Robustness analysis of a rectifier in half bridge configuration with unity power factor

This paper presents a practical application of a modern methodology for analyzing the effects of structured uncertainty in the internal stability of the current control loop of a rectifier with unitary power factor in half bridge configuration. The proposed approach is based on the complementary combination of two main mathematical concepts: the Linear Fractional Transformation (LFT) and the Structured Singular Value Function (SSV or μ). The LFT is used as a matrix function that allows a unified representation of different types of model uncertainty and SSV provides a necessary and sufficient condition for the robustness test with a moderate amount of computation complexity. The methodology is applied to a Rectifier that was designed and implemented by the Research group in control systems and power electronics (CEPIT) of the Pontificia Universidad Javeriana under the project “Voltage Rectifier Controlled by a DSP with power factor correction and low harmonics content”, financed by the internal call for supporting the research activity in the Pontificia Universidad Javeriana.