Navid Golbon

A Low-Power AC–DC Single-Stage Converter With Reduced DC Bus Voltage Variation

A new low-power single-stage ac-dc converter is proposed in the paper. The outstanding feature of the converter is that it can operate with a sinusoidal input current and a low primary-side dc bus voltage that is much less variable than that found in other single-stage converters. The operation of the converter is discussed in the paper and its various modes of operation are explained in detail. An analysis of the converters steady-state characteristics is performed and the results are used in the design of the converter. Experimental results obtained from a prototype converter are also presented.

A new control scheme for an AC-DC single-stage buck-boost PFC converter with improved output ripple reduction and transient response

The main objective of this paper is to minimize the 120 Hz output ripple component and improve the dynamic response of an AC-DC single-stage power factor correction (PFC) buck-boost converter by using a new control scheme. In the paper, the operation of the single-stage converter is briefly reviewed and the proposed control method is introduced and explained in detail. Key design considerations for the design of the converter controller are discussed and the converters ability to operate with fixed DC bus voltage, low output ripple and fast dynamic response is confirmed with experimental results obtained from a prototype converter.

A novel ac-dc single-stage converter for low power applications

A new single-stage ac-dc converter that can operate with a low primary-side dc bus voltage that is much less variable than that found in other single-stage converters is proposed in the paper. The operation of the converter is discussed in the paper and its various modes of operation are explained. Several key relations are derived and used in the design of the converter. Experimental results obtained from a prototype converter are also presented.

A control strategy for a solar grid-connected inverter

In this paper, the control of a grid-connected inverter is investigated. There are two key control issues that need to be examined. The first is the control of the AC side of the converter to ensure that sinusoidal output waveforms are produced and that the DC bus capacitor voltage that the six-switch bridge see is fixed. It will be assumed in this paper that the output of the inverter is being fed to the grid. The second key issue that needs to be examined is the current that is fed from the PV panels to the inverter. The ripple on this current must be minimized as much as possible so that the inverter can be implemented with maximum power point tracking techniques (MPPT) that will enable it to extract the maximum power that is available from the PV panels at any given time.

Analysis and design of a higher current ZVS-PWM converter for telecom applications

A new auxiliary circuit that can be implemented in dc-dc and ac-dc ZVS-PWM converters is proposed in the paper. The circuit is for ZVS-PWM converters used in applications where high-frequency operation is needed and the load current is higher than that of typical ZVS-PWM converters. In the paper, the operation of a new ZVS-PWM converter is described, its steady-state operation is analyzed, and a procedure for its design is derived and then demonstrated. The feasibility of the new converter is confirmed by experimental results obtained from a prototype.

A Comparative Study of Buck-Boost and Boost AC-DC Single-Stage Flyback Converters

Two low power single-stage flyback converters are compared in this paper. The only difference in topology of the two converters is the power factor correction (PFC) section. One has been designed based on buck-boost and the other one was implemented by boost converter. Features, specifications and performance of the two converters are compared in detail in this paper.

A DC-DC converter with stacked flyback converters

This paper proposes a new two-switch flyback converter that allows its switches to operate with less peak voltage stress than other flyback converters and with double their power transfer frequency. Moreover, the converter can operate with zero-voltage switching (ZVS) using just one auxiliary switch. In the paper, the operation of the proposed converter is explained. The converters modes of operation are discussed in detail and analyzed so that the converters steady-state characteristics can be determined. Based on these characteristics, a procedure for the design of the converter is established and the procedure is demonstrated with a detailed design example. Experimental results obtained from a prototype converter that confirm the feasibility of the converter are presented.

Analysis and design of an AC-DC single-stage buck-boost full-bridge converter

A new AC-DC single-stage, buck-boost, full-bridge converter is proposed in the paper. The outstanding features of the converter are that it can operate with an excellent input power factor with and a dc bus voltage that is less than 450 V. In the paper, the operation of the converter is discussed in detail, its steady-state characteristics are examined, and a design procedure is developed. The feasibility of the converter is confirmed with experimental results obtained from a prototype converter.

An AC-DC single-stage full-bridge converter with buck-boost input section

A new AC-DC single-stage PWM full-bridge converter is proposed in the paper. The outstanding features of the converter are that it can operate with an excellent input power factor, and a DC bus voltage that is always less than 450 V and that has much less variation with line and load change than boost-type single-stage converters. In the paper, the operation of the converter is explained, its design is discussed, and experimental results that confirmed its feasibility are presented.

A ZVS technique for single-switch PWM converters implemented with paralleled MOSFETS

It is common practice to implement the main power switch in single-switch, pulsewidth modulated (PWM) converters as a combination of parallel MOSFETs to reduce conduction losses. This is done in higher power applications where high switching frequency operation is required and a significant amount of current flows in the converter. An auxiliary circuit is typically used to help the main power switches turn on with zero-voltage switching (ZVS), but previously proposed auxiliary circuits are limited in power and are not suited to higher power applications. In the paper, a new auxiliary circuit that can be used in applications where paralleled MOSFETs are used is proposed. The operation of a boost converter operating with the new auxiliary circuit is described, and general guidelines for the design and implementation of the converter are given. The feasibility of the auxiliary circuit is confirmed by experimental results obtained from a boost converter prototype.