Date of Award
Spring 1-1-2011
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Electrical, Computer & Energy Engineering
First Advisor
Dragan Maksimovic
Second Advisor
Miguel Rodriguez Gonzalez Date
Third Advisor
Regan Zane
Abstract
Effective power transfer has been one of the main issues in power electronics. In particular, low-harmonic alternating current (AC) shaping is required by various regulations at the interface between AC power grid and direct current (DC) loads or sources,. In order to meet rapidly evolving efficiency standards and environmental concerns, intelligent AC current shaping strategies are required. In the power converter stage, however, inherent uncertainties caused by passive component tolerances and changes in operating conditions may impair the control loop stability, while mis-detection of operating modes over wide load range aggravates the situation further. This thesis introduces an auto-tuning technique in digitally controlled single-phase AC-DC rectifiers and DC-AC inverters. The approach is capable of precise on-line estimation of the power stage passive component values. The control loop compensator parameters are modified adaptively to maintain the nominal stability margins and control loop bandwidth based on the estimated component values. Furthermore, accurate continuous conduction mode (CCM) and discontinuous conduction mode (DCM) boundary detection is achieved as a result of the tuning process, without the need for additional circuitry. Implementation of the tuning approach is relatively simple. The proposed tuning approach is verified on experimental AC-DC and DC-AC prototypes.
Recommended Citation
Moon, Sungwoo, "Auto-tuning of Digitally Controlled Single-Phase Low Harmonic Rectifiers and Inverters" (2011). Electrical, Computer & Energy Engineering Graduate Theses & Dissertations. 23.
https://scholar.colorado.edu/ecen_gradetds/23