Grid connected static power converters inject parasitic DC currents due to the offset in current sensing, control imperfections, asymmetries in power switches and other secondary effects. Ever growing number of grid connected converters contributes to an increase of DC bias in AC grids, and this brings the cores of distribution transformers closer to saturation and increases their power losses....

This paper presents a new nonlinear backstepping controller for a direct-driven permanent magnet synchronous generator-based wind turbine, which is connected to the power system via back-to-back converters. The proposed controller deals with maximum power point tracking (MPPT) in normal condition and enhances the low-voltage ride-through (LVRT) capability in fault conditions. In this method, to...

– In recent years it has been observed that some power converters can exhibit deterministic chaos. Since converters have wide industrial applications, it is useful to study their bifurcation phenomena in order to understand the change of behaviors as circuit parameters are varied. Therefore this paper aims to investigate some complex dynamic phenomena that can occur in currentprogrammed DC-DC b...

As the deployment of distributed generation continues, an increasing number of DC/AC power inverters will be interfaced into the electric grid. Groupings of these power inverters, along with distributed storage and load, are referred to as microgrids. Microgrids offer the potential for unprecedented reliability and flexibility, but also pose new control challenges. Inverters in microgrids must ...

Conventional dc-dc boost converters are unable to provide high step-up voltage gains due to the effect of power switches, rectifier diodes, and the equivalent series resistance of inductors and capacitors. In this paper a Linear Peak Current Mode Controller (LPCM) for a transformerless dc-dc converters is proposed to achieve high step-up voltage gain without an extremely high duty ratio. In the...

Half-bridge inverter is very suitable for singlephase on-line UPS applications because it offers very desirable features. These include fewer active switches, a common neutral connection – not requiring an isolation transformer, and sinusoidal input currents if a power factor correction (PFC) converter is used at the front end. This paper presents a comparative study of PFC converters for singl...

---------------------------------------------------------------------***--------------------------------------------------------------------Abstract Micro-grid is a novel conceptual power system for smooth installation of many Distributed Generators which is used for distributing the power in order to provide high quality. The most of micro-grids adopt ac distribution as well as conventional po...

This paper presents an approach for teaching and learning dc-dc converter design using MathCAD. MathCAD provides advantages that greatly improve teaching and learning process especially when long and complicated design equations are involved such as those found in dc-dc converters. A design example using Excel is presented and then compared with the same example using MathCAD. Experience learne...

This paper investigates the effect of several frequency modulation profiles on conducted-noise reduction in dc-dc converters with programmed switching controller. The converter is operated in variable frequency modulation regime. Twelve switching frequency modulation profiles have been studied. Some of the modulation data are prepared using MATLAB software, and others are generated online. More...

the aim of this paper is to design a fractional order sliding mode controllers (fosmc)for a class of dc-dc converters such as boost and buck converters. firstly, the control lawis designed with respect to the properties of fractional calculus, the design yields an equiv-alent control term with an addition of discontinuous (attractive) control law. secondly, themathematical proof of the stabilit...