Voltage-current phase-based method for linear and rotary transformer systems, and associated systems and methods
A representative phase-shift based method for using a transformer system to detect movement of an object, and associated systems and methods are disclosed. A representative transformer system detects movement of an object and includes an excitation coil configured to receive an excitation coil input signal that results from an input sinusoidal signal. The transformer further includes first and second sensing coils, and a core configured to be operatively coupled to the object. The core moves relative to the first and second sensing coils when the object moves. First and second impedance loads are connected to the first and second sensing coils, respectively. The two impedance loads have different phase-shifting characteristics. A phase-shift sensing circuit determines a phase-shift between the excitation coil input signal and the input sinusoidal signal that is correlated with a position of the core relative to the first and second sensing coils.
1. A system configured to detect movement of an object, comprising:
a transformer circuit including:
an excitation signaling component configured to receive an excitation signal that corresponds to a periodic signal;
first and second signaling components;
a core configured to move relative to the first and second signaling components according to the movement of the object, wherein the core is configured to wirelessly couple the excitation signaling component to the first signaling component, the second signaling component, or a combination thereof based on a position of the core relative to the first and second signaling components;
first and second loads connected to the first and second signaling components, respectively, wherein the first load is different from the second load; and
a sensing circuit configured to determine a difference between the excitation signal and the periodic signal, the difference corresponding to the position of the core.
2. The system of claim 1 , further comprising a sensing resistor configured to (1) receive the periodic signal and (2) provide the excitation coil input signal to the excitation signaling component, the sensing circuit further configured to determine the difference across the sensing resistor.
3. The system of claim 2 , wherein the sensing circuit further includes:
a first comparator configured to generate a first digital signal based on comparing the excitation coil input signal and the input sinusoidal signal; and
a second comparator configured to generate a second digital signal based on the periodic signal,
wherein the sensing circuit is configured to determine the position of the core based on an offset between the first and second digital signals.
4. The system of claim 1 , wherein the first and second impedance loads have different capacitances that correspond to the different phase-shifting characteristic.
5. The system of claim 1 , wherein the first and second impedance loads have different resistances in addition to the different phase-shifting characteristic.
6. The system of claim 1 , wherein the sensing circuit is located farther away from the object that the first and second impedance loads.
7. The system of claim 1 , further comprising first and second wires connecting the sensing circuit with the transformer system, the sensing circuit being located remote from the transformer system.
8. The system of claim 1 , wherein the transformer system is a linear transformer system.
9. The system of claim 1 , wherein the transformer system is a rotary transformer system.
10. The system of claim 1 , wherein the object is a movable component on a flight vehicle.
11. A transformer circuit configured to identify a position of an object or a change in the position, the transformer circuit comprising:
an excitation signaling component configured to receive an excitation signal;
a first signaling component including a first load;
a second signaling component located away from the first signaling component and including a second load different from the first load; and
a core (1) located between the excitation signaling component and the first and second signaling components and (2) configured to move relative to the first and second signaling components according to the position of the object thereby inductively coupling the excitation interface to the first signaling component, the second signaling component, or a combination thereof.
12. The transformer circuit of claim 11 , wherein the first and second loads have different capacitances that correspond to different phase-shifting characteristic.
13. The transformer circuit of claim 12 , wherein the first and second loads have different resistances in addition to the different phase-shifting characteristic.
14. The transformer circuit of claim 12 , wherein the core is configured to move linearly relative to the first and second signaling components.
15. The transformer circuit of claim 12 , wherein the core is configured to move rotationally relative to the first and second signaling components.
16. A method of identifying a position of an object or a change in the position, the method comprising:
providing a periodic signal;
inductively communicating the periodic signal to at least one of a first load and a second load using a core configured to move according to a movement of the object, wherein the core is configured to move along a path associated with locations of the first and second loads;
detecting a loaded signal that represents the periodic signal having been changed according to the inductive coupling between the excitation signaling component and the at least one of the first and second loads according to a location of the core along the path; and
determining the position of the core based on a difference between the periodic signal and the loaded signal.
17. The method of claim 16 , further comprising:
generating a first digital signal based on comparing the periodic signal and the loaded signal; and
generating a second digital signal based on the periodic signal, and
wherein the determined position of the core is based at least in part on a delay between the first and second digital signals.
18. The method of claim 17 , wherein determining the position includes comparing corresponding edges of the first and second digital signals to determine the delay.
19. The method of claim 16 , wherein:
the first and second loads correspond to ends of the path for the core;
the first and second loads include different phase-shifting components; and
the position of the core is determined based on a phase shift or a magnitude of a phase shifted component in the loaded signal in comparison to the periodic signal.
20. The method of claim 19 , wherein:
the first and second loads include different capacitances; and
the position of the core is determined based on the phase shift or the magnitude of the phase shifted component that represents distances from the first and second loads along the path and corresponding influences from the different capacitances.