| 摘要 |
PROBLEM TO BE SOLVED: To simplify the structure of a circuit by forming a DC resonance circuit with the inductance of an exciting coil itself and a resonance capacitor for a high frequency current to excite a discharge bulb. SOLUTION: A switching element 5 connected to a DC power supply 1 at two stages is driven at 2-3MHz with a transformer 8 to perform alternate switching. A high frequency current, when generated, is carried in an exciting coil 2 for a discharge bulb 1 to generate an electromagnetic field for electrodeless discharge lighting. A DC resonance circuit is formed with the inductance of the exciting coil 2 and a resonance capacitor 3 for a desired high frequency current. A high frequency load current carried in the exciting coil 2 is detected by a current detecting winding 14 and fedback to a transformer 8 to continuously self-excite and oscillate the switching element 5. In this way, no other resonance circuits are required for self-exciting and oscillation. |
