Search

A new single-phase power factor corrector (PFC) based on the Sheppard-Taylor topology is studied. Compared with conventional PFCs, this topology facilitates a better input current tracking, lower voltage stresses across the devices and larger output voltage range for the same operating area. The converter is integrated as a PFC at the DC-end of a single-phase diode bridge. Pulse-width-modulated (PWM) multi-loops control schemes are proposed and developed in order to ensure a unity power factor at the AC-source side and a regulated voltage at the DC-load side. The first control method uses the simple and robust hysteretic-based controller; the second employs a conventional PI regulator; and the third is based on the model nonlinearity compensation approach. The design of the last two control methods is based on the knowledge of a mathematical model that would accurately represent the converter. This model is developed in this paper using the state-space averaging technique, and then the small-signal transfer functions of the converter are derived for linear control design purpose. The performance of the different control strategies is evaluated through simulation experiments carried out on a numerical version of the converter. The implemented model of the converter is obtained by using the switching function technique. The control system is tested under both rated and disturbed operating conditions. The system performance is evaluated in terms of source current total harmonic distortion (THD), input power factor, DC voltage stabilization, and regulation following load variations.

In this study, a two-stage DC-DC converter for high current applications is studied. The converter consists of two three-phase full-bridge inverters connected through three AC coupled inductors. A switching-functions-based model of the converter is first established, and then a control scheme is designed for both inverters in order to ensure a high power factor at the AC stage, and a regulated voltage at the DC load. The performance of the proposed control system is verified through numerical simulations. First, an ideal DC source is considered in order to test the performance of the control system, then a proton exchange membrane fuel cell is applied as the DC source in order to highlight the usefulness of this converter in such applications.

Power electronics building blocks (PEBBs)-based design methodology uses off the shelves components and improves scalability and modularity. These PEBB design's approaches need to be unified, approved and standardised. To reach these objectives, most of the research efforts are currently focusing on suggesting a universal control scheme. In fact, the control strategies presented up to date and their methods for generating signals to control power electronic switches are still customised and depend on the control algorithm or on the application. To overcome this issue, a universal strategy is suggested for a universal control protocol for PEBBs. It links the hardware layer to the application layer of the control function and it highly promotes interoperability. Additionally, the suggested interoperable method generates the appropriate control pulses for a wide range of application independently from the control algorithms.