The many different techniques for maximum power point tracking of photovoltaic (PV) arrays are discussed. The techniques are taken from the literature dating back to the earliest methods. It is shown that at least 19 distinct methods have been introduced in the literature, with many variations on implementation. This paper should serve as a convenient reference for future work in PV power generation.

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Comparison of Photovoltaic Array Maximum Power Point Tracking Techniques

Solid-state switch-mode rectification converters have reached a matured level for improving power quality in terms of power-factor correction (PFC), reduced total harmonic distortion at input AC mains and precisely regulated DC output in buck, boost, buck-boost and multilevel modes with unidirectional and bidirectional power flow. This paper deals with a comprehensive review of improved power quality converters (IPQCs) configurations, control approaches, design features, selection of components, other related considerations, and their suitability and selection for specific applications. It is targeted to provide a wide spectrum on the status of IPQC technology to researchers, designers and application engineers working on switched-mode AC-DC converters. A classified list of more than 450 research publications on the state of art of IPQC is also given for a quick reference.

/pdf/a-review-of-single-phase-improved-power-quality-ac-dc-2pm6h4zjxq.pdf

A review of single-phase improved power quality AC-DC converters

Wireless power transfer (WPT) using magnetic resonance is the technology which could set human free from the annoying wires. In fact, the WPT adopts the same basic theory which has already been developed for at least 30 years with the term inductive power transfer. WPT technology is developing rapidly in recent years. At kilowatts power level, the transfer distance increases from several millimeters to several hundred millimeters with a grid to load efficiency above 90%. The advances make the WPT very attractive to the electric vehicle (EV) charging applications in both stationary and dynamic charging scenarios. This paper reviewed the technologies in the WPT area applicable to EV wireless charging. By introducing WPT in EVs, the obstacles of charging time, range, and cost can be easily mitigated. Battery technology is no longer relevant in the mass market penetration of EVs. It is hoped that researchers could be encouraged by the state-of-the-art achievements, and push forward the further development of WPT as well as the expansion of EV.

Wireless Power Transfer for Electric Vehicle Applications

This paper provides a comprehensive review of the maximum power point tracking (MPPT) techniques applied to photovoltaic (PV) power system available until January, 2012. A good number of publications report on different MPPT techniques for a PV system together with implementation. But, confusion lies while selecting a MPPT as every technique has its own merits and demerits. Hence, a proper review of these techniques is essential. Unfortunately, very few attempts have been made in this regard, excepting two latest reviews on MPPT [Salas, 2006], [Esram and Chapman, 2007]. Since, MPPT is an essential part of a PV system, extensive research has been revealed in recent years in this field and many new techniques have been reported to the list since then. In this paper, a detailed description and then classification of the MPPT techniques have made based on features, such as number of control variables involved, types of control strategies employed, types of circuitry used suitably for PV system and practical/commercial applications. This paper is intended to serve as a convenient reference for future MPPT users in PV systems.

A Comparative Study on Maximum Power Point Tracking Techniques for Photovoltaic Power Systems

Acoustic impedance-matched surfaces do not reflect incident waves. Traditional means of acoustic absorption have so far resulted in imperfect impedance matching and bulky structures, or require costly and sophisticated electrical design. Inspired by electromagnetic metamaterials, a subwavelength acoustically reflecting surface with hybrid resonances and impedance-matched to airborne sound at tunable frequencies is now demonstrated.

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Acoustic metasurface with hybrid resonances

This paper presents a high frequency low harmonics content AC source consisted of two phase shifted resonant legs, suitable for driving piezoelectric devices such as those employed in ultrasound radiators. The inverter is characterized by high efficiency, low harmonic distortion, good dynamic response, and simplicity of load power control. Particularly low harmonic content is attained by the proper phase shift between the two inverter legs.

A drive circuit for piezoelectric devices with low harmonics content

A low ripple, compact, high-voltage DC power supply suitable for vacuum system applications is proposed. The design proposed in this paper applies multi-leveling of the Greinacher circuit. By multi-leveling the outputs of several stages the overall ripple and voltage drop are reduced significantly. In addition, the design is simple, does not require additional components and can be implemented without changing the low voltage side of the supply. Both the simulated and measured results show that the proposed power supply topology, when fully loaded, gives a great reduction in voltage drop while maintaining the ripple to less than 1%. As an example the design of a 36kV system, with a 430W load is presented.

Compact multi-level high-voltage power supply for vacuum applications

Operational benefits from smart grid are to some extent the knowledge that's extracted from the big data arriving from smart meters to the meter data management system (MDMS). Smart grid cost is high and the development of ongoing operational benefits is a way to fund part of that cost, as well as to provide new sources of income to utility companies, transferring from a monopoly to liberalized market. From the research point of view, development of operational benefits involves serious scientific creative understanding, and electric algorithms development. Once identifying the potential, there's in addition a development of how to use existing electric knowledge for these applications. In this paper four algorithms are presented: the first are algorithms for remote reverse extraction of grid load structure as a black-box. The second is a non-intrusive load forecasting algorithm sensitive to weather and special days. The third is an algorithm for urban fault location and for low voltage grid real-time fault alert that is both national and urban wide and yet exploits existing infrastructure. The fourth and last is an algorithm for optimal energy management: national, district, and specialized niches such as PV to Grid, EV to Grid. Again identification of novel implementations combined with novel algorithm.

Advanced algorithms for operational benefits in future smart grids

This paper describes the topology and operation of a quasi-resonant driver for LED lighting applications. The proposed driver incorporates a current doubler rectifier and capacitive safety isolation barrier. Variable frequency constant on-time dimming strategy is employed. Capacitive isolation helps eliminating the isolation transformer. The proposed theory is suggested and verified by simulation and experiment.

Quasi resonant LED driver with coupled current doubler rectifier

A novel loss free resistor realization based on a resonant converter is presented. The resonant loss-free resistor is suitable for applications that need a resistive element or high quality rectifier, yet desire a high efficiency and low EMI. Simulations studies were carried out show that the circuit is indeed a loss free resistor and to verify the analysis

Doron Shmilovitz

Papers

A drive circuit for piezoelectric devices with low harmonics content

Compact multi-level high-voltage power supply for vacuum applications

Advanced algorithms for operational benefits in future smart grids

Quasi resonant LED driver with coupled current doubler rectifier

Resonant converter with Loss Free Resistor Characteristic