Electromagnetic Valve Drive Device Adaptive Dead Time Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel injection valve drive devices experience increased heat generation and loss due to diode heating during synchronous rectification control, as the dead time period set by timers often results in longer off-states for switches, prolonging energy transfer to the output capacitor and limiting loss reduction.
Innovation Solution
An electromagnetic valve drive device with a state detection unit and boosting control unit that dynamically control the switching of MOSFET switches based on voltage thresholds, eliminating the need for a timer to prevent simultaneous switch activation, thereby reducing diode heat generation and improving energy transfer efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a timer-based dead time period is used to prevent simultaneous switch activation, then switch safety is improved, but the off-state duration becomes longer than necessary, increasing diode heat generation and reducing loss reduction effectiveness
Solution Approach 1:
The patent implements a feedback mechanism where the control unit monitors the actual on/off states of the first and second switches in real-time. Based on this feedback, the control unit dynamically adjusts the dead time period, shortening it when switches transition smoothly and lengthening it only when necessary to prevent simultaneous activation. This feedback-based adaptive control resolves the contradiction by maintaining switch safety while minimizing unnecessary off-state duration and associated diode losses.
Solution Approach 2:
The patent transitions from a static, fixed dead time period to a dynamic, variable dead time period that adapts to actual switch behavior. The control unit adjusts the dead time duration based on real-time switch state detection, making the system flexible and responsive. This dynamic approach allows the system to maintain reliability while minimizing energy losses compared to a fixed conservative dead time setting.
2Reliability
If the dead time period is extended to ensure safety against simultaneous switch activation, then switch protection is improved, but the energy transfer efficiency deteriorates due to prolonged diode conduction
Solution Approach 1:
The control unit uses feedback from switch state detection to dynamically adjust the dead time period. When switch transitions are smooth and predictable, the dead time is minimized to maintain high energy transfer efficiency. When detection indicates potential simultaneous activation risk, the dead time is extended only to the necessary minimum for protection. This feedback-driven adaptive control resolves the contradiction between switch protection and energy transfer efficiency.
Solution Approach 2:
The patent changes the dead time parameter from a fixed value to a variable value that adapts to operating conditions. The control unit modifies the dead time duration based on real-time switch state feedback, optimizing the balance between protection and efficiency. This parameter change allows the system to maintain high productivity while ensuring adequate switch protection when needed.
3Loss of energy
If synchronous rectification control is implemented to reduce diode current, then diode loss reduction is improved, but the complexity of switch coordination increases due to the need for precise dead time management
Solution Approach 1:
The patent uses feedback from state detection units monitoring switch states to simplify the control logic for synchronous rectification. Instead of requiring complex predetermined timing sequences, the control unit responds to actual switch state feedback, automatically managing dead time and switch coordination. This feedback mechanism reduces control complexity while maintaining the energy loss reduction benefits of synchronous rectification.
Solution Approach 2:
The control system performs self-adjustment of dead time and switch coordination based on real-time state detection feedback. The state detection units provide information about actual switch states, and the control unit autonomously manages the coordination without requiring external complex timing control. This self-service approach reduces the overall system complexity while achieving effective synchronous rectification and diode loss reduction.
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 configuration reduces diode heat generation and enhances charging efficiency to the output capacitor, improving the boost recovery capability and shortening the time to raise the boosted voltage, thus enhancing the performance of the fuel injection valve drive device.
Implementation Method 1
a boost circuit configured to be capable of executing a boosting operation of boosting an input voltage, by accumulating energy in an inductor when a first switch is in an on-state and a second switch is in an off-state, and by supplying the energy accumulated in the inductor to an output capacitor when the first switch is in the off-state and the second switch is in the on-state
Implementation Method 2
The boost circuit is configured to include an inductor, a first switch, a second switch, a diode, and an output capacitor. More specifically, one end of the inductor is connected to a battery power supply, and the other end thereof is connected to an anode of the diode
Data Source
AI summary
An electromagnetic valve drive device includes: a state detection unit configured to detect an on-state or an off-state of a first switch and a second switch forming a boosting circuit; a boosting control unit configured to control a boosting operation, by performing a synchronous rectification control on switching of the first switch and the second switch, depending on the state of the first switch or the second switch detected by the state detection unit; and a drive circuit configured to drive an electromagnetic valve by supplying a voltage boosted by the boosting operation to the electromagnetic valve.