Lighting device, lighting apparatus using the same, and lighting system

• US 9,167,665 B2
• Filed: 07/17/2013
• Issued: 10/20/2015
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Takikita, Hisaya, Yamamoto, Masafumi, Hamamoto, Katsunobu
• Primary Examiner(s): Cole, Brandon S
• Application Number:
  US13/944,124
• Publication Number:
  US 20140028196A1
• Time in Patent Office: 825 Days
• Field of Search: 315119-136
• US Class Current: 1/1
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/14 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 47/24 Circuit arrangements for protecting against overvoltage

Abstract

A control unit controls an operation of an electric power conversion unit so that load current that flows through a light source load becomes a constant value, using electric power setting value that is used to determine a size of electric power that is supplied to the light source load and a current detection value that is detected by a current detection resistor (current detection unit), and a load electric power calculation unit obtains load electric power of the light source load using the electric power setting value and a voltage detection value that is detected by a voltage detection unit, and an input electric power estimation unit corrects a circuit loss for the obtained load electric power and estimates input electric power.

Claims

1. A lighting device comprising:

an electric power conversion unit comprising a switching element, configured to adjust load electric power that is supplied to a light source load using DC electric power as an input by ON/OFF of said switching element;

a current detection unit configured to detect load current that flows through said light source load;

a voltage detection unit configured to detect load voltage that is applied to said light source load;

a control unit configured to control an operation of said electric power conversion unit so that said load current that flows through said light source load becomes a constant value, using an electric power setting value that is used to determine a size of electric power that is supplied to said light source load and a current detection value that is detected by said current detection unit;

a load electric power calculation unit configured to obtain load electric power of said light source load using said electric power setting value and a voltage detection value that is detected by said voltage detection unit;

an input electric power estimation unit configured to correct a circuit loss for the obtained load electric power and estimate input electric power; and

a notification unit configured to notify an outside of a calculation result that is obtained in said input electric power estimation unit.

2. The lighting device as set forth in claim 1, wherein

said input electric power estimation unit estimates said input electric power using the corrected circuit loss as a constant value regardless of input voltage and a lighting state of said light source load.

3. The lighting device as set forth in claim 1, wherein

said input electric power estimation unit changes the circuit loss that is corrected using said electric power setting value, based on a lighting state of said light source load and estimates said input electric power.

4. The lighting device as set forth in claim 1, wherein

said notification unit transmits a notification signal that comprises said calculation result of said input electric power estimation unit as a digital signal.

5. The lighting device as set forth in claim 1, wherein

said notification unit transmits a notification signal that comprises said calculation result of said input electric power estimation unit as an analog signal.

6. A lighting apparatus comprising:

the lighting device as set forth in claim 1; and

a fixture body configured to hold the lighting device and said light source load.

7. A lighting system comprising:

a plurality of lighting apparatuses, each of which is said lighting apparatus as set forth in claim 6; and

a reading-out apparatus configured to receive a notification signal that is transmitted from said notification unit of said lighting apparatus and read out said calculation result of said input electric power estimation unit.