Novel Repetitive Control Technique for Three Phase Four Wire Shunt Active Power Filter

Within the scope of this paper is an illustration of a discrete repeating control mechanism for a three phase, four wire (3P4W) shunt active power filter (SAPF). In power electronics device control designs, it is common practice to make use of two control loops: one with a quick acting inner current control loop and another with a slow acting outside voltage loop. The PI regulator has a hard time keeping track of the reference for the inner current loop since it is periodic. The ability of the repetitive controllers, sometimes known as RC, to follow periodic signals is well known and has earned them widespread recognition. RCs provide great gain at all frequencies. The significant increase in the higher frequency band may contribute to instability. As a direct consequence of this, the sensitivity function of the regular RC will be squared in the research that is being suggested. For the purpose of enhancing the power supply’s overall quality, this project makes use of a fuzzy logic controller. This technique results in a sensitivity function that has a moderate amplitude, and it provides significant notches at frequencies ranging from low to middle, while it creates less notches at higher frequencies. This control approach has been evaluated on the 3P4W SAPF, and it is now being implemented there.