| 摘要 |
A transition mode power factor correction converter comprising a boost inductor, a switch, a diode, and output tank capacitor, has circuit means of limitation of the off-time interval of the switch to a fraction of the off-time interval, “complementary” to the on-time interval that is normally controlled for regulating the output voltage, during part of a cycle of a rectified sinusoidal voltage waveform input to the converter, when the current flowing in the inductor reaches a maximum threshold, causing the mode of operation of the device to switch from transition mode to continuous current mode for a middle phase angle region of a rectified sinusoidal input voltage waveform, under high load conditions, defined by said maximum current threshold. Current peaks amplitude and ripple are effectively reduced for same output power. |
| 主权项 |
1. A transition mode power factor correction converter comprising:
a boost inductor; a switch coupled to the boost inductor; a zero current detector configured to sense a zero current condition in the inductor a control circuit configured to:
turn on the switch in response to the zero current condition being detected,turn off the switch after a set on-time interval has elapsed, andlimit an off-time interval of the switch to a fraction of a complementary off-time interval (Toff) of the switch during part of a cycle of a rectified sinusoidal input voltage waveform input to the converter, when current flowing in the inductor reaches a maximum current threshold, causing a mode of operation of the device to switch from discontinuous current mode to continuous current mode for a middle phase angle region of the rectified sinusoidal input voltage waveform under high load conditions, defined by said maximum current threshold. |
