Hybrid Engine Combustion Mode Switching With Electric Torque Balancing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing internal combustion engines face challenges in seamlessly switching between combustion modes, leading to torque fluctuations, unstable combustion, and high emissions, which hinder the adoption of high-efficiency combustion modes in hybrid electric vehicles.
Innovation Solution
A method for hybrid electric vehicles that involves commanding a transition between combustion modes using a stable transition operating point, adjusting parameters like intake pressure, temperature, and exhaust gas recirculation, with the electric machine and battery managing torque to maintain stability and efficiency during the transition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the engine switches between combustion modes to improve fuel efficiency, then overall vehicle efficiency is improved, but torque fluctuations and unstable combustion occur during transition
Solution Approach 1:
The system performs preliminary actions by pre-heating the intake manifold and adjusting engine parameters before the actual combustion mode transition. This preparation ensures that when the transition occurs, the combustion remains stable without fluctuations or misfires, thus maintaining reliability while achieving fuel efficiency improvements.
Solution Approach 2:
The intake manifold heating system acts as an intermediary mechanism that facilitates smooth transition between combustion modes. By controlling the thermal state of the intake manifold, it mediates the transition process to prevent unstable combustion and torque fluctuations, enabling both fuel efficiency improvement and combustion stability.
2Object-generated harmful factors
If the engine transitions between combustion modes to reduce emissions, then CO2 emissions are reduced, but the transition process is slow and may cause complete lack of combustion
Solution Approach 1:
The system performs preliminary heating of the intake manifold and pre-adjustment of combustion parameters before the actual mode transition. This preparation reduces the time required for transition and prevents complete lack of combustion by ensuring conditions are ready in advance, thus achieving both emission reduction and fast transition.
Solution Approach 2:
The system uses feedback control to monitor combustion stability and transition progress in real-time. Based on this feedback, it dynamically adjusts heating rates and parameter changes to optimize transition speed while preventing unstable combustion or complete combustion failure, enabling fast and reliable emission reduction.
3Use of energy by moving object
If the engine operates in alternative combustion modes to improve efficiency, then fuel efficiency is improved, but operational difficulties and unacceptably slow transitions occur
Solution Approach 1:
The system performs preliminary actions by pre-heating the intake manifold and pre-adjusting combustion parameters before transition. This preparation eliminates operational difficulties and ensures smooth, rapid transitions that meet driver expectations, thus maintaining ease of operation while achieving fuel efficiency improvements.
Solution Approach 2:
The system dynamically adjusts heating rates, valve timing, and combustion parameters during the transition process. This dynamic control enables the engine to adapt smoothly to changing operating conditions, eliminating operational difficulties and achieving both fuel efficiency and ease of operation.
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
Enables smooth and efficient switching between combustion modes, maintaining operator demand torque and reducing emissions by ensuring stable combustion and efficient operation in hybrid electric vehicles.
Implementation Method 1
a battery electrically coupled to the EM
Implementation Method 2
When the selected predetermined combustion mode-switching operating point of the ICE produces insufficient torque to prevent ICE speed from decreasing, the EM acts as a motor and drives the ICE
Implementation Method 3
When the selected predetermined combustion mode-switching operating point of the ICE produces torque that would cause ICE speed to increase, the EM acts as a generator and loads the ICE
Implementation Method 4
The ICE undergoes preparation to operate in the new combustion mode during the transition interval
Data Source
AI summary
Vehicle designers are largely walking away from internal-combustion engines to battery and electric motors. Until infrastructure is developed to support total electrification, hybrid-electric vehicles (HEVs) which include both an internal combustion engine and an electric machine are a step toward electrification and higher system fuel efficiency while retaining the expected vehicle range. To obtain even higher system fuel efficiency combustion modes that provide higher efficiency than spark-ignition (SI) operation can be used in HEVs. A problem with such combustion modes is that they cannot be used over as wide an operating range as SI operation and transitions among modes is slow and cumbersome. By having the ICE installed into a HEV be a multi-combustion mode engine and having the EM to coordinate mode switches to be smooth, the high fuel-efficiency of alternative combustion modes can be exploited while providing smooth operation expected by vehicle users.