Electrochemical impedance measurement system and method for use thereof
AssigneeImpact Technologies, LLC
InventorsCarl S. Byington, Matthew J. Watson, Ryan C. Brewer
Life of this patent
Estimating the term…
Abstract
Disclosed is a method and apparatus for an electrochemical impedance measurement, and in particular circuitry and components employed for such measurements. The system employs an injected broadband AC signal to produce an associated response signal. The subsequent analysis of injected and response signals, considering both magnitude and phase, gives broadband impedance and therefore fluid characteristic information. An embodiment described is relative to a smart oil sensor system suitable for sensing, analyzing and reporting the condition of oil or other liquids used in equipment and machinery.
Claims22
A method for predicting fluid quality and degradation in a fluid system, comprising:
- injecting a broadband signal for impedance measurement into the fluid, wherein the broadband signal provides an assessment of impedance over a range of frequencies and where the range of frequencies is at least a decade of frequencies;
- measuring a low-powered, broadband, AC impedance for a fluid and generating signals indicative of the impedance;
- conducting an analysis of the measured impedance signals to infer a characteristic of the fluid and its constituent components, wherein the analysis further includes
- assessing the signals indicative of impedance for each decade independently, and
- subsequently re-assembling the signals;
- and
- storing at least one characteristic of the fluid.
A method for predicting fluid quality and degradation in a fluid system, comprising:
- injecting a broadband signal for impedance measurement into the fluid, wherein the broadband signal provides an assessment of impedance over a range of frequencies and where the range of frequencies is at least a decade of frequencies;
- measuring a low-powered, broadband, AC impedance for a the fluid in response to the injected broadband signal and generating output response signals indicative of the measured AC impedance;
- conducting an analysis of the measured impedance signals to infer a characteristic of the fluid and its constituent components, wherein the analysis further comprises,
- windowing a portion of the injected broadband signal and output response signal for a common time interval,
- taking a Fast Fourier Transform of the injected broadband and output response signals, and
- using the Fast Fourier Transforms, locating the peaks in the frequency domain at each of the frequencies of the resultant waveform, wherein phase and magnitude signals of the input and output voltages for the injected broadband and output response signals are then converted into complex values and the impedance of the fluid is calculated;
- and storing at least the impedance of the fluid.
A method for sensing electrochemical impedance of a fluid, comprising:
- injecting an AC broadband, composite interrogation signal consisting of multiple frequencies overlaid upon each other within a composite waveform into the fluid;
- simultaneously measuring both the composite interrogation and fluid response signals to produce a combined response;
- interpreting the combined response in the composite interrogation and response signals to generate the electrochemical impedance of the fluid;
- and
- storing data representing at least the electrochemical impedance of the fluid.
A method for sensing electrochemical impedance of a fluid, comprising:
- injecting an interrogation signal into the fluid, wherein the interrogation signal is a broadband voltage signal comprising a plurality of logarithmically-spaced frequencies, and where at least one interrogation signal is created for each frequency range of interest;
- detecting, as a response signal, a response to the interrogation signal passed through the fluid;
- interpreting a combined response based upon the interrogation and response signal variations to determine the electrochemical impedance;
- and
- storing data representing at least the electrochemical impedance.
Dependencies are inferred from the claim text.