Robust PID Controller for DC-DC Boost Converter Feeding CPL

Power electronics converters with constant power loads (CPL) exhibit negative incremental impedance characteristics, which can affect the converter regulation performance and may cause instability. A robust QFT approach is proposed in this paper to improve the regulation performance and maintain the robust stability of the boost converter system with CPL. Loop shaping technique is employed to design a robust PID controller with disturbance dynamics in the QFT approach. The advantage of the proposed QFT based design is demonstrated by the means of simulations of a boost converter supplying a CPL