Shifting input filter resonances - An intelligent converter behavior for maintaining system stability

Instead of just transforming energy, a modern power converter should incorporate enhanced features to adapt its behavior to its environment. Stability issues in 3-phase power systems with PFC rectifiers incorporating input filters have been a problem for a long time. In this paper a new concept is presented as to how the power converter can shift filter resonances into an unproblematic frequency range by simulating an additional inductivity or capacity. The concept is proved with an extensive stability analysis in the synchronous dq-reference frame. Simulations in the time domain demonstrate the positive impact of the proposed method.