IMPEDANCE SENSING SYSTEMS AND METHODS FOR USE IN MEASURING CONSTITUENTS IN SOLID AND FLUID OBJECTS

• US 20110068807A1
• Filed: 09/22/2010
• Published: 03/24/2011
• Est. Priority Date: 09/22/2009
• Status: Active Grant

• Current Assignee: ADEM, ADEM LLC
• Original Assignee: ADEM
• Inventors: Kesil, Boris, Nikolenko, Yury
• Granted Patent: US 8,547,110 B2
• Time in Patent Office: Days
• US Class Current: 324/633
• CPC Class Codes: G01N 27/023 where the material is placed in the field of a coil

Abstract

Devices and methods of the invention can be used in many industries, including: utilities, agriculture, food, textile, pharmaceutical, photovoltaic and semiconductor, medical devices, chemical and petro-chemical, material science, and defense, where monitoring and/or analysis of various properties of materials are desired.

Claims

1. A resonance type impedance sensor which is a multicoil open-core or air-core inductor, said sensor comprising at least two coils, one coil being an excitation coil connectable to at least one alternating current source with frequency sweep, another coil being a sensing coil connectable to at least one data processing system, wherein upon electrical connection to said current source, said excitation coil propagates an energy to said sensing coil, which generates a probing electromagnetic field, and wherein L C R parameters of said sensing coil are capable of providing resonance conditions for measuring of object under test impedance at predetermined frequency.

2. The sensor of claim 1, further comprising said at least one alternating current source with frequency sweep electrically connected to said at least one excitation coil.

3. The sensor of claim 2, further comprising said at least one data processing system in communication with said at least one sensing coil, wherein L C R parameters of said sensing coil provides resonance conditions for measuring of object under test impedance at predetermined frequency.

4. An impedance sensing system for non-contact and non-invasive measuring and analyzing of targeted chemical and physical properties of gaseous, fluid and solid objects comprising:

(A) at least one resonance type impedance sensor of claim 1;

(B) at least one alternating current source with frequency sweep electrically connected to said at least one excitation coil;

(C) said at least one data processing system in communication with said at least one sensing coil, wherein L C R parameters of said sensing coil provides resonance conditions for measuring of object under test impedance at predetermined frequency; and

(D) a control system in communication with said alternating current source and said data processing system.

5. The impedance sensing system of claim 4, further comprising a fixture to provide object under test placement in close proximity to said sensor(s), so that electromagnetic field induced by said sensing coil(s) can penetrate into said object under test.

7. The method of claim 6, wherein said sensor is the sensor of claim 1.

8. The sensor of claim 3, wherein said data processing system has high impedance input.

9. The sensor of claim 8, wherein said impedance input is greater than 10 MΩ

.

10. The sensor of claim 2, wherein said alternating current source has an adjustable current output.

11. The sensor of claim 1, wherein said sensor is configured as a cylindrical multicoil inductor.

12. The sensor of claim 11, wherein said cylindrical multicoil inductor has a ferromagnetic open core.

13. The sensor of claim 12, wherein said ferromagnetic core is configured as a half pot core.

14. The sensor of claim 12, wherein said cylindrical multicoil inductor has an adjustable ferromagnetic core.

15. The sensor of claim 1, further comprising a support element, wherein said coils are mounted on said support element.

16. The sensor of claim 15, wherein said multicoil inductor is planar.

17. The sensor of claim 15, wherein said support element is a PCB type or flexible support element.

18. The sensor of claim 11, further comprising a support element said coils configured as multicoil inductor being mounted on said support element.

19. The sensor of claim 18, wherein said support element has low coefficient of electrical permittivity.

20. The sensor of claim 19, wherein said support element comprises fluorinated polymer in contact with said mounted multicoil inductor.

21. The sensor of claim 11, further comprising means for adjusting said sensor'"'"'s operating frequency.

22. The sensor of claim 21, wherein said means for adjusting are an adjustable inter-turn step.

23. The sensing system of claim 4, further comprising a vessel for containing of said gaseous, liquid or bulk material object under test.

24. The sensing system of claim 23, wherein said at least one sensor is configured to encompass said vessel, said sensor being configured as a cylindrical multicoil inductor.

25. The sensing system of claim 23, wherein said at least one sensor is mounted on the external or internal wall of said vessel.

26. The sensing system of claim 24 or 25, which comprises a section of pipe, said sensor(s) being installed on said section of pipe.

27. The sensing system of claim 24 or 25, further comprising at least one bypass tubing or a group of channels, said sensor(s) being installed on said at least one bypass tubing or a group of channels

28. The sensing system of claim 4, further comprising means for measuring environmental conditions outside of test object to provide reference information usable to compensate measurement error.

29. The sensing system of claim 28, wherein said means for measuring environmental conditions comprise at least one additional impedance sensor.

30. The method of claim 7, further comprising monitoring of time-related changes in impedance and correlating said chemical or physical properties of said object under test to said time-related changes in impedance.

31. The sensor of claim 1, further comprising a phase detector in communication with said alternating current source and said data processing system.

32. The method of claim 6, further comprising providing the sensor of claim 23, and measuring amplitude and phase shift at fixed frequency which is near resonance frequency of said sensor.

33. The method of claim 7, further comprising applying additional external influence(s) on said object under test to improve sensitivity of said sensing system.

34. The method of claim 33, wherein said additional external influence(s) is selected from the group consisting of UV, IR, magnetic field, electrostatic field, and acoustics wave (ultra sound).

35. The sensor of claim 1, wherein said sensing coil and said excitation coil are spatially separated from one another.

6. A method of measuring chemical and physical properties of an object by a resonance type impedance sensor, said method comprising:

(A) measuring self-resonance frequency and amplitude of said sensor(s);

(B) placing an object under test comprising at least one analyte;

(C) measuring resonant frequency and amplitude of sensor in the presence of said object;

(D) calculating changes in amplitude and resonant frequency induced by electromagnetic interaction between said sensor and object to determine impedance of said object under test; and

(E) matching said impedance with predetermined calibration data to determine said chemical or physical properties of said object under test.