Sensor Fault Diagnosis via Electrostatic Leakage Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing physical quantity measurement devices face challenges in fault diagnosis due to individual variations in sensor elements, requiring complex circuits and trimming technologies, which hinder miniaturization and increase costs, and struggle to accurately diagnose faults without affecting the sensor's operation.
Innovation Solution
A physical quantity measurement device incorporating a fault diagnosis circuit with an electrostatic leakage component extraction circuit that utilizes the coupling capacitance between drive and detection electrodes to extract and diagnose faults, allowing for more accurate and simplified fault detection without the need for vibration leakage components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If vibration leakage component is used for fault diagnosis, then fault diagnosis can be performed, but determination accuracy degrades due to individual variation of sensor element
Solution Approach 1:
The invention extracts the electrostatic leakage component specifically from the detection signal using a dedicated extraction circuit. This separates the fault diagnosis function from the main detection function, allowing accurate extraction of the leakage component that is affected by coupling capacitance between drive and detection electrodes, thereby improving determination accuracy while maintaining fault diagnosis capability
Solution Approach 2:
The invention introduces an intermediary electrostatic leakage component that is generated through coupling capacitance between the drive electrode and detection electrode. This intermediary signal serves as a reliable basis for fault diagnosis because its characteristics are determined by the fixed coupling capacitance rather than individual sensor variations, thus resolving the accuracy problem
2Reliability
If trimming technology is used to extract vibration leakage component, then reliable fault diagnosis can be achieved, but device complexity increases
Solution Approach 1:
The invention replaces the mechanical/physical trimming process with an electrical signal processing approach. Instead of physically adjusting or trimming the sensor to extract the leakage component, the system uses an electrostatic leakage component extraction circuit that electronically separates and processes the leakage signal from the detection signal, thereby reducing device complexity while maintaining diagnosis reliability
Solution Approach 2:
The invention uses the electrostatic coupling capacitance between electrodes as an intermediary mechanism to generate a predictable leakage component. This intermediary signal path provides a reliable basis for fault diagnosis without requiring complex trimming circuits or additional hardware, thus achieving reliability with reduced complexity
3Reliability
If synchronous detection circuit is added to extract vibration leakage component, then fault diagnosis can be performed, but chip size grows
Solution Approach 1:
The invention merges the fault diagnosis function with the existing detection signal processing path. The electrostatic leakage component extraction circuit processes the same detection signal that is already being amplified and processed for normal operation, combining multiple functions into a unified signal path. This integration approach enables fault diagnosis without requiring separate dedicated circuits, thereby preventing chip size growth
Solution Approach 2:
The invention extracts the electrostatic leakage component directly from the detection signal using a dedicated extraction circuit that operates within the existing signal processing architecture. This extraction approach obtains the necessary fault diagnosis information from the available detection signal without requiring additional synchronous detection circuits or separate signal paths, thus avoiding increase in chip size
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 enhances fault diagnosis accuracy, reduces circuit complexity, and enables miniaturization by using electrostatic leakage components, improving determination accuracy and reducing temperature variation effects, thus ensuring reliable operation across a broad temperature range.
Implementation Method 1
a sensor element having a drive electrode and a detection electrode, and provided with a coupling capacitance formed between the drive electrode and the detection electrode
Data Source
AI summary
A physical quantity measurement device includes a sensor element having a coupling capacitance formed between a drive electrode and a detection electrode, and a circuit device having a drive circuit adapted to supply a drive signal to the drive electrode, a detection circuit adapted to detect physical quantity information corresponding to a physical quantity based on a detection signal from the detection electrode, and a fault diagnosis circuit, and the fault diagnosis circuit has an electrostatic leakage component extraction circuit adapted to extract an electrostatic leakage component due to the coupling capacitance from one of the detection signal and an amplified signal of the detection signal, and performs a fault diagnosis based on the electrostatic leakage component extracted.