Power conversion with controlled capacitance charging including attach state control

摘要

An electronic system includes a controller that actively controls a rate of charging and discharging of an energy storage capacitor to maintain compatibility with a dimmer. The controller actively controls charging of a capacitor circuit in a switching power converter to a first voltage level across the capacitor circuit. The controller further allows the capacitor to discharge to obtain a second voltage level across the capacitor circuit. The second voltage level is sufficient to draw a current through a phase-cut dimmer to prevent the dimmer from prematurely resetting. The first voltage is sufficient to allow the capacitor to discharge to the second voltage level during each cycle of the line voltage.

主权项

1. A method comprising:
actively controlling a rate of charging of a capacitor circuit in a switching power converter to a first voltage level across the capacitor circuit, wherein actively controlling the rate of charging of the capacitor circuit comprises actively controlling conductivity of a switch coupled to the capacitor circuit, and the conductivity of the switch controls current flow in a sole current path for current charging the capacitor circuit; and allowing the capacitor to discharge to obtain a second voltage level across the capacitor circuit, wherein the second voltage level is sufficient to draw a current through a phase-cut dimmer to prevent the dimmer from prematurely resetting, and the first voltage is sufficient to allow the capacitor to discharge to the second voltage level during each cycle of the line voltage.