A Frequency Response Based Methodology for the Design and Analysis of Active Power Filters Current Control

Active power filters (APFs) are key components to reduce harmonic distortion levels in power systems. However, the design and tuning of APF current control loops is not straightforward due to multiple and sometimes conflicting control objectives, as well as the wide range of available control strategies. Given the large number of possible configurations, relying solely on numerical time-domain simulations for their assessment can become impractical. To overcome this limitation, this paper proposes a methodology based on the use of frequency response functions obtained from analytical models combined with gradient-based optimization. Using the proposed approach, the evaluation of an arbitrarily large number of APF current control designs according to a predefined cost function can be performed with relatively low computation burden. The optimization process is fully automatized. The proposed methodology is validated by means of simulation as well as in an experimental prototype.