Generalized Average-current-mode Control of Single-phase Ac-dc Boost Converters with Power Factor Correction

The dissertation presents a generalized average-current-mode control technique (GACMC), which is an extension of the average-current-mode control (ACMC) for single-phase ac-dc boost converters with power factor correction (PFC). Traditional ACMC is generalized in a sense that it offers improved performance in the form of significant reduction of the current control loop bandwidth requirement for a given line frequency in unidirectional and bidirectional boost PFC converters, and additional functionality in the form of reactive power control capability in bidirectional converters. These features allow using a relatively low switching frequency and slow-switching power devices such as insulated-gate bipolar transistors (IGBTs) in boost PFC converters, including those designed for higher ac line frequencies such as in aircraft power systems (360–800 Hz). In bidirectional boost PFC converters, including multilevel topologies, the GACMC offers a capability to supply a prescribed amount of reactive power (with leading or lagging current) independently of the dc load power, which allows the converter to be used as a static reactive power compensator in the power system. A closed-loop dynamic model for the current control loop of the boost PFC converter with the ACMC has been developed. The model explains the structure of the converter input admittance, the current phase lead phenomenon, and lays the groundwork for development of the GACMC. The leading phase admittance cancellation (LPAC)