Fuel Cell Stack Temperature Control Using Weighted Deviation Signals

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing fuel cell systems with multiple stacks face inefficiencies due to averaging process parameter values, leading to suboptimal operation and stability issues, as they do not account for varying conditions across individual stacks.

Innovation Solution

A control method that calculates a weighted average of process parameter deviations based on specific weights assigned to each stack's deviation, considering the operating point and load conditions, to generate a control command for central conditioning devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If average value control is used for multiple fuel cell stacks, then device complexity is reduced, but operational stability deteriorates due to not accounting for individual stack variations

Engineering Contradiction:
Improvecontrol system complexityVSAvoidoperational stability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent assigns different weights to different fuel cell stacks based on their individual characteristics and operating conditions. This allows each stack to be controlled with appropriate local attention, considering its specific state rather than treating all stacks uniformly. The weighting mechanism enables differentiated control strategies for each stack while maintaining a unified control architecture.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The control system dynamically adjusts weights for each fuel cell stack based on real-time operating conditions and deviations from target values. This dynamic weighting allows the system to adapt to changing conditions and prioritize control actions for stacks that need it most, improving overall system stability without requiring complex individual control loops for each stack.

Inventive Principle:
Principle #15Dynamics

2Reliability

If worst-case scenario control is always considered, then operational stability is ensured, but system efficiency deteriorates due to overly conservative control

Engineering Contradiction:
Improveoperational stabilityVSAvoidsystem efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

Instead of always applying worst-case scenario control to all stacks, the patent applies control actions selectively based on weighted deviations. The weighting mechanism allows the system to focus control efforts on stacks with significant deviations while applying more lenient control to stacks operating near target values, avoiding unnecessary conservative actions that would reduce efficiency.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The control system changes the weighting parameters dynamically based on operating conditions and deviation magnitudes. This allows the system to transition between more aggressive control (when deviations are large) and more conservative control (when deviations are small), optimizing the balance between stability and efficiency rather than maintaining a fixed worst-case approach.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4591374B1Inspection method for inspecting at least one central temperature-control device of a fuel cell system
Publication Date: 2025.11.05 AVL LIST GMBH
  • EP4591374B1 patent drawingFigure 1
  • EP4591374B1 patent drawingFigure 2
  • EP4591374B1 patent drawingFigure 3

AI summary

The invention relates to an inspection method for inspecting at least one central temperature-control device (160) for controlling the temperature of a media flow to at least two fuel cell stacks (110) of a fuel cell system (100), having the following steps: - specifying a process parameter target value (PPS), - detecting process parameter actual values (PPI) of the at least two fuel cell stacks (110), - determining process parameter deviations (PPA) as a difference between each detected process parameter actual value (PPI) and a specified process parameter target value (PPS), - specifying weighting factors (G) for the determined process parameter deviations (PPA), - generating a process parameter sum (PPT) on the basis of the process parameter deviations (PPA) and the weighting factors (G) specified for same, and - outputting a control specification (SV) to the at least one central temperature-control device (160) on the basis of the generated process parameter sum (PPT).