This paper describes the modeling and control of a three-phase grid-connected converter fed by a photovoltaic array. The converter is composed of an isolated DC-DC converter and a three-phase DC-AC voltage source inverter The converters are modeled in order to obtain small-signal transfer functions that are used in the design of three closed-loop controllers: for the output voltage of the PV ar...

A simple step and search control strategy for extracting maximum output power from grid connected Variable Speed Wind Energy Conversion System (VSWECS) is implemented in this work. This system consists of a variable speed wind turbine coupled to a Permanent Magnet Synchronous Generator (PMSG) through a gear box, a DC-DC boost converter and a hysteresis current controlled Voltage Source Converte...

This review paper discusses power quality considerations for direct current (DC) electric power distribution systems, particularly DC microgrids. First, four selected sample DC architectures are discussed to provide motivation for the consideration of power quality in DC systems. Second, a brief overview of power quality challenges in conventional alternating current (AC) distribution systems i...

A novel current controlled CMOS ring oscillator is presented in this paper. Specially circuit structure and transistor parameters design is used to obtain good temperature coefficient. The designed ring oscillator circuit has been used in a CMOS step-up switching regulator controller which has been implemented using a 0.5μm double poly double metal CMOS technology. The test result shows that th...

This paper describes the analysis and design of a low cost three phase inverter brushless dc motor (BLDC) drive.For effective utilization of the developed system, a novel direct current controlled pwm scheme (DPC)is designed and implemented.. The operational principle of the four-switch BLDC motor drive and the developed control scheme are theoretically analyzed and the performance is demonstra...

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 ...

In this paper, the dynamics of a DC-DC boost power converter under variable structure control is studied applying bifurcation analysis techniques. The switching hyperplane coefficients are considered as bifurcation parameters. The dynamic phenomena detected in this work suggest new types of sliding bifurcations. This analysis is relevant in the context of sliding mode control with auxiliary ada...

Illumination non-homogeneity is the main problem which affects dense-array CPV systems. In a previous work we theoretically showed that connecting each cell in the array to a DC–DC converter module, leads to an increase of the power transfer efficiency with respect to classical series connection. This finding is here confirmed by two experiments making use of a cells’ array, one for a certain c...

This paper proposes a novel auto-reset forward DC-DC converter with inductor-switching technique to obtain the high performance by means of zero voltage switching and the fast transient response at steep load variations. The performance of the forward converter is strongly depending on the transformer reset-method. The Auto-reset method is used to recover the energy stored in leakage inductance...