Variable Port Fuel Injection Windows for Engine Torque Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing engine systems with both port and direct fuel injection struggle to maintain accurate fuel delivery and air-fuel ratio control when engine torque and air flow change during a cylinder cycle, leading to variations in engine torque and increased emissions.
Innovation Solution
The system employs different duration port fuel injection windows in response to fuel injector pulse widths, allowing for adjustments in fuel injection based on estimated cylinder air charge and torque, ensuring accurate fuel delivery by synchronizing port and direct fuel injection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the engine operates at constant operating conditions with fixed port fuel injection window, then the fuel injection process is simplified, but the engine torque and air-fuel ratio control accuracy deteriorates when speed and torque demand change
Solution Approach 1:
The patent applies dynamics by making the port fuel injection window duration variable rather than fixed. The injection window is dynamically adjusted based on real-time engine operating conditions, specifically transitioning between a first duration when engine torque is below a threshold and a second duration when engine torque exceeds the threshold. This dynamic adaptation allows the system to maintain accurate air-fuel ratio control across varying torque and speed conditions while managing the complexity of the fuel injection process.
2Device complexity
If the port fuel injection window duration is fixed, then the injection timing is simple to control, but the engine torque output and air-fuel ratio response become inaccurate when operating conditions change
Solution Approach 1:
The system implements dynamic control of the port fuel injection window duration based on real-time engine torque conditions. When engine torque is below a threshold, a first injection window duration is used; when torque exceeds the threshold, a second injection window duration is applied. This dynamic adjustment enables the system to optimize engine torque output and air-fuel ratio response across different operating conditions without requiring overly complex control mechanisms.
3Device complexity
If a single port fuel injection window is used throughout the cylinder cycle, then the fuel injection system is simpler, but the ability to compensate for changes in cylinder air charge and torque deteriorates
Solution Approach 1:
The patent implements a dynamic fuel injection system that transitions between different port fuel injection window durations based on engine torque conditions. The system monitors engine torque in real-time and adjusts the injection window duration accordingly, enabling compensation for changes in cylinder air charge and torque throughout the cylinder cycle. This dynamic approach balances system complexity with adaptability, allowing the injection system to respond to varying operating conditions without requiring excessive complexity.
4Measurement precision
If the port fuel injection window is shortened for smaller pulse widths, then the fuel injection can be adjusted multiple times, but the total fuel injection duration and torque output may be reduced
Solution Approach 1:
The system dynamically adjusts the port fuel injection window duration based on engine torque conditions rather than using a fixed duration. When engine torque is below a threshold, a first (shorter) injection window duration is used, allowing multiple adjustments to fuel amount. When engine torque exceeds the threshold, a second (longer) injection window duration is applied, ensuring sufficient total fuel injection duration and torque output. This dynamic adaptation resolves the contradiction between adjustment precision and torque output by selecting the appropriate window duration based on real-time torque conditions.
Data Source
AI summary
Methods and systems for simultaneously operating port fuel injectors and direct fuel injectors of an internal combustion engine are described. In one example, different duration port fuel injection windows are provided to maximize fuel injection amount and improve accuracy of an amount of fuel injected during a cylinder cycle via port and direct fuel injectors.