Fuel Injector Coil Drive Residual Magnetization Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel injectors with magnetic coil drives in internal combustion engines experience variations in injection quantity due to electrical tolerances and residual magnetization, which become significant with shorter injection times and multiple injections, leading to imprecise fuel delivery.
Innovation Solution
A method involving connecting both terminals of the fuel injector to ground to measure the current flow and acquire a time curve of the magnetic coil drive's current strength, allowing for a precise adjustment of the voltage pulse duration based on residual magnetization, ensuring accurate injection quantities during multiple injections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If injection times and electrical/hydraulic separation times are shortened to increase productivity, then the number of injections per cycle increases, but relative injection quantity differences between injectors become significant and harmful
Solution Approach 1:
The patent measures the residual magnetization state of the magnetic coil drive before each injection event. By performing this measurement in advance (during the separation time between injections), the system obtains information about the starting state and can adjust the voltage pulse parameters accordingly, ensuring precise injection quantities even with short injection times and high injection frequencies.
2Manufacturing precision
If voltage pulse duration is increased to compensate for residual magnetization, then injection quantity precision improves, but energy consumption increases
Solution Approach 1:
The patent dynamically adjusts the voltage pulse duration based on the measured residual magnetization state. Instead of using a fixed voltage pulse duration, the control unit modifies the pulse width in real-time according to the actual magnetic state of the coil drive, optimizing both injection precision and energy efficiency by applying energy only when and where needed.
Solution Approach 2:
The system changes the operational parameters (voltage pulse duration) based on the measured state of the system (residual magnetization). By adapting the voltage pulse characteristics to the actual magnetic conditions, the system achieves precise injection control while minimizing unnecessary energy consumption that would occur with fixed or overly conservative pulse durations.
3Ease of operation
If residual magnetization is not considered, then actuation process remains simple, but injection quantity variations occur due to electrical tolerances and magnetic state
Solution Approach 1:
The patent implements a feedback mechanism where the residual magnetization state is measured before each injection event. This measurement feedback allows the control system to adjust the voltage pulse parameters based on the actual magnetic state, compensating for variations caused by electrical tolerances and ensuring consistent injection quantities while maintaining a relatively simple actuation process.
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
This approach enables precise and high-precision actuation of fuel injectors by accounting for residual magnetization, reducing variations in injection quantity and ensuring accurate fuel delivery even during short succession injections without additional energy consumption.
Implementation Method 1
a residual magnetization present in the magnetic coil drive can be present from the preceding injection, which can influence the following injection
Implementation Method 2
acquiring a time curve of the current strength of a current flowing through the magnetic coil drive
Data Source
AI summary
A method for actuating a fuel injector having a magnetic coil drive for an internal combustion engine of a motor vehicle is disclosed. The fuel injector has a first terminal and a second terminal, where the first terminal is connectable via a switch element to ground and the second terminal is connected to ground. The method includes the following: actuating the switch element to connect the first terminal to ground, acquiring a time curve of the current strength of a current flowing through the magnetic coil drive, and applying a voltage pulse to the magnetic coil drive to initiate an opening procedure of the fuel injection. A duration of the voltage pulse is established as a function of the acquired time curve of the current strength. Furthermore, an engine controller and a computer program are described.