Nowadays, content-based image retrieval (CBIR) is the mainstay of image retrieval systems. To be more profitable, relevance feedback techniques were incorporated into CBIR such that more precise results can be obtained by taking user’s feedbacks into account. However, existing relevance feedback-based CBIR methods usually request a number of iterative feedbacks to produce refined search results, […]

Environmentally friendly solutions are becoming more prominent than ever as a result of concern regarding the state of our deteriorating planet. This paper presents a new system configuration of the front-end rectifier stage for a hybrid wind/photovoltaic energy system. This configuration allows the two sources to supply the load separately or imultaneously depending on the […]

This paper presents a single-phase multistring five-level photovoltaic (PV) inverter topology for grid-connected PV systems with a novel pulsewidth-modulated (PWM) control scheme. Three PV strings are cascaded together in parallel configuration and connected to a five-level inverter to produce output voltage in five levels: zero, +1/2Vdc, Vdc, −1/2Vdc, and −Vdc. Two reference signals that were […]

A few simple switching structures, formed by either two capacitors and two-three diodes (C-switching), or two inductors and two-three diodes (L-switching) are proposed. These structures can be of two types: “step-down” and “step-up.”These blocks are inserted in classical converters: buck, boost, buck–boost,C´ uk, Zeta, Sepic. The “step-down” C- or L-switching structures can be combined with […]

A novel single-stage high-power-factor (HPF) electronic ballast with boost topology for multiple fluorescent lamps is presented in this paper. HPF at the input terminal is achieved by operating the boost converter in discontinuous conduction mode.With carefully designed circuit parameters, soft switching on the power switches of the resonant inverter can be retained to attain high […]

This paper presents a single-phase five-level photovoltaic (PV) inverter topology for grid-connected PV systems with a novel pulsewidth-modulated (PWM) control scheme. Two reference signals identical to each other with an offset equivalent to the amplitude of the triangular carrier signal were used to generate PWM signals for the switches. A digital proportional–integral current control algorithm […]

In this paper the current harmonic can be compensated by using the Shunt Active Power Filter, Passive Power Filter and the combination of both. The system has the function of voltage stability, and harmonic suppression. The reference current can be calculated by dq transformation. An improved generalized integrator control was proposed to improve the performance […]

Hybrid power systems continuously deliver power to the load from several renewable energy sources. For such systems,the use of a multiple-input converter (MIC) has the advantage of simpler circuit structure and lower cost, compared to the use of several single-input converters. By decomposing converters into basic cells, namely, pulsating source cells and output filters, a […]

This paper introduces a new technique to generate a space vector from a single real-valued signal via complex transfer functions. The single-input space vector concept may be readily integrated within conventional feedback control loops to introduce new controller functionality. In this paper, the single-input space vector is used to regulate a grid-connected ac–dc converter under […]