Electric ballast

[0018] Referring to FIG. 1 , the electronic ballast provided by the present invention includes a filter circuit 1 , a rectifier circuit 2 , an inverter circuit 3 , an output network 4 and a power factor correction circuit 5 . As shown in the figure, when the electronic ballast is in use, alternating current (for example, 50 Hz commercial power) is first input to the filter circuit 1, which is filtered by the filter circuit 1; the filtered alternating current is input to the rectifier circuit 2, which is rectified The circuit 2 converts the alternating current to direct current; the direct current is then input to the power factor correction circuit 5, and the power factor correction circuit 5 obtains lower current harmonic distortion through secondary compensation, so that the power factor of the direct current voltage is increased to 0.999; after that, the inverter circuit 3. Then convert the DC voltage with improved power factor into a high-frequency AC voltage (up to 30 KHz), a