Patent ID: 8912768

Claim:
A voltage clamp step-up boost converter comprising: a leakage inductor having a first end connected to a first end of a power supply unit; a tapped inductor having a first end connected to a second end of the leakage inductor; a magnetizing inductor having a first end connected to the second end of the leakage inductor and a second end connected to a second end of the tapped inductor; a switch having a first end connected to the second end of the tapped inductor and a second end connected to a second end of the power supply unit; a first diode having a first end connected to the second end of the tapped inductor; a second diode having a first end connected to a second end of the first diode and a second end connected to a third end of the tapped inductor; a resonant clamp capacitor having a second end connected between the second end of the first diode and the first end of the second diode and a first end connected between the first end of the power supply unit and the first end of the leakage inductor, the resonant clamp capacitor being configured to perform the clamping of the voltage across the switch and zero-voltage switching thereof when the switch is turned-off; an output capacitor having a first end connected to the second end of the second diode and a second end connected to the second end of the switch; an output load resistor having a first end connected to the first end of the output capacitor and a second end connected to the second end of the output capacitor; and a blocking capacitor having a first end connected to the third end of the tapped inductor and a second end connected to the second end of the second diode, wherein when the switch is turned-on, the voltage clamp step-up boost converter is configured to form a first conductive path through the power supply unit, the resonant clamp capacitor, the blocking capacitor, the tapped inductor, and the switch and cause resonance through the resonant clamp capacitor and the leakage inductor to decrease a voltage applied to the resonant clamp capacitor to a negative (−) voltage, thereby making the switch to be zero-current turned-on; and wherein when the switch is turned-off, the voltage clamp step-up boost converter is configured to form a second conductive path through the leakage inductor, the tapped inductor, the first diode, and the resonant clamp capacitor to increase the voltage applied to the resonant clamp capacitor to a positive (+) voltage, thereby making the switch to be zero-voltage turned-off.