Fuel Cell Regenerative Braking Control Using COD Heater Power Limits

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing regenerative braking control systems for fuel cell vehicles struggle to accurately determine the optimal consumption of regenerative braking energy, leading to inefficient energy use and instability due to the inability to adjust consumption effectively and consider the power limitations of devices like the COD heater.

Innovation Solution

A regenerative braking control apparatus and method that includes a processor to calculate a reference state-of-charge (SOC) based on an expected driving route, determine the limit power of the COD heater based on the operating state of the cooling device, and calculate the consumable power of the COD heater, allowing for precise control of regenerative braking energy consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If regenerative braking energy is consumed by the COD heater, then energy efficiency is improved, but battery overcharging risk increases

Engineering Contradiction:

Improveenergy efficiencyVSAvoidbattery overcharging prevention

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The control apparatus continuously monitors battery SOC (state of charge) and adjusts the COD heater power consumption accordingly. When battery SOC reaches a reference level, the system automatically reduces or stops regenerative braking energy consumption by the COD heater, preventing battery overcharging while maximizing energy efficiency when the battery needs charging.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system dynamically adjusts the power consumption of the COD heater based on real-time battery SOC conditions and driving patterns. The control apparatus varies the heater power demand to match battery charging capacity, enabling flexible energy management that adapts to changing operational conditions rather than using a fixed consumption rate.

Inventive Principle:

Principle #15Dynamics

2Use of energy by moving object

If the COD heater power consumption is increased to consume more regenerative braking energy, then energy efficiency improves, but system stability deteriorates due to power limitation violations

Engineering Contradiction:

Improveenergy efficiencyVSAvoidsystem stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The control apparatus calculates and adjusts the COD heater power consumption parameter based on the power limitation information. When the calculated power demand exceeds the limitation, the system modifies the power parameter to match the limitation, ensuring stable operation. This dynamic parameter adjustment maintains energy efficiency while respecting system power constraints.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If the consumption of regenerative braking energy is fixed, then control simplicity is maintained, but adaptability to different driving conditions deteriorates

Engineering Contradiction:

Improvecontrol simplicityVSAvoidadaptability to driving conditions

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The control apparatus pre-calculates reference SOC values based on expected driving patterns and route information before actual driving occurs. This preliminary calculation enables the system to adapt to different driving conditions without complex real-time adjustments, maintaining control simplicity while improving adaptability through advance planning.

Inventive Principle:

Principle #10Preliminary action

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 solution enables more accurate estimation and control of regenerative braking energy, preventing overcharging of the battery, improving stability by considering power limitations, and allowing flexible adjustment of energy consumption based on dynamic driving conditions.

Implementation Method 1

The fuel cell generates electricity by using a chemical reaction between hydrogen and oxygen

Methodology Applied

Scientific EffectChemical reaction:

Implementation Method 2

a cathode oxygen depletion (COD) heater that removes gas remaining in the fuel cell stack

Methodology Applied

Scientific EffectHeating: Heating

Implementation Method 3

calculates limit power of the COD heater based on an operating state of a cooling device for cooling the COD heater

Methodology Applied

Scientific EffectHeat transfer: Heat Exchanger

Data Source

PatentUS12337725B2Apparatus and method for controlling regeneration of fuel cell vehicle

Publication Date: 2025.06.24 HYUNDAI MOTOR CO LTD

AI summary

In an embodiment a regenerative braking control apparatus includes a fuel cell stack configured to provide energy to a driving motor of the vehicle, a cathode oxygen depletion (COD) heater configured to remove gas remaining in the fuel cell stack, a high voltage battery configured to supply power to the driving motor or to be charged by using power generated by the driving motor through regenerative braking and a processor configured to calculate a reference state-of-charge (SOC) based on an expected driving route, to calculate a limit power for the COD heater based on an operating state of a cooling device for cooling the COD heater when a SOC of the high voltage battery is greater than or equal to the reference SOC and to calculate consumable power of the COD heater based on the limit power of the COD heater.