Hybrid Engine Stop-Start Control via Temperature and Route Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In hybrid vehicle architectures, frequent engine start/stop cycles due to cold engine warm-up inefficiencies and inadequate battery charging lead to sub-optimal fuel economy, noise, vibration, and reduced engine life, especially in repetitive routes with varying conditions.
Innovation Solution
An engine stop/start control system with modules that adjust restart frequency and duration based on ambient temperature, engine characteristic temperature, expected charging events, and state-of-charge of the energy storage device, combined with route optimization to minimize engine usage and ensure sufficient battery charging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the engine is frequently started and stopped to optimize fuel economy, then fuel consumption is reduced, but engine hardware life expectancy decreases and noise and vibration increase
Solution Approach 1:
The system performs preliminary warm-up of the engine before it is actually needed for propulsion. The controller monitors engine temperature and, when ambient temperature is low, operates the engine in a warm-up mode before normal operation is required. This preliminary action ensures the engine is already warm when needed, eliminating the need for frequent warm-up cycles that would otherwise reduce engine life and increase noise.
2Reliability
If the engine is kept running to maintain optimal temperature, then warm-up inefficiencies are reduced, but fuel consumption increases
Solution Approach 1:
Instead of keeping the engine continuously running, the system uses periodic action by operating the engine in short, controlled intervals. The controller monitors ambient temperature and engine temperature, and only operates the engine periodically when warm-up is actually needed based on these conditions. This periodic operation maintains engine warmth when necessary while avoiding continuous fuel consumption.
Solution Approach 2:
The system uses the engine's own operation to service its own warm-up needs. When ambient temperature is low, the controller activates the engine specifically for warm-up purposes, and the engine's normal operation subsequently provides the warmth needed. This self-service approach eliminates the need for separate heating systems or continuous operation.
3Quantity of substance
If the engine is restarted frequently to replenish energy storage device, then battery charge is maintained, but noise and vibration increase
Solution Approach 1:
The system performs preliminary engine operation to charge the energy storage device before it is completely depleted. The controller monitors the state of charge of the battery and operates the engine in advance to replenish charge when ambient temperature is low, rather than waiting until the battery is depleted. This preliminary charging action reduces the frequency of subsequent engine starts, thereby reducing noise and vibration.
Data Source
AI summary
The present disclosure provides an engine stop/start control system for a vehicle comprising a first engine restart module configured to set a restart frequency and duration of an engine in response to a sensed ambient temperature, a second engine restart module configured to control the engine in response to a sensed characteristic temperature associated with the engine, a third engine restart module configured to control the engine in response to occurrence or non-occurrence of at least one expected charging event along a predefined route, a fourth engine restart module configured to control the engine in response to a state-of-charge of an energy storage device, and a route optimization module configured to set and adjust a proposed route to a destination that results in reduced engine usage.