Automatic fluorescent lamp detection for electronic ballasts based on operating frequency and phase shift compensation

Generally, an electronic ballast drives a fluorescent lamp at fixed operating frequency or by regulating the lamp current. Such methods can be used for the designed lamp type and power rating. This paper presents an automatic fluorescent lamp detection for electronic ballasts based on operating frequency and phase shift compensation. The classification of lamp power rating is based on the possibility weight distribution of the lamp operating frequency. Moreover, the phase shift compensation is also included in the detection algorithm in order to address the variations of the resonant circuit parameters. The results from simulation and experiment verify that an electronic ballast with the proposed detection algorithm can automatically detect and drive the fluorescent lamp at the correct lamp power rating.