Lighting device and illuminating device
AssigneePanasonic Intellectual Property Management Co., Ltd.
InventorKazuya KATO
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Abstract
The lighting device of one aspect according to the present disclosure calculates, based on a voltage value of an AC voltage applied to a discharge lamp and a current value of AC current flowing through the discharge lamp, a first power value defined as a value of power supplied to the discharge lamp in a first half period of the AC voltage and a second power value defined as a value of power supplied to the discharge lamp in a second half period of the AC voltage. The lighting device determines that a ground fault has occurred, when an imbalance state in which a difference between the first power value and the second power value is equal to or greater than a threshold value continues for a predetermined time period.
Claims13
A lighting device, comprising:
- a lighting circuit configured to apply an AC voltage to a discharge lamp;
- a voltage detector configured to measure a voltage value of the AC voltage;
- a current detector configured to measure a current value of AC current flowing through the discharge lamp;
- and
- a controller configured to control the lighting circuit,
- the controller being configured to calculate a first power value defined as a value of power supplied to the discharge lamp in a first half period of the AC voltage and a second power value defined as a value of power supplied to the discharge lamp in a second half period of the AC voltage, based on the voltage value measured by the voltage detector and the current value measured by the current detector, and
- the controller being configured to, when an imbalance state in which a difference between the first power value and the second power value is equal to or greater than a threshold value continues for a predetermined time period, determine that a ground fault has occurred.
Dependencies are inferred from the claim text.