Capacitor-Based Operating Liquid State Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the aggregate state of aqueous operating liquids in motor vehicle containers, such as water and urea solutions, fail to reliably detect the presence of ice at low temperatures, leading to potential vehicle operation disruptions.
Innovation Solution
A method utilizing a capacitor with electrodes attached to the container wall, applying alternating voltages at specific frequencies to determine impedance and phase angles, which indicate the liquid's state, allowing for the detection of solid, liquid, or mixed states without direct contact with the liquid.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing methods are used to determine the aggregate state of aqueous operating liquid, then the measurement process is simple, but the detection reliability of ice formation is insufficient
Solution Approach 1:
The patent replaces mechanical/probe-based detection methods with an electrical field-based measurement system. A capacitor is used to generate an electrical field that interacts with the operating liquid, allowing non-contact detection of aggregate state through impedance and phase angle measurements, thereby improving reliability without requiring complex mechanical probing systems
Solution Approach 2:
The patent introduces an intermediary measurement approach using a capacitor as a mediator between the detection system and the operating liquid. The capacitor's impedance and phase angle serve as intermediary parameters that reflect the liquid's aggregate state, enabling reliable ice detection without direct contact between sensors and liquid
2Measurement precision
If direct contact measurement methods are used, then the measurement is straightforward, but the system cannot reliably detect mixed states at low temperatures
Solution Approach 1:
The patent replaces direct mechanical contact measurement with electrical field-based measurement using a capacitor. By measuring impedance and phase angle through the electrical field interaction, the system achieves precise detection of mixed states without requiring complex direct contact procedures, maintaining ease of operation while improving precision
Solution Approach 2:
The patent utilizes parameter changes in the electrical field response (impedance and phase angle) to detect changes in the operating liquid's aggregate state. By monitoring these electrical parameters, the system can precisely identify mixed states at low temperatures without complicating the measurement 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
Enables reliable detection of ice formation and mixed states, preventing vehicle operation issues by accurately determining the liquid's state and triggering appropriate alerts or heating actions.
Implementation Method 1
determining and storing a first impedance of the capacitor for the first frequency
Implementation Method 2
determining a first phase angle from the first impedance
Data Source
AI summary
A method for determining an aggregate state of an operating liquid in an operating liquid container for a motor vehicle, which operating liquid container has at least one capacitor fastened to a container wall of the operating liquid container and has a first electrode and a second electrode opposite said first electrode. A first method determines the aggregate state of the operating liquid by means of a frequency-dependent phase profile of the impedance of the at least one capacitor. Another method determines the aggregate state of the operating liquid by means of a frequency-dependent capacitance profile of the at least one capacitor. Further, an operating liquid container is designed for carrying out the methods.