A new flicker mitigation technique for zero-crossing AC power control

The zero-crossing AC power control usually does not generate harmonics and Electromagnetic Interference (EMI) since it does not chop the voltage signal. In contrast, it is almost inevitable the emergence of flicker on the electric grid, mainly due to the large electrical power consumed by heating equipment, comprised by long ON and OFF state intervals, characteristic of the technique. Regarding this matter, this paper presents an algorithm that improves this technique concerning the generation of flicker. Besides reducing the problem of flicker in the power grid, this proposal also allows the use of multiple power levels using a single heating element. Theoretical and experimental comparisons that demonstrate the feasibility and the gains achieved by the proposed algorithm are presented. By means of the technique proposed in this paper is possible to obtain a reduction on flicker up to 350% compared to the traditional technique.