Emerging Converter Topologies and Control for Grid Connected Photovoltaic Systems

Continuous cost reduction of photovoltaic (PV) systems and the rise of power auctions resulted in the establishment of PV power not only as a green energy source but also as a cost-effective solution to the electricity generation market. Various commercial solutions for grid-connected PV systems are available at any power level, ranging from multi-megawatt utility-scale solar farms to sub-kilowatt residential PV installations. Compared to utility-scale systems, the feasibility of small-scale residential PV installations is still limited by existing technologies that have not yet properly address issues like operation in weak grids, opaque and partial shading, etc. New market drivers such as warranty improvement to match the PV module lifespan, operation voltage range extension for application flexibility, and embedded energy storage for load shifting have again put small-scale PV systems in the spotlight. This Special Issue collects the latest developments in the field of power electronic converter topologies, control, design, and optimization for better energy yield, power conversion efficiency, reliability, and longer lifetime of the small-scale PV systems. This Special Issue will serve as a reference and update for academics, researchers, and practicing engineers to inspire new research and developments that pave the way for next-generation PV systems for residential and small commercial applications

Industrial and Technological Applications of Power Electronics Systems

The Special Issue "Industrial and Technological Applications of Power Electronics Systems" focuses on: - new strategies of control for electric machines, including sensorless control and fault diagnosis; - existing and emerging industrial applications of GaN and SiC-based converters; - modern methods for electromagnetic compatibility. The book covers topics such as control systems, fault diagnosis, converters, inverters, and electromagnetic interference in power electronics systems. The Special Issue includes 19 scientific papers by industry experts and worldwide professors in the area of electrical engineering

Measurements, Models, Systems and Design

531 s.

Application of the cascaded multilevel inverter as a shunt active power filter

Abstract unavailable please refer to PD

Voltage sag and momentary interruption ride-through for adjustable speed drives

The awareness of electric power quality has increased over the past decade as electronic equipment has become more susceptible to power disturbances. The most disruptive power disturbances are voltage sags and momentary interruptions and their effect on adjustable speed drives (ASDs) is studied in this thesis. Several solutions have been suggested to provide only voltage sag ride-through to ASDs, but most solutions focus on ASDs with passive rectifiers since they hold the largest share of the market. This thesis focuses on ASDs with active rectifiers, which is an emerging and growing market due to the advantages of four quadrant operation and reduced harmonics offered. A solution is presented which provides an ASD with an active rectifier with the capability to ride through the most common sags in order to reduce the frequency at which the ASD trips and thereby increase its reliability. In order to provide ASDs with the capability to ride through momentary interruptions, it is necessary to interface an energy storage system to the ASD. Flywheels, ultra-capacitors and batteries are evaluated for use in an energy storage system to provide voltage sag and momentary interruption ride-through and a detailed comparison of six systems based on these technologies is presented. The interface circuit between the energy storage system and ASD has a significant influence on the performance of the energy storage system and therefore interface circuits to ASDs with passive and active rectifiers are studied. The addition of an ultra-capacitor energy storage system to an ASD with an active rectifier in order to provide ride-through of deeper sags and momentary interruptions is studied and a fuzzy logic controller is designed to enhance system performance. Initially, no communication between the ASD and the ultra-capacitor system is assumed and the ultra-capacitor system can therefore be added as a retro-fit to an existing ASD. It is, however, foreseen that the market for ASDs with ride-through capability of voltage sags and momentary interruptions will grow and the concepts for an integrated design of an ASD and an energy storage system are presented