Detecting output diode conduction time for cable drop compensation of a power converter

摘要

An example controller for a power converter to provide power to a load through a distribution network includes a control circuit and a cable drop compensator. The control circuit outputs a drive signal to control switching of a switch to regulate an output of the power converter in response to a feedback signal. The cable drop compensator is coupled to adjust the feedback signal in response to a conduction time of an output diode of the power converter to compensate for a distribution voltage dropped across the distribution network.

主权项

1. A controller for a power converter to provide power to a load through a distribution network, the controller comprising:
a control circuit that outputs a drive signal to control switching of a switch to regulate an output of the power converter in response to a feedback signal; and a cable drop compensator configured to sink current from a feedback terminal of the controller to adjust the feedback signal in response to a conduction time of an output diode of the power converter to compensate for a distribution voltage dropped across the distribution network, wherein the cable drop compensator comprises:
a comparator coupled to compare the feedback signal with a threshold value and to output a first signal indicating whether the output diode is conducting;a feedback adjuster coupled to adjust the feedback signal in response to the first signal indicating that the output diode is conducting; andan averaging circuit that outputs a second signal in response to the first signal, wherein the second signal indicates an average conduction time of the output diode, and wherein the feedback adjuster is coupled to receive the second signal and to adjust the feedback signal in response thereto.