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Introduces the definition of electric power quality, its causes and classification: transients, short-duration voltage variations, interruptions, sags, swells, long-duration voltage variations, sustained interruption, under- and over-voltage, voltage imbalance, waveform distortion, DC offset, harmonics, inter-harmonics, non-integer harmonics, triplen harmonics, sub-harmonics, time and space harmonics, characteristic and uncharacteristic harmonics, positive-negative- and zero-sequence harmonics, notching, electric noise, voltage fluctuation and flicker, and power-frequency variations. The formulations and measures used for power quality; impacts of poor power quality on power system and end-use devices; most important IEEE and IEC guidelines/recommendations/standards referring to power quality; modelling, mitigation and elimination techniques for power quality phenomena are presented. 9 application examples with solutions and 15 application-oriented problems are listed.

Investigates the optimal placement and sizing of shunt capacitor banks in the presence of harmonics. It includes the concept of reactive power compensation based on capacitors, and common types of shunt capacitor banks used in power systems. A survey of various optimization algorithms for the placement and sizing of shunt capacitor banks under sinusoidal operating conditions is listed, such as analytical methods, numerical programming methods, heuristic methods, artificial intelligence-based methods, genetic algorithms, expert systems, simulated annealing, artificial neural networks, fuzzy set theory, graph search algorithm, particle swarm algorithm, tabu search algorithm, and sequential quadratic programming. The analysis and comparison of various solution approaches for the optimal placement and sizing of fixed capacitor banks in the presence of voltage and current harmonics are outlined. This chapter includes 8 application examples with solutions.

Addresses the impact of poor power quality on reliability, relaying, and security as well as impacts of harmonics and inter-harmonics affecting the operation of overcurrent and under-frequency relays, which has not been published in any textbook. It discusses reliability indices, degradation of reliability and security, electromagnetic field (EMF), corona of transmission lines, load sharing, droop characteristics, cogeneration, and frequency/voltage control which are very important and complicated if renewables operate within a distribution system. Maximum error and uncertainty analyses are applied to the direct-loss measurement of three-phase transformers under non-sinusoidal operating conditions. CBEMA and ITIC tolerance curves, load shedding, energy-storage methods, and matching intermittently operating renewable power plants conclude this chapter. 14 application examples with solutions and 17 application- oriented problems are included.

Investigates aging and lifetime reduction of transformers and induction machines due to elevated temperatures caused by harmonics. The additional temperature rise caused by harmonics is defined by a weighted-harmonic factor function which has not yet been published in a textbook. The Arrhenius reaction rate equation is relied on to estimate the reduction in lifetime of motors and transformers due to harmonic voltage magnitudes. Harmonic limits within single- and three-phase power systems are proposed and rigid harmonic spectra are not recommended. The probabilistic and time-varying nature of harmonics and their incurred cost are reviewed. Various operating regimes of electric machines are investigated from a lifetime reduction point of view. Heat flow relations due to radiation and convection are given with their associated thermal equivalent circuits. 11 application examples with solutions and 11 application-oriented problems are included.

Investigates the performance of induction machines as a function of the power system’s fundamental and harmonic voltages/currents. It includes sinusoidal model of induction machine, time and space harmonics, forward- and backward-rotating harmonic magnetic fields, and magnetic field- and torque calculations based on the finite-difference method. The steady-state stability of rotating machines is reviewed, and the extension of the variable-speed range is obtained through compensation of flux weakening. Fundamental, integer, inter-, fractional and sub-harmonic torque characteristics of three-phase induction machines are analysed. The interaction of space and time harmonics, voltage-stress winding failures, classification and available harmonic models of induction machines as well as discussions of rotor eccentricity are provided. 14 application examples with solutions and 14 application-oriented problems are listed.

Investigates interaction of harmonics with capacitors. First the main applications of capacitors in power systems are outlined: power factor correction, definitions of displacement power factor and total power factor which includes harmonics. Thereafter, the power quality issues associated with capacitors are discussed, including series and parallel harmonic resonances, and transients due to capacitor switching. Frequency and capacitance scanning techniques including harmonic voltage, current and reactive-power constraints for capacitors are addressed next. Feasible exemplary operating regions for safe operation of capacitors in the presence of voltage, current and reactive-power harmonic components are investigated. Equivalent circuits of capacitors in terms of inductance, resistance, and capacitance are reviewed. 9 application examples with solutions and 10 application-oriented problems are listed.

Chapter 4 reviews non-sinusoidal operation and harmonic models of synchronous machines: electrical and mechanical equations and their model in dq0-coordinates suitable for sinusoidal operation, phasor diagrams and magnetic-field solutions to determine model inductances with or without saliencies. Behaviour of synchronous machines under various commonly occurring faults, e.g., balanced and unbalanced short-circuits, out-of-phase synchronization, and reclosing is analysed. Neodymium-iron-boron permanent-magnet machines are studied. Guidelines for flux- and current-density values are given. Switched-reluctance machine fields and the calculation of forces based on the Maxwell/Stratton/Reichert stress conclude this part, where the winding forces of a synchronous generator during short-circuit are presented. The influence of harmonics and various harmonic models of synchronous machines are explained. 16 application examples with solutions and 17 application-oriented problems are listed.

Purpose of the study: The need for knowledge, skills, expanding the established functionality of a professional is increasing more and more. That is why young professionals-trans-professionals, who are able to realize themselves not only in one sphere but who are ready to delve into problems of other, absolutely "foreign" for the scientific and technical fields and cooperate effectively with specialists of these areas in one team, will be responsible for creation of new technologies determining the wellness of our country. The article is aimed at the analysis and generalization of foundations of the convergence and identifying its sense-creating content in the development of trans-professionalism as an integral characteristic of the activity subject in a rapidly changing social-professional environment. Methodology: The leading methods in the study of this problem are the theoretical and methodological analysis of the subject and the problem of the research based on the study and logical generalization of scientific literature. Description of the phenomenon of convergence and trans-professionalism was carried out based on multidimensional, transdisciplinary, project and process approaches. Results: The results of the study are content components of trans-professionalism of the activity subject, justification of the convergence theory as a fundamental basis of integration of educational content and new technologies as well as technology foresight of the formation of trans-professionalism of subjects on the basis of convergence. Applications of this study: Materials of the article may be interesting for methodologists, Methodists, and teachers of the continuous professional education system. Novelty/Originality of this study: The components that allow combining the different parameters of the activity subject, showing its qualitative change in the problem field of trans-professionalism, are stated to be the content components of trans-professionalism for activity subjects. The methodology of convergence provides a synergistic effect of the interaction of social-humanitarian and natural sciences. Improving the process of development of trans-professional competencies of activity subjects is associated with the development of new technologies-tools and methods. © Zeer et al. The article is published with the financial support of the grant of the RFBR 18-013-01147 "Social and humanitarian paradigm of the formation of trans-professionalism of the subjects of socionomic professions".

The science guiding the EUREC⁴A campaign and its measurements is presented. EUREC⁴A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. Through its ability to characterize processes operating across a wide range of scales, EUREC⁴A marked a turning point in our ability to observationally study factors influencing clouds in the trades, how they will respond to warming, and their link to other components of the earth system, such as upper-ocean processes or the life cycle of particulate matter. This characterization was made possible by thousands (2500) of sondes distributed to measure circulations on meso- (200 km) and larger (500 km) scales, roughly 400 h of flight time by four heavily instrumented research aircraft; four global-class research vessels; an advanced ground-based cloud observatory; scores of autonomous observing platforms operating in the upper ocean (nearly 10 000 profiles), lower atmosphere (continuous profiling), and along the air–sea interface; a network of water stable isotopologue measurements; targeted tasking of satellite remote sensing; and modeling with a new generation of weather and climate models. In addition to providing an outline of the novel measurements and their composition into a unified and coordinated campaign, the six distinct scientific facets that EUREC⁴A explored – from North Brazil Current rings to turbulence-induced clustering of cloud droplets and its influence on warm-rain formation – are presented along with an overview of EUREC⁴A's outreach activities, environmental impact, and guidelines for scientific practice. Track data for all platforms are standardized and accessible at https://doi.org/10.25326/165 (Stevens, 2021), and a film documenting the campaign is provided as a video supplement.