High speed AC input sensor conversion

Patent metadata

Field	Value
Publication number	US-11092464-B2
Application number	US-201916246918-A
Country	US
Kind code	B2
Filing date	Jan 14, 2019
Priority date	Jan 14, 2019
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A system for determining an amplitude of a sinusoidal output waveform from a sensor includes a controller configured to provide a sample signal having a sample frequency that is four times a frequency of a sinusoidal excitation waveform provided to the sensor. The sensor has inductively-coupled primary and secondary windings that produce the sinusoidal output waveform from the secondary winding when the excitation waveform is provided to the primary winding. An analog-to-digital converter measures a first and second voltage of the sensor waveform separated in time by the period of the sample frequency, and the system calculates the amplitude based on the measurements of the first and second voltages.

First claim

The invention claimed is:

1. A system for determining position of a movable component by calculating an amplitude of a sinusoidal output waveform from a sensor, the system comprising a controller configured to:
provide a sample signal having a sample frequency that is four times a frequency of a sinusoidal excitation waveform provided to the sensor, the sensor having:
a primary winding configured to receive the sinusoidal excitation waveform; and
a secondary winding, inductively coupled to the primary winding in such a manner that the inductive coupling changes in response to movement of the movable member, the secondary winding configured to produce the sinusoidal output waveform when the sinusoidal excitation waveform is provided to the primary winding;

measure a first voltage of the sinusoidal output waveform and a second voltage of the sinusoidal output waveform using an analog-to-digital converter (ADC), the second voltage measurement occurring at a time corresponding to a period of the sample frequency following the first voltage measurement;
calculate the amplitude of the sinusoidal output waveform based on the measurements of the first and second voltages; and
determine a position of a movable component based on the amplitude of the sinusoidal output waveform calculated.

2. The system of claim 1 , wherein:
the sensor is a linear variable differential transformer (LVDT); and
the sensor is configured to measure a linear position of a linear component mechanically connected thereto.

3. The system of claim 2 , wherein the amplitude is representative of the linear position.

4. The system of claim 1 , wherein the sensor is a resolver further comprising a tertiary winding, wherein:
the primary winding is rotatable;
the secondary winding is fixed relative to the primary winding;
the tertiary winding is fixed relative to the primary winding and positioned out of phase with respect to the secondary winding; and
the sensor is configured to measure an angular position of a rotatable component mechanically connected thereto.

5. The system of claim 4 , wherein the tertiary winding is positioned π/2 radians out of phase with respect to the secondary winding.

6. The system of claim 4 , wherein the amplitude is representative of the angular position of the rotary component.

7. The system of claim 1 , wherein the excitation frequency is between 400-5,000 Hz.

8. The system of claim 1 , wherein the sinusoidal excitation waveform further comprises a peak amplitude between 5-12 volts.

9. The system of claim 1 , wherein the amplitude is a root-mean-square (RMS) amplitude.

10. The system of claim 1 , further comprising:
an exciter, configured to receive the excitation signal from the controller and to provide to the primary winding the sinusoidal excitation waveform having the excitation frequency;
the sensor; and
the ADC.

11. A method of determining position of a movable component by calculating an amplitude of a sinusoidal output waveform from a sensor, the method comprising:
providing, by a controller, an excitation signal having an excitation frequency to an exciter;
providing, by the controller, a sample signal having a sample frequency that is four times the excitation frequency, to an analog-to-digital converter (ADC),
supplying, by the exciter, a sinusoidal excitation waveform having the excitation frequency to a primary winding, wherein:
the primary winding is inductively coupled to a secondary winding in such a manner that the inductive coupling changes in response to movement of the movable member;
the secondary winding is configured to produce the sinusoidal output waveform when the sinusoidal excitation waveform is supplied to the primary winding; and
the secondary winding is configured to input the sinusoidal output waveform to an ADC;

measuring, by the ADC, a first voltage of the sinusoidal output waveform and a second voltage of the sinusoidal output waveform, the second voltage measurement occurring at a time corresponding to a period of the sample frequency following the first voltage measurement;
calculating, by the controller, the amplitude based on the measurements of the first and second voltage; and
determining, by the controller, a position of a movable component based on the amplitude of the sinusoidal output waveform calculated,
wherein the primary winding and the secondary winding comprise the sensor.

12. The method of claim 11 , wherein:
the sensor is a linear variable differential transformer (LVDT); and
the sensor is configured to measure a linear position of a linear component mechanically connected thereto.

13. The method of claim 12 , wherein the amplitude is representative of the linear position.

14. The method of claim 11 , wherein the sensor is a resolver further comprising a tertiary winding, wherein:
the primary winding is rotatable;
the secondary winding is fixed relative to the primary winding;
the tertiary winding is fixed relative to the primary winding and positioned out of phase with respect to the secondary winding; and
the sensor is configured to measure an angular position of a rotatable component mechanically connected thereto.

15. The method of claim 14 , wherein the tertiary winding is positioned π/2 radians out of phase with respect to the secondary winding.

16. The method of claim 14 , wherein the amplitude is representative of the angular position of the rotary component.

17. The method of claim 11 , wherein the excitation frequency is between 400-5,000 Hz.

18. The method of claim 11 , wherein the excitation frequency is between 2,000-3,500 Hz.

19. The method of claim 11 , wherein the sinusoidal excitation waveform further comprises a peak amplitude between 5-12 volts.

20. The method of claim 11 , wherein the amplitude is a root-mean-square (RMS) amplitude.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Hess Gary L
• Wilson Michael A

Classifications

• G01D5/2291 Primary

  Linear or rotary variable differential transformers (LVDTs/RVDTs) having a single primary coil and two secondary coils · CPC title

• H03M1/485

  for position encoding, e.g. using resolvers or synchros · CPC title

• H01F21/06

  by movement of core or part of core relative to the windings as a whole · CPC title

• G01D5/2073

  by movement of a single coil with respect to two or more coils · CPC title

• G01D5/2046

  by a movable ferromagnetic element, e.g. a core · CPC title