Fuel Cell Reformer Control via Mixed Gas Concentration Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The complexity of existing fuel cell systems due to the need for separate water and oxygen-containing fuel storage tanks leads to a cumbersome configuration, and the challenge of maintaining optimal fuel gas supply to the fuel cell stack, particularly with ethanol-based systems where concentration changes affect reforming performance.
Innovation Solution
A fuel cell system with a single tank storing a mixture of oxygen-containing fuel and water, where the controller adjusts the operating temperature and gas supply based on detected fuel concentration and temperature differences to optimize reforming performance, using sensors and control methods to manage the concentration of oxygen-containing fuel in the reformer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate water storage tank and fuel tank are used, then steam generation and fuel supply can be controlled independently, but the system configuration becomes complex
Solution Approach 1:
The patent combines the water storage tank and fuel storage tank into a single integrated tank that stores both water and oxygen-containing fuel separately. This merging of storage functions reduces the number of components and simplifies the overall system configuration while maintaining the ability to independently control steam generation and fuel supply through separate supply lines and control mechanisms.
2Device complexity
If single tank storing mixture of oxygen-containing fuel and water is used, then system configuration is simplified, but maintaining optimal fuel concentration becomes difficult
Solution Approach 1:
The patent incorporates a concentration detection device that continuously monitors the concentration of oxygen-containing fuel in the reformer. The controller receives this feedback information and adjusts the supply amounts of water and fuel to maintain optimal concentration levels. This closed-loop feedback control ensures stable fuel gas supply while using a simplified single-tank configuration.
Solution Approach 2:
The system dynamically adjusts operating parameters including the supply amounts of water and oxygen-containing fuel, as well as the operating temperature of the reformer, based on detected concentration levels. By changing these parameters in response to concentration variations, the system maintains optimal reforming conditions despite using a mixed-storage approach.
3Ease of operation
If fuel concentration in reformer is not controlled, then system operation is simple, but reforming performance deteriorates
Solution Approach 1:
The system uses the concentration detection device to automatically monitor and assess the fuel concentration in the reformer. This self-monitoring capability allows the system to autonomously determine when concentration adjustments are needed, maintaining optimal reforming performance without requiring complex manual intervention or sophisticated control algorithms.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach simplifies the fuel cell system configuration by eliminating the need for separate tanks and ensures a stable fuel gas supply to the fuel cell stack, maintaining efficient power generation by dynamically adjusting the reformer's operating conditions based on real-time fuel concentration and temperature data.
Implementation Method 1
a reformer (24) that reforms the mixed gas and generates the fuel gas
Implementation Method 2
an evaporator (23) that evaporates the aqueous solution and generates the mixed gas
Implementation Method 3
a fuel cell that receives supplies of the fuel gas and the oxidant gas and generates power
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fuel cell system 100 that supplies fuel gas and oxidant gas to a fuel cell stack 10 and causes the fuel cell stack 10 to generate power includes a tank 21 that stores aqueous solution containing oxygen-containing fuel, and a reformer 24 that reforms mixed gas obtained as the aqueous solution is vaporized, and generates the fuel gas. The fuel cell system 100 also includes a fuel pump 22 that supplies the mixed gas to the reformer 24, a discharged gas control valve 42 that heats the reformer 24, a sensor 51 that estimates or detects a concentration of the mixed gas supplied to the reformer 24, and a controller 50 that controls the fuel pump 22 and the discharged gas control valve 42 so that the fuel cell stack 10 generates power. When the consternation of the oxygen-contained fuel gas is high, compared to when the concentration is low, the controller 50 increases a thermal dose to the reformer 24 from the discharged gas control valve 42 or increases a supply amount of the mixed gas to the reformer 24 from the fuel pump 22.