Linear solid-state lighting with bidirectional circuits
A linear light-emitting diode (LED) lamp comprising a normally-operated portion and an emergency-operated portion is used to replace a luminaire operated only in a normal mode with alternate-current (AC) mains. The normally-operated portion comprises a fly-back converter whereas the emergency-operated portion comprises a rechargeable battery, a bidirectional circuit, a boost converter, a self-diagnostic circuit, and a control circuit. The linear LED lamp can auto-switch from the normal mode to an emergency mode according to availability of the AC mains and whether a rechargeable battery test is initiated. The bidirectional circuit is configured to convey a forward electric current and a reverse electric current to and from the rechargeable battery, respectively. The self-diagnostic circuit is configured to provide multiple sequences and to auto-evaluate battery performance according to the multiple sequences. During an auto-evaluation period, a terminal voltage on the rechargeable battery is examined with test results displayed in a status indicator.
1. A linear light-emitting diode (LED) lamp, comprising:
at least two electrical conductors configured to couple to a line voltage from alternate-current (AC) mains;
one or more LED arrays with a forward voltage across the one or more LED arrays;
a rechargeable battery with a terminal voltage across thereon;
at least one full-wave rectifier coupled to the at least two electrical conductors and configured to convert the line voltage into a primary direct-current (DC) voltage;
a bidirectional circuit comprising one or more electronic switches and configured to control a forward electric current and a reverse electric current to and from the rechargeable battery, respectively;
a boost converter circuit comprising a boost control circuit, one or more switches, an inductor, and at least one capacitor, the boost converter circuit configured to cut off a constant source of power from the rechargeable battery into controllable increments of energy pulses, followed by the at least one capacitor rebuilding the controllable increments of energy pulses back into a regulated output voltage greater than the forward voltage with a first LED driving current;
a fly-back converter circuit comprising a transformer, the fly-back converter circuit configured to generate a second LED driving current to power up the one or more LED arrays at a full power when the line voltage is available;
a primary control circuit configured to control the bidirectional circuit and to enable the boost converter circuit to operate when a rechargeable battery test is performed; and
a major power source configured to couple to the at least one full-wave rectifier and to provide a DC power to the bidirectional circuit and the rechargeable battery.
2. The linear light-emitting diode (LED) lamp of claim 1 , wherein the one or more electronic switches comprise a first electronic switch and a second electronic switch, and wherein the first electronic switch is configured to receive a first set of one or more signals from the primary control circuit to regulate the forward electric current to flow into the rechargeable battery via the second electronic switch.
3. The linear light-emitting diode (LED) lamp of claim 1 , wherein the bidirectional circuit further comprises a first control circuit configured to regulate the forward electric current to flow into the rechargeable battery.
4. The linear light-emitting diode (LED) lamp of claim 3 , wherein the one or more electronic switches comprise a first set of one or more electronic switches and a second set of one or more electronic switches, and wherein the forward electric current is allowed to flow into the rechargeable battery via the first set of one or more electronic switches.
5. The linear light-emitting diode (LED) lamp of claim 4 , wherein the second set of one or more electronic switches are configured to receive a second set of one or more signals from the primary control circuit and to allow the reverse electric current to flow out of the rechargeable battery.
6. The linear light-emitting diode (LED) lamp of claim 5 , wherein the second set of one or more electronic switches comprise at least one transistor circuit configured to activate the boost converter circuit.
7. The linear light-emitting diode (LED) lamp of claim 1 , wherein the primary control circuit comprises a second control circuit comprising a third electronic switch and a fourth electronic switch, and wherein the third electronic switch and the fourth electronic switch are configured to control whether the second LED driving current is supplied into the one or more LED arrays or not.
8. The linear light-emitting diode (LED) lamp of claim 7 , wherein the third electronic switch is configured to turn on the fourth electronic switch, thereby allowing the second LED driving current to flow into the one or more LED arrays.
9. The linear light-emitting diode (LED) lamp of claim 8 , wherein the fourth electronic switch comprises at least one metal-oxide-semiconductor field-effect transistor (MOSFET) configured to couple between the fly-back converter circuit and the one or more LED arrays and to controllably relay the second LED driving current to reach the one or more LED arrays.
10. The linear light-emitting diode (LED) lamp of claim 9 , wherein the third electronic switch comprises at least one bipolar junction transistor (BJT) coupled to the at least one MOSFET and configured to receive a logic high level or a logic low level to respectively turn the at least one MOSFET on or off, and wherein, when the at least one MOSFET is turned off, the second LED driving current is interrupted with an output of the fly-back converter circuit open-circuited.
11. The linear light-emitting diode (LED) lamp of claim 7 , wherein the second control circuit is configured to forbid the second LED driving current to flow into the one or more LED arrays during the rechargeable battery test.
12. The linear light-emitting diode (LED) lamp of claim 7 , wherein the second control circuit further comprises a signaling device configured to enable and disable the fly-back converter circuit.
13. The linear light-emitting diode (LED) lamp of claim 1 , wherein the primary control circuit further comprises a self-diagnostic circuit comprising one or more timers, wherein each of the one or more timers respectively comprises multiple time delays, wherein the multiple time delays respectively further comprise a first time delay and a second time delay, wherein, upon an initiation of each of the one or more timers, the first time delay begins with an input voltage applied on the self-diagnostic circuit, wherein, at an end of the first time delay, an output of the self-diagnostic circuit is activated to reach a logic high level and remains activated so as to enable the boost converter circuit for the second time delay, wherein, at an end of the second time delay, the output of the self-diagnostic circuit is inactivated to drop to a logic low level to disable the boost converter circuit, and wherein a duration over the second time delay is configured to allow the self-diagnostic circuit to perform the rechargeable battery test.
14. The linear light-emitting diode (LED) lamp of claim 13 , wherein the primary control circuit further comprises a test portion configured to examine a fraction of the terminal voltage on the rechargeable battery over a duration of the second time delay when the rechargeable battery test is initiated.
15. The linear light-emitting diode (LED) lamp of claim 1 , wherein the linear LED lamp further comprises a first end and a second end opposite to the first end, wherein the at least one full-wave rectifier further comprises a first full-wave rectifier and a second full-wave rectifier each configured to independently receive the line voltage, wherein either of the first end and the second end comprises at least two electrical conductors, wherein each of the at least two electrical conductors is respectively coupled to the first full-wave rectifier and the second full-wave rectifier, and wherein the second full-wave rectifier is configured to power the major power source at all times.
16. The linear light-emitting diode (LED) lamp of claim 1 , wherein the primary control circuit further comprises at least one status indicator configured to show a result of the rechargeable battery test.
17. The linear light-emitting diode (LED) lamp of claim 1 , wherein the primary control circuit further comprises a test switch configured to manually initiate the rechargeable battery test.
18. The linear light-emitting diode (LED) lamp of claim 17 , wherein the test switch is further configured to manually cause the self-diagnostic circuit to terminate the rechargeable battery test that is in progress.
19. The linear light-emitting diode (LED) lamp of claim 1 , wherein the linear LED lamp further comprises a voltage regulator configured to automatically receive the forward electric current and the reverse electric current to and from the rechargeable battery, respectively, and to adapt either an output voltage from the major power source or the terminal voltage to an operating voltage of the primary control circuit to operate thereof.