RESONANCE INVERTER DRIVING METHOD USING ZERO-CURRENT SWITCHING AND PULSE WIDTH MODULATION OF ARBITRARY FREQUENCY

摘要

PROBLEM TO BE SOLVED: To reliably carry out zero-voltage switching of an inverter transistor in frequency modulation control of a resonance inverter used in an electronic stabilizer that supplies power to a gas discharge lamp.;SOLUTION: An inverter circuit 10 includes a half bridge inverter 14 connected to a DC power source 16 and a serial resonance circuit 22. The half bridge inverter 14 has a top inverter switch 28 and a bottom inverter switch 30, and switchover between the top inverter switch 28 and the bottom inverter switch 30 is carried out by an inverter drive circuit. The inverter drive circuit detects a current IL flowing through a resonance inductor 24. A zero-cross detecting circuit 32 carries out switchover between the top inverter switch 28 and the bottom inverter switch 30 (a) at a frequency close to the resonance frequency of the resonance circuit 22 (b) in synchronization with a specific rate of change of the current IL flowing through the resonance inductor 24.;COPYRIGHT: (C)2011,JPO&INPIT