Method and apparatus for monitoring integrity of wires or electrical cables

• US 6,972,574 B2
• Filed: 11/25/2003
• Issued: 12/06/2005
• Est. Priority Date: 01/31/2001
• Status: Expired due to Fees

• Current Assignee: CM Technologies Corporation
• Original Assignee: CM Technologies Corporation
• Inventors: Allan, Gregory, Alstine, Rollin Van
• Primary Examiner(s): Deb, Anjan
• Assistant Examiner(s): KRAMSKAYA, MARINA
• Application Number:
  US10/720,236
• Publication Number:
  US 20040183544A1
• Time in Patent Office: 742 Days
• Field of Search: 324/533, 324/534, 324522-525, 324527-528
• US Class Current: 324/533
• CPC Class Codes: G01R 31/008 on air- or spacecraft, railway rolling stock or sea-going vessels
• CPC Class Codes: G01R 31/11 using pulse reflection methods
• CPC Class Codes: G01R 31/58 Testing of lines, cables or conductors testing of electric windings G01R31/72

Abstract

An apparatus for monitoring the integrity of a wire is provided, which includes a TDR instrument for generating a pulse waveform for transmission through the wire. The apparatus also includes a function generator for generating an electrical or non-electrical forcing waveform for transmission through the wire. The pulse waveform is transmitted through the wire in combination with the forcing waveform and a detector measures a change in dissipation factor values along the wire.

Claims

1. An apparatus for monitoring integrity of a wire, comprising:

a pulse generator for generating a pulse waveform for transmission through the wire;

a function generator for generating a forcing waveform for transmission through the wire, wherein the pulse waveform is transmitted through the wire in combination with the forcing waveforms; and

a detector adapted to measure the change in dissipation factor values along the wire.

2. An apparatus according to claim 1, further comprising a coupling circuit arranged between the pulse generator and the wire.

3. An apparatus according to claim 2, wherein the coupling circuit comprises a high pass filter to isolate the pulse generator from the forcing waveform.

4. An apparatus according to claim 1, wherein the forcing waveform is at a predetermined frequency in accordance with a type of wire insulation material and/or a type of wire conductor material.

5. An apparatus according to claim 1, further comprising a digital multimeter for measuring a voltage induced in the wire.

6. An apparatus according to claim 1, further comprising an impedance meter for measuring the dissipation factor values of the wire.

7. An apparatus according to claim 1, wherein the function generator sweeps the forcing waveform between a frequency range of ω

_min and ω

_max, where ω

_peak is greater than ω

_min and less than ω

_max.

8. A method for monitoring integrity of a wire, comprising the steps of:

generating a pulse waveform for transmission through the wire;

generating a forcing waveform for transmission through the wire;

transmitting the pulse waveform through the wire in combination with the forcing waveform; and

measuring a change in dissipation factor values along the wire.

9. A method according to claim 8, wherein the forcing waveform is at a predetermined frequency in accordance with a wire insulation material and/or a wire conductor material.

10. A method according to claim 8, further comprising a step of measuring a reflected waveform from the transmitted pulse waveform.

11. A method according to claim 8, further comprising a step of isolating the pulse waveform from the forcing waveform.

12. A method according to claim 8, further comprising a step of sweeping the forcing waveform between a frequency range of ω

_min and ω

_max, where ω

_peak is greater than ω

_min and less than ω

_max.