High‐Order LC‐TT Filter With Dual Anti‐Resonance for Grid‐Connected Inverters

ABSTRACT

Passive power filters are used to mitigate current harmonics in grid‐connected inverters. In conventional filter topologies, inductors with high inductance are required to sufficiently attenuate current harmonics. This paper proposes a novel high‐order filter, referred to as the LC‐TT filter, with two notch characteristics and no resonances between the notches, together with a design procedure that minimizes the total inductance while ensuring system stability under parameter variations. The effectiveness of the LC‐TT filter is demonstrated through comparative analysis with conventional high‐order filters via simulations and experiments. Simulation and experimental results show that the LC‐TT filter reduces the filter size while maintaining sufficient harmonic attenuation.