Hybrid Powertrain Power Split Control for Fuel Economy and NOx
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hybrid vehicles face inefficiencies in fuel economy and emissions due to engine idling during creep, suboptimal catalyst temperature operation, and increased NOx emissions when starting the engine at inappropriate times.
Innovation Solution
Implement a control system that uses lookahead information and current state data to dynamically manage power splits between the engine and electric motor, adjust catalyst temperature, and optimize engine operation based on predicted traffic conditions and catalyst status to improve fuel efficiency and reduce emissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the engine is operated during creep idling in heavy traffic, then the vehicle can maintain movement, but fuel economy deteriorates due to wasted fuel consumption
Solution Approach 1:
The control system performs preliminary action by predicting future traffic conditions and catalyst temperature trends using lookahead information. Based on these predictions, the system proactively adjusts the power split between engine and electric motor before entering inefficient operating conditions, thereby avoiding creep idling and maintaining optimal fuel economy.
Solution Approach 2:
The system dynamically adjusts the power split between the engine and electric motor based on real-time traffic conditions, vehicle speed, and predicted future states. This dynamic control allows the vehicle to switch between engine-only, motor-only, and hybrid operation modes optimally, eliminating prolonged engine idling during heavy traffic while maintaining required vehicle performance.
2Object-generated harmful factors
If the engine is operated when catalyst temperature is too low or too high, then the vehicle can be driven, but emissions efficiency deteriorates due to reduced SCR system performance
Solution Approach 1:
The control system uses lookahead information to predict future catalyst temperature trends and traffic conditions. When predictions indicate that catalyst temperature may fall outside the optimal range, the system proactively adjusts the power split to maintain temperature within optimal bounds, preventing inefficient SCR operation and associated high emissions.
Solution Approach 2:
The system continuously monitors actual catalyst temperature and compares it with predicted temperature trends and optimal operating ranges. This feedback mechanism allows the control system to make real-time adjustments to the power split, ensuring the catalyst operates within its optimal temperature window for maximum emissions reduction efficiency.
3Ease of operation
If the engine is turned on while the vehicle is stopped, then the vehicle can be ready for acceleration, but emissions increase due to prolonged engine running to warm up the catalyst
Solution Approach 1:
The control system performs preliminary assessment of traffic conditions and catalyst temperature trends using lookahead information before deciding whether to start the engine. When the vehicle is stopped, the system predicts whether near-future conditions will require engine operation, allowing it to keep the engine off during stops unless absolutely necessary, thereby minimizing warm-up emissions while maintaining vehicle readiness.
Solution Approach 2:
The system changes the operational parameters of the hybrid powertrain by dynamically adjusting the power split between engine and electric motor. During vehicle stops, the system can maintain electric motor operation or reduce engine load, changing the operating state to avoid prolonged engine running and associated emissions, while still ensuring adequate power availability for upcoming acceleration demands.
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
Enhances fuel economy and reduces emissions by efficiently switching between engine and electric motor operation, maintaining optimal catalyst temperature, and minimizing NOx emissions through strategic engine control.
Implementation Method 1
reduced into diatomic nitrogen and water with the help of a catalyst, such as ammonia
Data Source
AI summary
Methods and systems for improving fuel economy and reducing emissions of a vehicle with an electric motor, an engine and an energy storage device are disclosed. The methods and systems involve obtaining lookahead information and current state information, wherein the lookahead information includes a predicted vehicle speed, and the current state information includes a current state of charge (SOC) for the energy storage device coupled to the electric motor; and determining, based on the lookahead information and the current state information, a target power split between the energy storage device and the engine.