Fuel Cell Truck Route Planning for ESS-Safe Downhill Braking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel cell powered heavy-duty vehicles face challenges in endurance braking performance during extended downhill driving, as the State of Energy (SoE) of the energy storage system (ESS) may become too high, leading to saturation and potential service brake failure.
Innovation Solution
A computer system for heavy-duty vehicles that identifies potentially problematic downhill portions and evaluates candidate routes to determine the optimal route for safe and efficient endurance braking. This system predicts the SoE of the ESS at the onset of the downhill portion for each candidate route, accounting for fuel cell charging operations, uphill portions, and energy storage capacity, to select a route that allows for safe endurance braking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the vehicle uses regenerative braking during downhill driving, then energy efficiency is improved, but the ESS may become saturated leading to braking failure
Solution Approach 1:
The system performs preliminary identification of downhill portions and prediction of ESS state before the vehicle enters the downhill section. By evaluating candidate routes in advance and selecting the optimal one, the system prevents ESS saturation before it occurs, ensuring reliable braking performance while maximizing energy recovery.
Solution Approach 2:
The system continuously monitors the actual ESS state during downhill driving and compares it with the predicted state. This feedback mechanism allows the system to verify the effectiveness of the selected route and adjust future route selections to optimize both energy efficiency and braking reliability.
2Reliability
If the vehicle selects a route with more uphill portions before downhill, then ESS charge is increased improving braking capacity, but travel time and energy consumption increase
Solution Approach 1:
The system changes the routing parameters by evaluating multiple candidate routes with different uphill portions and selecting the optimal route based on predicted ESS state. This allows the system to achieve sufficient braking capacity without unnecessarily increasing travel time or energy consumption, finding the best balance between the two competing requirements.
Solution Approach 2:
The system performs a comprehensive evaluation of multiple candidate routes with varying uphill portions, considering the predicted ESS state for each. By selecting the optimal route from these candidates, the system achieves sufficient braking capacity preparation without applying excessive uphill portions that would unnecessarily increase travel time and energy consumption.
3Measurement precision
If the vehicle evaluates multiple candidate routes with detailed SoE prediction, then route selection accuracy is improved, but computational complexity increases
Solution Approach 1:
The system extracts only the essential factors needed for route selection, such as uphill portions, fuel cell charging operations, and their impact on ESS state. By focusing on these key elements rather than evaluating all possible route characteristics, the system achieves accurate route selection while reducing computational complexity.
Solution Approach 2:
The system segments the route evaluation process by analyzing candidate routes in discrete steps: identifying uphill portions, predicting fuel cell charging operations, calculating predicted ESS state, and selecting the optimal route. This segmentation makes the computational process more manageable and efficient while maintaining high accuracy.
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
The system effectively improves the endurance braking performance of fuel cell powered heavy-duty vehicles by selecting routes that maintain a safe SoE of the ESS during downhill driving, thereby reducing the risk of service brake failure and enhancing overall vehicle operation safety and efficiency.
Implementation Method 1
A battery powered vehicle may employ an on-board fuel cell system in order to convert hydrogen to electrical power
Implementation Method 2
The electric machines on an electrically powered vehicle can be used for both propulsion and for braking, which is an advantage since at least some of the electrical energy spent on accelerating the vehicle may be recuperated during braking
Data Source
AI summary
A computer system for a heavy-duty vehicle has a fuel-cell system and an electrical energy storage system. The computer system comprises processing circuitry configured to identify a downhill portion of a trip to be undertaken by the heavy-duty vehicle, determine at least two candidate routes leading from a starting location along the trip to an onset of the downhill portion of the trip, predict a state of energy, SoE, of the battery system at the onset of the downhill portion for each candidate route, and select a proposed route out of the candidate routes at least in part based on the predicted SoE for each candidate route and on an estimated amount of energy regenerated by traversing the downhill portion of the trip.