Non iterative design procedure of LCC-based electronic ballasts for fluorescent lamps including dimming operation

The design process of LCC-based electronic ballasts for fluorescent lamps is reviewed with the aim of defining a non iterative procedure that allows to satisfy all the constraints, while minimizing the RMS current in the circuit. An original approach, based on the comparison of different quality factors, is derived that easily yields the ratio between the operating and resonance frequencies. This is the base on which all the design procedure is built. Moreover, the proposed approach allows to find the operating frequency variation as well as to analyze the lamp filament power during dimming operation. Different designs have been carried out to demonstrate the potentiality of the proposed design approach. The theoretical expectations have been validated through experimental results.