Discharge lamp electronic ballast luminaire and vehicle with same
View Patent ↗Discharge lamp electronic ballast includes DC-DC converter circuit for converting voltage of DC power supply to output DC power, inverter circuit for converting DC power into AC power to supply it to discharge lamp, output feedback control circuit for controlling DC-DC converter circuit, and inverter driving signal generator circuit for controlling inverter circuit. Ballast includes microcomputer having voltage detecting function for detecting voltage value of DC power supply, and ballast temperature detector circuit for detecting temperature of ballast. Microcomputer sets first time based on voltage value of DC power supply and detection result of ballast temperature detector circuit, and reduces power supplied to the discharge lamp if first time elapses from time point when lamp is started, thereby supplying lamp with power for stable operation.
1. A discharge lamp electronic ballast, comprising:
a DC-DC converter circuit configured to convert a voltage of a DC power supply so as to output DC power;
an inverter circuit configured to convert the DC power into AC power to supply the power to a discharge lamp; and
a controller configured to control the DC-DC converter circuit and the inverter circuit,
wherein the controller comprises:
a voltage detector configured to detect a voltage value of the DC power supply or a value corresponding to the voltage value; and
a temperature detector configured to detect a temperature of the ballast or a value corresponding to the temperature of the ballast,
wherein the controller is configured:
during a first time period from a point in time when the discharge lamp is started and a second time period after the first time period, to supply the discharge lamp with power larger than power to be supplied during a stable operation of the discharge lamp;
to supply the discharge lamp with a rated output for a fixed time after the second time period, thereby supplying the discharge lamp with power equal to or larger than a fixed value until a first time elapses from a start of the discharge lamp, the first time including the first time period, the second time period and the fixed time; and
to reduce the power supplied to the discharge lamp when the first time elapses from the start of the discharge lamp, thereby supplying the lamp with power for the stable operation,
wherein the controller is further configured to set the first time based on a detection result of the voltage detector and a detection result of the temperature detector.
2. The discharge lamp electronic ballast of claim 1 , wherein the controller is configured to set a reducing rate and a reduced volume of the power supplied to the discharge lamp after the first time elapses based on the detection result of the voltage detector.
3. The discharge lamp electronic ballast of claim 1 , wherein the controller is configured to set a reducing rate of the power supplied to the discharge lamp after the first time elapses based on the detection result of the temperature detector.
4. The discharge lamp electronic ballast of claim 1 , wherein the controller has reducing rates of the power supplied to the discharge lamp, said reducing rates corresponding to detection results of the voltage detector or detection results of the temperature detector.
5. The discharge lamp electronic ballast of claim 1 , wherein the controller stores a reference curve of power and is configured to set a reduced volume of the power supplied to the discharge lamp based on the curve of power.
6. The discharge lamp electronic ballast of claim 2 , wherein the controller stores a reference curve of power and is configured to set the reduced volume of the power supplied to the discharge lamp based on the curve of power.
7. The discharge lamp electronic ballast of claim 1 , wherein the controller comprises a lower limit for a reduced volume of the power supplied to the discharge lamp, said lower limit corresponding to detection results of the voltage detector or detection results of the temperature detector.
8. The discharge lamp electronic ballast of claim 2 , wherein the controller comprises a lower limit for the reduced volume of the power supplied to the discharge lamp, said lower limit corresponding to detection results of the voltage detector or detection results of the temperature detector.
9. A luminaire, comprising a discharge lamp electronic ballast, wherein the discharge lamp electronic ballast comprises:
a DC-DC converter circuit configured to convert a voltage of a DC power supply so as to output DC power;
an inverter circuit configured to convert the DC power into AC power to supply the power to a discharge lamp; and
a controller configured to control the DC-DC converter circuit and the inverter circuit,
wherein the controller comprises:
a voltage detector configured to detect a voltage value of the DC power supply or a value corresponding to the voltage value; and
a temperature detector configured to detect a temperature of the ballast or a value corresponding to the temperature of the ballast,
wherein the controller is configured:
during a first time period from a point in time when the discharge lamp is started and a second time period after the first time period, to supply the discharge lamp with power larger than power to be supplied during a stable operation of the discharge lamp;
to supply the discharge lamp with a rated output for a fixed time after the second time period, thereby supplying the discharge lamp with power equal to or larger than a fixed value until a first time elapses from a start of the discharge lamp, the first time including the first time period, the second time period and the fixed time; and
to reduce the power supplied to the discharge lamp when the first time elapses from the start of the discharge lamp, thereby supplying the lamp with power for the stable operation,
wherein the controller is further configured to set the first time based on a detection result of the voltage detector and a detection result of the temperature detector.
10. A vehicle, comprising:
a luminaire comprising a discharge lamp electronic ballast, wherein the discharge lamp electronic ballast comprises:
a DC-DC converter circuit configured to convert a voltage of a DC power supply so as to output DC power;
an inverter circuit configured to convert the DC power into AC power to supply the power to a discharge lamp; and
a controller configured to control the DC-DC converter circuit and the inverter circuit,
wherein the controller comprises:
a voltage detector configured to detect a voltage value of the DC power supply or a value corresponding to the voltage value; and
a temperature detector configured to detect a temperature of the ballast or a value corresponding to the temperature of the ballast,
wherein the controller is configured:
during a first time period from a point in time when the discharge lamp is started and a second time period after the first time period, to supply the discharge lamp with power larger than power to be supplied during a stable operation of the discharge lamp;
to supply the discharge lamp with a rated output for a fixed time after the second time period, thereby supplying the discharge lamp with power equal to or larger than a fixed value until a first time elapses from a start of the discharge lamp, the first time including the first time period, the second time period and the fixed time; and
to reduce the power supplied to the discharge lamp when the first time elapses from the start of the discharge lamp, thereby supplying the lamp with power for the stable operation,
wherein the controller is further configured to set the first time based on a detection result of the voltage detector and a detection result of the temperature detector.