Method and system for localization on a DC lighting and power grid

1. A method for locating a luminaire on a DC grid, the DC grid comprising a first DC grid power line, an AC signal generator switchably connected to the first DC grid power line, and a first luminaire in electrical communication with the first DC grid power line, the first luminaire disposed along the first DC grid power line at a first distance from the AC signal generator, the method comprising the steps of:

connecting the AC signal generator to the first DC grid power line;

transmitting, by the AC signal generator, an AC signal along the first DC grid power line;

receiving the AC signal by the first luminaire; and

calculating the first distance between the AC signal generator and the first luminaire, based in part upon the AC signal.

2. The method of claim 1 , where the first DC grid power line is terminated for the AC signal with a resistance approximating a characteristic impedance of the first DC grid power line, the method further comprising the steps of:

recording, by the first luminaire, a first phase of the AC signal at the first luminaire; and

recording, by the AC signal generator, a second phase of the AC signal at the AC signal generator;

wherein the step of calculating the first distance further comprises measuring a difference between the first phase and the second phase.

3. The method of claim 1 , wherein the first DC grid power line is unterminated for the AC signal, the method further comprising the steps of:

setting the frequency of the AC signal such that the AC signal forms a standing wave across the first DC grid power line, the standing wave comprising a maximum amplitude; and

recording, by the first luminaire, a first amplitude of the AC signal at the first luminaire;

wherein the step of calculating the first distance further comprises measuring a difference between the first amplitude and the maximum amplitude.

4. The method of claim 1 , wherein the first DC grid power line is unterminated for the AC signal, the AC signal further comprising an amplitude, the method further comprising the steps of:

sweeping the frequency of the AC signal between a first frequency and a second frequency;

recording, by the first luminaire, a first time corresponding to a time the first luminaire initially detects the AC signal; and

recording, by the first luminaire, a second time corresponding to a time the first luminaire detects the amplitude of the AC signal corresponding to a null amplitude;

wherein the step of calculating the first distance further comprises measuring a difference between the first time and the second time.

5. The method of claim 1 , wherein the AC signal comprises a pulse signal, the first DC grid power line is unterminated for the AC signal, the method further comprising the steps of:

recording, by the first luminaire, a first time corresponding to a time the first luminaire initially detects the pulse signal; and

recording, by the first luminaire, a second time corresponding to a time the first luminaire initially detects a reflection of the pulse signal;

wherein the step of calculating the first distance further comprises measuring a difference between the first time and the second time.

6. The method of claim 1 , wherein the DC grid further comprises a second DC grid power line, the AC signal generator switchably connected to the second DC grid power line, and a second luminaire in electrical communication with the second DC grid power line, the second luminaire disposed along the second DC grid power line at a second distance from the AC signal generator, the method further comprising the steps of:

connecting the AC signal generator to the second DC grid power line;

transmitting, by the AC signal generator, an AC signal along the second DC grid power line;

receiving the AC signal by the second luminaire; and

calculating the second distance between the AC signal generator and the second luminaire, based in part upon the AC signal.

7. The method of claim 1 , wherein the DC grid further comprises a memory, the method further comprising the steps of:

storing the first distance in the memory; and

communicating the first distance to a DC grid mapper.

8. The method of claim 7 , wherein the step of communicating the first distance to the DC grid mapper further comprises the step of transmitting a wireless signal to the DC grid mapper.

9. The method of claim 7 , wherein the memory is disposed within the first luminaire, the DC grid mapper is in electrical communication with the DC grid, and the step of communicating the first distance to a DC grid mapper further comprises the step of transmitting a communication signal along the first DC grid power line from the first luminaire to the DC grid mapper.

10. The method of claim 1 , further comprising the steps of:

assigning a first identifier to the first luminaire; and

communicating the first identifier between the first luminaire and the AC signal generator.

11. The method of claim 10 , wherein the step of communicating the first identifier further comprises the step of transmitting a wireless signal to the DC grid mapper.

12. The method of claim 10 , wherein the DC grid mapper is in electrical communication with the DC grid, and wherein the step of communicating the first identifier further comprises the step of transmitting a communication signal along the first DC grid power line from DC grid mapper to the first luminaire.

13. The method of claim 1 , wherein the DC grid further comprises an EMerge Alliance Standard-compliant lighting system.

14. The method of claim 1 , further comprising recording a property of said AC signal at said first luminaire, wherein the calculating the first distance is based at least in part on the recorded property of said AC signal at said first luminaire.