A multi-module fuel cell power plant efficiency-based power regulation method

Abstract

The present application relates to fuel cell power station control technical field, disclose a kind of multi-module fuel cell power station based on efficiency power regulation method.The method first obtains power station request power P0And the minimum output power Pmin of single fuel cell power module, according to the numerical relationship of both to determine the number of opened module and initial power is divided equally;When opening 4 modules, real-time detection and comparison each module operating efficiency, calculate the difference between the highest and lowest efficiency, if the difference exceeds the set threshold, with half of the product of the divided power and the efficiency difference as the adjustment amount, increase power to high-efficiency module, reduce power to low-efficiency module, cycle adjustment until the module efficiency difference is within the set range.The present application can avoid module running below the minimum output power, expand the power range of power station, while making the efficiency of each module consistent, reducing the decay of low-efficiency module, prolonging the overall operation life of power station, solve the problem of poor efficiency and short life caused by the existing power division method.

Description

Technical Field

[0001] This invention relates to the field of fuel cell power plant control technology, and specifically to an efficiency-based power regulation method for a multi-module fuel cell power plant. Background Technology

[0002] As a clean and efficient energy supply device, a fuel cell power station typically consists of multiple independent power modules. A typical power station includes four fuel cell power modules (FCS1-FCS4) and auxiliary equipment such as a converter (DC / AC). Each fuel cell power module is an independent and complete fuel cell system, integrating an air supply device, a hydrogen regulation / circulation device, a thermal management device, and a control device, and has the ability to independently adjust its own operating conditions and operating status.

[0003] In existing technologies, when a fuel cell power station needs to output a specific total power, a power-sharing method is typically used to distribute the total power to each operating power module. However, this traditional method has significant drawbacks and shortcomings: Firstly, due to differences in manufacturing processes and usage losses among power modules in practical applications, their operating efficiencies are not consistent. Using a power-sharing method would cause high-efficiency and low-efficiency modules to output the same power, failing to fully utilize the advantages of high-efficiency modules and resulting in low overall efficiency of the entire power station. Secondly, when the total power demand is small, the power of a single module after power sharing will be lower than its minimum output power, causing the module to be unable to operate under suitable conditions. This not only affects the response speed but also accelerates module aging and shortens the overall lifespan of the power station. Furthermore, low-efficiency modules operating under the same power load as high-efficiency modules for a long time will experience faster degradation due to their own efficiency disadvantage, further exacerbating the performance decline of the power station.

[0004] Therefore, there is an urgent need for a control method that can dynamically adjust power allocation based on module efficiency and adapt to different power requirements in order to solve the problems of poor efficiency and shortened lifespan in existing technologies. Summary of the Invention

[0005] This invention aims to solve the following problems existing in the power regulation methods of multi-module fuel cell power plants: When the total power is small, the power distribution causes the operating power of a single module to be lower than the minimum output power, affecting the module's working status and response capability. When the module efficiency is inconsistent, the power distribution cannot achieve the optimal overall efficiency, and the inefficient modules degrade too quickly, shortening the power station's lifespan.

[0006] To achieve the above objectives, the present invention provides an efficiency-based power regulation method for a multi-module fuel cell power station, comprising the following steps: Step 1: Obtain the requested power P0 of the fuel cell power station and the minimum output power Pmin of a single fuel cell power module; Step 2: Determine the number of fuel cell power modules to be activated based on the numerical relationship between the requested power P0 and the minimum output power Pmin, and evenly distribute the requested power P0 to each activated fuel cell power module. Step 3: When the number of activated fuel cell power modules is 4, continuously detect and compare the actual operating efficiencies of these 4 fuel cell power modules, determine the highest operating efficiency ηn1 and its corresponding fuel cell power module n1, and simultaneously determine the lowest operating efficiency ηn2 and its corresponding fuel cell power module n2. Step 4: Calculate the difference between the highest operating efficiency ηn1 and the lowest operating efficiency ηn2, and compare this difference with the set efficiency difference A. Step 5: If the difference is greater than the set efficiency difference A, then use half of the product of the evenly distributed power when 4 modules are activated and the difference as the power adjustment amount. Increase this adjustment amount for fuel cell power module n1 and decrease it for fuel cell power module n2. Step 6: Repeat Steps 3 to 5 until the operating efficiency difference of the 4 fuel cell power modules is within the range of the set efficiency difference A.

[0007] Further, the specific logic for determining the number of activated fuel cell power modules in Step 2 is as follows: If P0 > 4Pmin, activate 4 fuel cell power modules, and the initial output power of each module is P0 / 4. If 3Pmin < P0 ≤ 4Pmin, activate 3 fuel cell power modules, and the initial output power of each module is P0 / 3. If 2Pmin < P0 ≤ 3Pmin, activate 2 fuel cell power modules, and the initial output power of each module is P0 / 2. If P0 ≤ 2Pmin, activate 1 fuel cell power module, and the output power of this module is P0.

[0008] Further, the value of the set efficiency difference A is 0.5% - 1.5%.

[0009] Further, the calculation formula for the power adjustment amount in Step 5 is: adjustment amount = (P0 / 4) × (ηn1 - ηn2) / 2, where P0 / 4 is the evenly distributed power when 4 fuel cell power modules are activated.

[0010] Further, when 3 fuel cell power modules are activated, each module operates at the initial output power after even distribution until the requested power P0 changes or the operating efficiency difference between modules exceeds the set efficiency difference A.

[0011] Furthermore, when two fuel cell power modules are turned on, each module maintains its initial output power after equal distribution until the requested power P0 changes or the difference in operating efficiency between modules exceeds the set efficiency difference A.

[0012] Furthermore, in step 6, the cycle of repeating steps 3 to 5 is 1-10 seconds.

[0013] Furthermore, the fuel cell power module is an independent and complete fuel cell system, which includes at least an air supply device, a hydrogen regulation / circulation device, a thermal management device, and a control device, and each module can independently adjust its own operating conditions and working conditions.

[0014] Furthermore, in step 3, the operating parameters of each fuel cell power module are collected through the control device built into each module, and the actual operating efficiency of each module is calculated based on the collected parameters. Furthermore, in step 5, after adjusting the power of fuel cell power modules n1 and n2, the output power of both modules is not lower than the minimum output power Pmin, and does not exceed their respective maximum rated output power.

[0015] The beneficial effects of this invention are: Expanding the operating power range: By dynamically adjusting the number of activated modules based on the relationship between requested power and minimum output power, it ensures that the output power of all operating modules is not lower than the minimum output power Pmin, avoiding modules operating under unsuitable conditions, thus extending the operating power of the fuel cell power station downwards to adapt to more power demand scenarios.

[0016] Optimize overall operating efficiency: By monitoring module efficiency in real time and dynamically adjusting power, high-efficiency modules can take on more power while low-efficiency modules reduce their power load, achieving a regulation effect of suppressing the strong and supporting the weak. This allows all modules to operate at similar efficiency points, fully leveraging the advantages of high-efficiency modules and improving the overall operating efficiency of the power plant.

[0017] Extending the lifespan of the power station: By reducing the operating load of inefficient modules, we can prevent them from rapidly degrading due to long-term overload operation, and at the same time, we can prevent the modules from aging under conditions below the minimum output power, thus significantly extending the overall operating life of the power station.

[0018] Precise and stable adjustment: The power adjustment amount is directly related to the power distribution and efficiency difference. The larger the efficiency difference, the larger the adjustment amount, and the smaller the efficiency difference, the smaller the adjustment amount. This avoids over-adjustment or under-adjustment, ensuring that the adjustment process is precise and stable, and making the module efficiency quickly converge. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a fuel cell power station.

[0020] Figure 2It is a logic flowchart for efficiency-based power regulation. Detailed implementation manners

[0021] To make the technical solution of the present invention clearer and more definite, the present invention will be described in detail below in conjunction with specific embodiments.

[0022] Refer to Figure 2 , the present invention provides an efficiency-based power regulation method for a multi-module fuel cell power station. The specific technical solution is as follows: Parameter acquisition: First, acquire the requested power P0 of the fuel cell power station and the minimum output power Pmin of a single fuel cell power module, where Pmin is the lowest output power threshold at which a single module can operate stably.

[0023] Number of modules to be turned on and initial power distribution: According to the numerical relationship between the requested power P0 and the minimum output power Pmin, determine the number of fuel cell power modules to be turned on and perform initial equal-power distribution. The specific logic is as follows: If P0 > 4Pmin, turn on 4 fuel cell power modules, and the initial output power of each module is P0 / 4; If 3Pmin < P0 ≤ 4Pmin, turn on 3 fuel cell power modules, and the initial output power of each module is P0 / 3; If 2Pmin < P0 ≤ 3Pmin, turn on 2 fuel cell power modules, and the initial output power of each module is P0 / 2; If P0 ≤ 2Pmin, turn on 1 fuel cell power module, and the output power of this module is P0.

[0024] Efficiency detection and comparison (when 4 modules are turned on): When 4 fuel cell power modules are turned on, collect operating parameters (such as input energy, output electric energy, etc.) through the control devices自带 by each module, calculate the actual operating efficiency of each module, and determine the highest operating efficiency ηn1 and its corresponding module n1 after comparison. At the same time, determine the lowest operating efficiency ηn2 and its corresponding module n2.

[0025] Efficiency difference judgment: Calculate the difference between the highest operating efficiency ηn1 and the lowest operating efficiency ηn2, and compare this difference with the set efficiency difference A (preferably with a value of 1%).

[0026] Power dynamic regulation: If the above efficiency difference is greater than the set efficiency difference A, perform power regulation in the following manner: Calculate the power regulation amount: Regulation amount = (P0 / 4) × (ηn1 - ηn2) / 2, where P0 / 4 is the equal-power when 4 modules are turned on; Increase the above adjustment amount for the highest efficiency module n1 and decrease the above adjustment amount for the lowest efficiency module n2. After adjustment, it is necessary to ensure that the output power of both modules is not lower than Pmin and does not exceed their respective maximum rated output power.

[0027] Cyclic optimization: After the power adjustment is completed, repeat steps 3 to 5, with the cycle period set to 1-10 seconds, until the difference in operating efficiency of the four modules is within the set efficiency difference A range, and then maintain the current power operation.

[0028] In addition, when two or three fuel cell power modules are turned on, each module maintains its initial output power after being evenly distributed until the requested power P0 changes or the difference in operating efficiency between modules exceeds the set efficiency difference A, at which point the corresponding adjustment logic is activated. Specific Implementation Example 1 See Figure 1 A multi-module fuel cell power station contains four independent fuel cell power modules (FCS1-FCS4). The minimum output power of a single module is Pmin=10kW, the maximum rated output power is 20kW, the set efficiency difference is A=1%, and the cycle adjustment period is 5 seconds.

[0030] When the power station receives a power request P0 = 45kW, the following steps are performed: Parameter acquisition: P0 = 45kW, Pmin = 10kW; Module activation and initial power allocation: Since 4Pmin = 40kW and P0 = 45kW > 40kW, 4 modules are activated, and the initial output power of each module = 45kW / 4 = 11.25kW; Efficiency testing and comparison: By collecting parameters from the control devices of each module, the efficiency of each module was calculated: FCS1 efficiency η1=42%, FCS2 efficiency η2=40%, FCS3 efficiency η3=41.5%, FCS4 efficiency η4=41%; the highest efficiency ηn1=42%, corresponding to module n1=FCS1, and the lowest efficiency ηn2=40%, corresponding to module n2=FCS2; Efficiency difference judgment: Efficiency difference = 42% - 40% = 2% > 1% (set efficiency difference A), power adjustment is required; Power adjustment: Calculated adjustment amount = (45kW / 4) × (2%) / 2 = (11.25kW) × 0.01 = 0.1125kW; Increase FCS1 by 0.1125kW, adjusted power = 11.25kW + 0.1125kW = 11.3625kW; Decrease FCS2 by 0.1125kW, adjusted power = 11.25kW - 0.1125kW = 11.1375kW; After adjustment, the power of both modules is within the range of 10kW-20kW. Optimize the loop: Repeat steps 3-5 after 5 seconds and check the efficiency again: FCS1 efficiency η1=41.8%, FCS2 efficiency η2=40.5%, FCS3 efficiency η3=41.5%, FCS4 efficiency η4=41%; Efficiency difference = 41.8%-40.5%=1.3%>1%, continue to adjust; Regulation amount = (45kW / 4) × (1.3%) / 2 ≈ 0.0731kW; Power after FCS1 adjustment = 11.3625kW + 0.0731kW ≈ 11.4356kW; Power after FCS2 adjustment = 11.1375kW - 0.0731kW ≈ 11.0644kW; Repeat the detection cycle until the efficiency difference between modules is ≤1%. For example, after the third cycle, if FCS1 efficiency = 41.5%, FCS2 efficiency = 41%, FCS3 efficiency = 41.3%, FCS4 efficiency = 41.2%, and the efficiency difference is 0.5% ≤1%, stop adjusting and maintain the current power operation.

[0031] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A power regulation method based on efficiency for a multi-module fuel cell power station, characterized in that, It includes the following steps: Step 1: Obtain the requested power P0 of the fuel cell power station and the minimum output power Pmin of a single fuel cell power module; Step 2: According to the numerical relationship between the requested power P0 and the minimum output power Pmin, determine the number of fuel cell power modules to be activated, and evenly distribute the requested power P0 to each activated fuel cell power module; Step 3: When the number of activated fuel cell power modules is 4, detect and compare the actual operating efficiencies of these 4 fuel cell power modules in real time, determine the highest operating efficiency ηn1 and its corresponding fuel cell power module n1, and at the same time determine the lowest operating efficiency ηn2 and its corresponding fuel cell power module n2; Step 4: Calculate the difference between the highest operating efficiency ηn1 and the lowest operating efficiency ηn2, and compare this difference with the set efficiency difference A; Step 5: If the difference is greater than the set efficiency difference A, then use half of the product of the evenly distributed power when 4 modules are activated and the difference as the power adjustment amount, increase the adjustment amount for the fuel cell power module n1, and decrease the adjustment amount for the fuel cell power module n2; Step 6: Repeat steps 3 to 5 until the operating efficiency difference of the 4 fuel cell power modules is within the range of the set efficiency difference A; 2. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, The specific logic for determining the number of activated fuel cell power modules in step 2 is as follows: If P0 > 4Pmin, activate 4 fuel cell power modules, and the initial output power of each module is P0 / 4; If 3Pmin < P0 ≤ 4Pmin, activate 3 fuel cell power modules, and the initial output power of each module is P0 / 3; If 2Pmin < P0 ≤ 3Pmin, activate 2 fuel cell power modules, and the initial output power of each module is P0 / 2; If P0 ≤ 2Pmin, activate 1 fuel cell power module, and the output power of this module is P0; 3. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, The value of the set efficiency difference A is 0.5% - 1.5%; 4. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, The calculation formula for the power adjustment amount in step 5 is: adjustment amount = (P0 / 4)×(ηn1 - ηn2) / 2, where P0 / 4 is the evenly distributed power when 4 fuel cell power modules are activated; 5. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 2, characterized in that, When 3 fuel cell power modules are activated, each module operates at the initial output power after even distribution until the requested power P0 changes or the operating efficiency difference between modules exceeds the set efficiency difference A; 6. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 2, characterized in that, When 2 fuel cell power modules are activated, each module operates at the initial output power after even distribution until the requested power P0 changes or the operating efficiency difference between modules exceeds the set efficiency difference A; 7. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, The cycle period for repeating steps 3 to 5 in step 6 is 1 - 10 seconds; 8. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, The fuel cell power module is an independent and complete fuel cell system, which at least includes an air supply device, a hydrogen regulation / circulation device, a thermal management device and a control device, and a single module can independently adjust its own operating conditions and working conditions; 9. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, In step 3, the control devices自带 by each fuel cell power module are used to collect the module operating parameters, and the actual operating efficiencies of each module are calculated based on the collected parameters.

10. The efficiency-based power regulation method for a multi-module fuel cell power station according to claim 1, characterized in that, After adjusting the power of fuel cell power modules n1 and n2 in step 5, the output power of both modules is not lower than the minimum output power Pmin, and does not exceed their respective maximum rated output power.

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