

[0074] Partial data collected in the example

[0075] Water temperature in the pile T2 / ℃ 50 57 60 62 64 65 68 69 71 72 69 Three-way valve opening % 0 12 42 68 85 91 100 100 100 100 100 Seawater pump speed / rpm 0 0 0 0 0 0 1511 1800 2510 3100 1550

[0076] As mentioned above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A seawater heat dissipation fuel cell ship system, characterized in that: An integrated filter grille (1) for water inlet, a seawater pump (2), and a water outlet (8) located at the rear side of the inner bottom surface of the ship are provided inside the ship; the integrated filter grille (1) for water inlet, the seawater pump (2), the circulation system, and the water outlet (8) are connected in sequence. The circulation system consists of a heat exchanger (4), a three-way valve (5), and a fuel cell system (6). The heat medium outlet of the heat exchanger (4) is connected to the cooling water inlet of the three-way valve (5) and the fuel cell system (6); the cooling water outlet of the fuel cell system (6) is connected to the heat medium inlet of the heat exchanger (4), and one outlet of the three-way valve (5) is connected to the pipeline between the fuel cell system (6) and the heat exchanger (4) through a pipeline.

2. A seawater heat dissipation fuel cell ship system as claimed in claim 1, characterized in that: It also includes a check valve (3); the check valve (3) is arranged on the pipeline between the seawater pump (2) and the circulation system.

3. A seawater heat dissipation fuel cell ship system as claimed in claim 1, characterized in that: It also includes a backflow prevention valve (7); the backflow prevention valve (7) is arranged on the pipeline between the circulation system and the water outlet (8).

4. A seawater heat dissipation fuel cell ship system as claimed in claim 1, characterized in that: The seawater pump (2) is connected to the cold medium inlet of the heat exchanger (4).

5. A seawater heat dissipation fuel cell ship system as claimed in claim 1, characterized in that: The cold medium outlet of the heat exchanger (4) is connected to the water outlet (8).

6. A temperature control method using the seawater heat dissipation fuel cell ship system according to any one of claims 1 to 5, characterized in that: It includes the following steps: S1: Calibrate the optimal operating water temperature T1 of the fuel cell. S2: Real-time collect the water temperature T2 entering the stack. S3: Compare the current water temperature T2 entering the fuel cell stack with the optimal operating water temperature T1. If the current water temperature T2 entering the stack is less than the optimal operating water temperature T1 and T2 is less than T3, then perform the following actions: close the check valve (3), do not start the seawater pump (2), and set the opening of the three-way valve (5) to 0; at this time, the coolant is in a completely internal circulation state, and quickly raise the temperature of the fuel cell stack to the optimal temperature; if T3 < T2 < T1, control the opening of the three-way valve according to the real-time water temperature entering the stack. As the temperature increases, specifically control the opening of the three-way valve through PI control; the opening of the three-way valve is gradually increasing. At this time, the internal and external circulation of the coolant is carried out simultaneously. By gradually mixing the water with a lower temperature in the external circulation pipeline and the water with a higher temperature in the internal circulation, the temperature of the coolant is reduced, so that the operating temperature of the fuel cell drops, ensuring that the real-time temperature of the fuel cell remains within the optimal operating range. If the current water temperature T2 entering the stack is greater than the optimal operating water temperature T1 and the opening of the three-way valve is equal to 100%, then perform the following actions: open the check valve (3), start the seawater pump (2), and the speed of the seawater pump (2) is achieved through closed-loop PI control; at this time, it is in the external circulation state, control the speed of the seawater pump according to the real-time water temperature entering the stack, and accelerate the adjustment of the water flow rate, so as to transfer the heat generated by the fuel cell system to the flowing seawater to maintain the fuel cell operating at the optimal operating temperature.

7. The temperature control method according to claim 6, characterized in that: The internal circulation means that the internal circulation pipeline is connected while the external circulation pipeline is closed. At this time, the opening of the three-way valve (5) is 0; the coolant flows through the internal circulation pipeline, and the cooling water outlet of the fuel cell system (6) is connected to the cooling water inlet of the fuel cell system (6) through a pipeline.

8. The temperature control method according to claim 6, characterized in that: The external circulation means that the external circulation pipeline is connected while the internal circulation pipeline is closed. At this time, the opening degree of the three-way valve is 100%. The cooling water outlet of the fuel cell system (6) is connected to the heat medium inlet of the heat exchanger (4) through a pipeline, and the heat medium outlet of the heat exchanger (4) is connected to the cooling water inlet of the fuel cell system (6) through a pipeline; the coolant flows through the external circulation pipeline.

9. The temperature control method according to claim 6, characterized in that: The PI control, i.e. proportional-integral control, is a simple and effective linear control method, which is widely used in various industrial control systems. By reasonably adjusting the proportional gain and the integral gain, the PI controller can quickly respond to error changes, eliminate steady-state errors, and ensure that the controlled variable is stable at the set value.

10. The temperature control method according to claim 6, characterized in that: In S3, the PI controller dynamically adjusts the opening of the three-way valve according to the real-time monitored inlet water temperature T2 to keep the system in the best operating state; the specific output calculation process is as follows: (1) The output μ(t) of the PI controller is μ(t)=K p ·e(t)+K i ·∫0 t e(τ)dτ Among them, K p is the proportional gain, K i is the integral gain, e(t) is the current error, defined as the difference between the target temperature and the actual temperature: e(t) = T1-T2(t) (2) According to the output of the PI controller, the opening degree K of the three-way valve can be expressed as: Where: K min is the minimum opening of the three-way valve, K max : Maximum opening of the three-way valve, μ max : Maximum output of the controller; (3) Combined with the above formula, the opening of the three-way valve can be dynamically adjusted through the output of the PI controller: In S2, the PI controller dynamically adjusts the speed of the seawater pump according to the real-time monitored inlet water temperature T2 to keep the system in the best operating state. The specific output calculation process is as follows (1) The output μ(t) of the PI controller is: μ(t)=K p ·e(t)+K i ·∫0 t e(τ)dτ Where Kp is the proportional gain, Ki is the integral gain, and e(t) is the current error, which is defined as the difference between the target temperature and the actual temperature: e(t) = T1-T2(t); (2) According to the output of the PI controller, the speed R of the seawater pump can be expressed as: Where: R min is the minimum speed of the seawater pump, R max is the maximum speed of the seawater pump, μ max is the maximum output of the controller; (3) Combined with the above formula, the speed of the seawater pump can be dynamically adjusted through the output of the PI controller:

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