Wireless light switch with energy management control
A wireless light switch harvests energy for ambient environment/space conditions and uses the harvested energy to energize low-power electronics. An exemplary application is for wireless control (ON/OFF or dimming) of light fixtures. The energy harvesting circuitry transduces ambient light to electricity and uses this energy to charge an energy storage device as well as power a wireless transmitter which can be triggered based on user interaction with an ON/OFF or Dim+/Dim− element. The wireless light switch with energy harvesting circuitry is paired with a wireless receiver circuit which can be connected to a light fixture that is to be controlled by the wireless light switch.
1. A wireless light switch for controlling a light fixture, the wireless light switch comprising:
a. an energy harvesting circuit configured to harvest energy from light external to the wireless light switch;
b. an energy storage element coupled to the energy harvesting circuit;
c. a wireless transmitter; and
d. a power and control circuit coupled to the energy harvesting circuit, the energy storage element, and the wireless transmitter, wherein the power and control circuit is configured to provide power to the wireless transmitter and to provide control signaling to the wireless transmitter for controlling the light fixture.
2. The wireless light switch of claim 1 wherein the power and control circuit is further configured to monitor a charge level of the energy storage element.
3. The wireless light switch of claim 2 wherein the power and control circuit is further configured to connect or disconnect the energy harvesting circuit from the energy storage element according to the charge level of the energy storage element.
4. The wireless light switch of claim 2 wherein the power and control circuit is further configured to send a control signal to turn ON the light fixture if the charge level of the energy storage element is below a minimum charge threshold level.
5. The wireless light switch of claim 1 wherein the energy harvesting circuit comprises one or more photovoltaic cells.
6. The wireless light switch of claim 1 wherein the energy storage element comprises a rechargeable battery or a capacitor.
7. The wireless light switch of claim 1 wherein the power and control circuit comprises a power conversion circuit.
8. The wireless light switch of claim 1 wherein the power and control circuit comprises a programmable logic circuit.
9. The wireless light switch of claim 8 wherein the power and control circuit comprises a memory for storing a control algorithm implemented by the programmable logic circuit.
10. The wireless light switch of claim 9 wherein the memory further stores a logic table to be implemented by the control algorithm.
11. The wireless light switch of claim 1 further comprising one or more electrical devices coupled to the power and control circuit.
12. The wireless light switch of claim 11 wherein the one or more electrical devices are each configured to provide data signals to the power and control circuit.
13. The wireless light switch of claim 12 wherein the power and control circuit is configured to provide power to the one or more electrical devices.
14. The wireless light switch of claim 11 wherein each of the one or more electrical devices comprises one of a sensor or a timer.
15. A lighting system comprising:
a. a wireless light switch comprising:
I. an energy harvesting circuit configured to harvest energy from light external to the wireless light switch;
ii. an energy storage element coupled to the energy harvesting circuit;
iii. a wireless transmitter; and
iv. a power and control circuit coupled to the energy harvesting circuit, the energy storage element, and the wireless transmitter, wherein the power and control circuit is configured to provide power to the wireless transmitter and to provide control signals to the wireless transmitter;
b. a light fixture remote from the wireless light switch; and
c. a wireless receiver with control circuit coupled to the wireless light switch and the light fixture, wherein the wireless receiver with control circuit is configured to receive the control signals transmitted from the wireless light switch and to control the light fixture according to the received control signals.
16. The lighting system of claim 15 wherein the power and control circuit is further configured to monitor a charge level of the energy storage element.
17. The lighting system of claim 16 wherein the power and control circuit is further configured to connect or disconnect the energy harvesting circuit from the energy storage element according to the charge level of the energy storage element.
18. The lighting system of claim 16 wherein the power and control circuit is further configured to send a control signal to turn ON the light fixture if the charge level of the energy storage element is below a minimum charge threshold level.
19. The lighting system of claim 15 wherein the energy harvesting circuit comprises one or more photovoltaic cells.
20. The lighting system of claim 15 wherein the energy storage element comprises a rechargeable battery or a capacitor.
21. The lighting system of claim 15 wherein the power and control circuit comprises a power conversion circuit.
22. The lighting system of claim 15 wherein the power and control circuit comprises a programmable logic circuit.
23. The lighting system of claim 22 wherein the power and control circuit comprises a memory for storing a control algorithm implemented by the programmable logic circuit.
24. The lighting system of claim 23 wherein the memory further stores a logic table to be implemented by the control algorithm.
25. The lighting system of claim 15 further comprising one or more electrical devices coupled to the power and control circuit.
26. The lighting system of claim 25 wherein the one or more electrical devices are each configured to provide data signals to the power and control circuit.
27. The lighting system of claim 26 wherein the power and control circuit is configured to provide power to the one or more electrical devices.
28. The lighting system of claim 25 wherein each of the one or more electrical devices comprises one of a sensor or a timer.