Self running converter utilizing partial resonance

Novel zero-voltage-switched (ZVS) quasiresonant converters (QRCs) utilizing partial resonance are presented. The partial-resonance technique overcomes high-voltage stress in the ZVS resonant converter by adding a clamp mode between resonant modes while the power transistor is off. A novel self-running converter whose frequency is determined by the saturable inductor is proposed. The self-running converter uses partial resonance that has interesting characteristics and is able to control output voltage easily. Experimental results show that zero cross switching and low EMI (electromagnetic interference) are achieved using this approach