Robust Control of Single Phase PWM Rectifier with Parametric Uncertainties

Application of power-electronic transformers to train traction system is an obvious trend of development. This promote light-weight and small-volume design, and thus enables energy-saving and higher speed of trains. On the other hand, fragile power-electronic components are connected to the grid because traditional transforms are removed. Robustness and fault-tolerant capability of power-electronic transforms become crucial. In this paper H
_∞
controller is proposed for inner-loop control for a single-phase PWM rectifier with parametric uncertainties, frequency perturbation and AC current disturbance. Impact of this control strategy on supply current, output voltage ripple and dq-axis currents is studied. A comparison with linear quadratic regulator (LQR) is presented to prove the robustness of the proposed controller.