METHOD AND APPARATUS FOR DETECTING AND CORRECTING IMPROPER DIMMER OPERATION

摘要

A system is provided for controlling power delivered to a solid state lighting load. The system being intended to be connected to voltage mains through a dimmer 204 configured to adjustably dim light output of the solid state lighting load. The system comprises a power converter and a phase angle detection circuit. The power converter 220, 620 is configured to drive the solid state light load in response to a rectified input voltage signal originating from the voltage mains. The phase angle detection circuit 210, 610 is configured to detect a phase angle of the dimmer having consecutive half cycles of the input voltage signal, to determine a difference between the consecutive half cycles, and to implement a corrective action when the difference is greater than a difference threshold, indicating asymmetric waveforms of the input voltage signal.