Fuel Cell Anode Hydrogen Injection Feedback Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for determining when to inject hydrogen into the anode side of a fuel cell stack in a fuel cell vehicle when off are inefficient, as they rely on time-based schedules that do not account for varying hydrogen concentrations, leading to potential damage from air/hydrogen fronts and reduced system reliability and efficiency.
Innovation Solution
A system and method using a gas concentration model to estimate hydrogen levels in the anode side of the fuel cell stack, injecting hydrogen when the concentration falls below a threshold and adjusting based on feedback to maintain a desired concentration, thereby minimizing hydrogen/air fronts and optimizing start-up conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If time-based schedules are used to determine hydrogen injection, then the control system is simple, but the system reliability deteriorates due to inaccurate hydrogen concentration estimation
Solution Approach 1:
The patent implements a feedback mechanism using a gas concentration model that continuously estimates hydrogen concentration in the anode based on historical data and system parameters. The controller uses this feedback to dynamically adjust injection timing and duration, replacing fixed time-based schedules with adaptive concentration-based control that responds to actual system conditions.
Solution Approach 2:
The gas concentration model performs preliminary estimation of hydrogen concentration before injection decisions are made. By predicting the current hydrogen level using historical data and system parameters, the controller can proactively determine the optimal injection timing rather than relying on predetermined time schedules, improving reliability while maintaining reasonable complexity.
2Reliability
If hydrogen injection is performed frequently to maintain concentration, then reliability improves, but fuel consumption increases
Solution Approach 1:
The feedback mechanism provides accurate real-time estimation of hydrogen concentration, enabling the controller to inject hydrogen only when concentration falls below the threshold. This precise control eliminates unnecessary injections that would occur with conservative time-based scheduling, maintaining reliability while reducing fuel consumption through demand-based injection.
Solution Approach 2:
The system dynamically adjusts injection parameters (timing and duration) based on the estimated hydrogen concentration and system operating conditions. By changing injection parameters to match actual demand rather than using fixed schedules, the system achieves reliable hydrogen level maintenance with minimal fuel consumption.
3Device complexity
If hydrogen concentration is not monitored accurately, then device complexity is reduced, but harmful factors increase due to air/hydrogen fronts
Solution Approach 1:
The gas concentration model provides continuous feedback on hydrogen concentration levels, enabling the controller to detect when concentration drops and trigger injection before air/hydrogen fronts form. This monitoring feedback system, while adding some complexity, prevents the harmful effects of air intrusion by maintaining hydrogen concentration above critical thresholds.
Solution Approach 2:
The model performs preliminary assessment of hydrogen concentration trends using historical data, allowing the system to take preventive action before air/hydrogen fronts develop. By predicting concentration drops and triggering early injection, the system prevents harmful conditions without requiring complex real-time sensing infrastructure.
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 reduces fuel consumption, minimizes start-up time, and enhances the durability and efficiency of fuel cell operations by ensuring accurate hydrogen replenishment, reducing corrosion, and meeting emissions requirements.
Implementation Method 1
hydrogen gas is able to diffuse through or cross over the membrane
Implementation Method 2
a flow of air forced through the stack by a compressor
Implementation Method 3
The hydrogen gas is dissociated at the anode catalyst to generate free protons and electrons
Implementation Method 4
A hydrogen fuel cell is an electro-chemical device that includes an anode and a cathode with an electrolyte therebetween
Implementation Method 5
The protons pass through the electrolyte to the cathode. The electrons from the anode cannot pass through the electrolyte
Implementation Method 6
generates an error signal between the estimated concentration and a desired concentration. If the error signal is greater than a second predetermined threshold, the algorithm continues to inject the hydrogen
Data Source
AI summary
A method for determining when to inject hydrogen gas into the anode side of a fuel cell stack associated with a fuel cell vehicle when the vehicle is off. The method includes estimating the concentration of hydrogen gas in the anode side of the fuel cell stack using a gas concentration model and determining if the estimated concentration of hydrogen gas is below a first predetermined threshold. If the estimated hydrogen gas is less than the threshold, then hydrogen gas is injected into the anode side from a hydrogen source. While the hydrogen gas is being injected, the method compares the estimated concentration of the hydrogen gas in the anode side to a desired concentration, and generates an error signal there between. If the error signal is greater than a second predetermined threshold, the algorithm continues to inject the hydrogen into the anode side of the fuel cell stack.