In this chapter, the characteristics of high-voltage SiC IGBT, SiC MOSFET, SiC junction gate field-effect transistor (JFET), and low-voltage SiC MOSFET are discussed.

This chapter introduces the concept and application of power converters using many voltage sources to increase the quality of output voltage and the power rating of those devices. They are called “multilevel converters”(or multilevel inverters) and their mission is to improve efficiency in industrial process and expand applications in new areas such as renewable energy conversion, power transmission and distribution, and transportation. Most of converters used today work with two or three levels of voltage and contribute with important part of total harmonic distortion (THD). The reduction of THD strongly depends on switching frequency of the power semiconductors and are limited to low and medium power conversion. These reasons have generated much interest on the topic of Multilevel Converters [1-5]. Multilevel converters make use of a series connection of switches, which allow the use of switches with reduced voltage ratings. These lower voltage switches have lower conduction losses and can operate at a higher frequency. Higher switching frequencies with many voltage levels result in higher quality voltage waveforms.

This chapter is dedicated to recent advances in multi-input converters. The novel applications for multi-input converters need customized power converter topologies. These topologies need to be synthesized considering the power conditioning requirements of the sources and the loads. The techniques recently proposed for synthesizing multi-input power converter topologies will be introduced in Section 3.2. The trivial multi-input topologies including dc link and ac link configurations will be discussed in Section 3.3. The major applications of the multiinput converters are reviewed in Sections 3.4 and 3.5. Section 3.5 belongs to the renewable energy systems, and Section 3.6 belongs to the vehicular power systems. The specific requirements of the mentioned applications are discussed from a designer point of view in these two sections. Finally, this chapter is summarized in Section 3.7.

In the last two decades, voltage source (VS) topologies based on modular structure have been used in various applications of power electronics, such as power conditioning system (PCS) for renewable energy sources; battery energy storage system (BESS) for power leveling; active power line conditioner (APLC) system for harmonic minimization and reactive power compensation; adjustable speed drive (ASD) system, and high-voltage direct current (HVDC) system. The similarity of modular converters is the unlimited capability of combining identical lowor medium-power subsystems to achieve a system with higher power ratings. Mainly due to the high degree of modularity, modular topologies provide high output energy quality, high reliability, high efficiency, easy maintenance, and cost-weight-volume reduction. All these features are due to the series connection of submodules (SMs), whereas they are identical with the same rated power and can be seen as power cells with similar circuit topology and controlled by the same control and modulation schemes. Thus, for high-power large-scale modular structures, in which the number of power cells per arm (m) are usually more than ten, designing the SMs with standard lowor medium-voltage technology devices has a significant impact on converter efficiency, since it is possible to obtain a high number of voltage levels, allowing an expressive reduction in average switching frequency without compromising the power quality.

Voltage and/or current back-to-back converters are traditionally used to interface an ac source with an ac load. An energy storage element is used to couple the dc-link of the front-end ac-dc rectifier to the back-end dc-ac inverter. A matrix converter (MC), however enables ac-ac conversion without any intermediate energy storage element. Conventional MCs, known as direct matric converters (DMCs), are single-stage converters that connect an m-phase voltage source to an n-phase output load through an m x n array of bidirectional switches. On the other hand, an indirect matrix converter (IMC) requires separate stages for the voltage and current conversion. In this chapter, the most popular MC topologies along with their control and modulation strategies are presented. A brief discussion on the technological and practical issues facing MCs, and a comparative assessment of their performance with the voltage back-to-back converters is given.

Switch-mode power converters are used in a wide variety of applications. In most applications, it is desirable to design high-frequency switching power converters to increase their power density. However, the switching losses are increased by increasing the frequency. Moreover, large dv/dt and di/dt produce electromagnetic interference. To minimize the problems associated with the high-switching frequencies of power converters, several soft-switching techniques have been developed. In this chapter, these techniques will be reviewed.

Impedance-sourced networks provide an efficient means of power conversion between source and load in a wide range of electric power conversion applications (dc-dc, dc-ac, ac-dc, and ac-ac). Various topologies and control methods using different impedance source networks have been presented in the literature, e.g. for adjustable-speed drives, uninterruptible power supply, distributed generation (fuel cell, photovoltaic (PV), wind, etc.), battery or super-capacitor energy storage, electric vehicles, distributed dc power systems, avionics, flywheel energy storage systems, electronic loads, dc circuit breaker, and many more [1-13]. A variety of converter topologies with buck, boost, buck-boost, unidirectional, bidirectional, isolated as well as non-isolated converters are possible by proper implementation of the impedance source network with various switching devices, topologies, and configurations. Figure 7.1 shows the general configuration of an impedance source network for electric power conversion.

Power supplies for modern electronic systems should be small, lightweight, reliable, and efficient. Linear power regulators, whose principle of operation is based on a voltage or current divider, are inefficient. They are limited to output voltages smaller than the input voltage. Also, their power density is low because they require low-frequency (50 or 60 Hz) line transformers and filters. Linear regulators can, however, provide a very high-quality output voltage. Their main area of application is at low power levels as low dropout voltage regulators. Semiconductor components in linear regulators operate in their active (linear) modes. At higher power levels, switching regulators are used. Switching regulators use power electronic semiconductor switches in on and off states. Since there is a small power loss in those states (low voltage across a switch in the on state, zero current through a switch in the off state), switching regulators can achieve high-energy conversion efficiencies. Modern power electronic switches can operate at high frequencies. The higher the operating frequency, the smaller and lighter the transformers, filter inductors, and capacitors. In addition, dynamic characteristics of converters improve with increasing operating frequencies. The bandwidth of a control loop is usually determined by the corner frequency of the output filter. Therefore, high operating frequencies allow for achieving a fast dynamic response to rapid changes in the load current and/or the input voltage.

The advent of power semiconductor technology allowed the integration of semiconductor power devices and their control integrated circuits within the same hybrid device. This chapter has briefly reviewed the advantages of this integration, the technology options, and provided a historical perspective on the topic. Finally, the conventional usage of SPM has been extended with a new class of multi-module power converters based on a network of switches, implemented with multiple SPM and ready to provide even better performance.

The aim of the chapter is to enable the power electronics community to address emerging (but proven) topics in electrical drives, with special emphasis on permanent magnet synchronous motor (PMSM) drives. Among the many alternatives, the collected material was classified according to the type of control, further detailed when necessary for the specific motor topology. The applications (automotive, industry, mechatronics and so forth) are impressively various, and they will be timely cited as soon as they either justify, enrich or aid the comprehension of a particular control technique. Section 10.2 reports the state of the art in sensorless control for PMSM, with the special target of highlighting the delicate connections between any theoretical algorithm and its implementation in the power electronic converter. With the same critical sensibility, Section 10.3 illustrates the direct torque control (DTC) and the model predictive control (MPC), reporting a selected example of application, as bright and promising trend in multi-object, energy-efficient control techniques for PMSM drives.

With more than 85% of electrical motors, induction motors (IMs) dominate the market for electrical motors and consume more than 60% of total industrial electricity across the globe [1]. Their extensive use is a result of their strong low-cost design along with their reliability and cheap maintenance. IMpopularity is not limited to certain applications and IMs are used in a variety of applications with different requirements and constraints. Therefore, control of IMs is regarded as an important field of study ever since introduced. IM drives aim for better efficiency and reliability for IM to achieve more economical operation and to help in energy saving.

Wind turbines (WTs) are of high potential and most promising among renewable energy sources (RESs), largely contributing to world's energy production. Moreover, within renewable energy technologies, wind energy technology is most advanced and the cost of wind power is close to that of fossil fuel power. Recent WT market trends have shown a 12%-13% annual increase in cumulative installed capacity. Such growth rate is anticipated to continue up to 2018, to reaching 596 GW of WT installations. Global leaders in the overall installed capacity of WTs are China, the USA, and Germany; Europe is on the second place behind Asia in the total installed capacity. Most of Europe has good conditions for energy production, hence very fast growing European market holds large producers of WTs, e.g. Enercon, ABB, Siemens, Vestas, Alstom, Gamesa, etc. Further, European wind power industry has formulated generation targets of 180 and 300 GW in 2020 and 2030, respectively

This chapter summarizes the application of power electronics converters and systems in PV energy system. The chapter is organized with introduction given in Section 13.1 to cover the broad view of the PV generation in the context of power system environment. Section 13.2 is dedicated to the power electronic technologies used in PV generation with topics from the state of the art of technologies and the reliability aspects of the PV inverter. In Section 13.3, the system integration is presented to cover integration of the PV inverter with the power system grid and to understand the type of controls and control actions relevant to power system operation, reliability, and stability. In Section 13.4, the standard commonly adopted for PV generation covering different aspects of acceptable grid integration including protection, islanding, power quality, and ancillary services. Finally, in Section 13.5, the field measurement for PV generation is covered.

Owing to recent well-known trends, renewable resources are becoming increasingly prominent in the complex energy market mosaic. As long as their penetration level is low, they can be handled easily by the current infrastructure, but at present incremental rates, this will not be the case in the future. The intermittent nature of solar and wind generation will require a far more flexible compensation mechanism than is currently available. Because of this, large battery banks that act as buffers between the generator and the grid invariably accompany today's renewable energy installations. Wind power, in particular, is not only intermittent but also it has no day-average predictability, as winds can differ hour-to-hour as easily at night as during the day, adding an extra amount of irregularity to an already varying load. This suggests that plug-in electric vehicles (PEVs) will be called on to perform, not only the more manageable regulation tasks, but also aid in providing peak power. As noted earlier, this might not find approval with PEV owners unless the pricing model is modified. Nevertheless, it is reasonable to ask whether a large PEV contracted fleet could perform this task on a national (US) level. Studies have shown that the answer is yes. With an overconfident 50% estimation for the market penetration of wind energy and 70 million PEVs available, peak power could be provided at the expense of approximately 7 kWh of battery energy per day or about 10%-20% of an average PEV reserve.

Electricity has been utilized in some small fashion onboard ships as early as the 1870s, and by the 1930s, it was in widespread use for various auxiliary machinery and even turbo-electric drives. Turbo-electric drives use electric generators to convert mechanical energy of a turbine into electric energy and electric motors to convert it back into mechanical energy to power the drive shafts. It allows for a decoupling of the prime mover from the propellers so that each can operate at optimum speeds without the need for large mechanical reduction gear sets. Although electric drives have long been in use, modern-day shipboard power systems bear little resemblance to their predecessors of even 30 years ago. Present-day shipboard systems employ power electronics for management of energy in propulsion and elsewhere. Fuel costs constitute a large portion of a ship's life-cycle costs and pressures to improve fuel economy in conjunction with environmental regulations in marine engineering have led to the use of power electronic based drives in ship propulsion and auxiliary equipment similarly as in other industrial applications. Many commercial ships are now built with power electronic drives, including passenger ships, tankers, icebreakers, cable laying ships, and floating offshore platforms.

The electrical power system forms the essential backbone of the energy system that enables modern livelihood and supports a comfortable lifestyle for people who have access to it. It is commonly segmented into generation, transmission, distribution, and utilization systems. While electrical power converters have a role to play across all of these segments, their application in generation and utilization systems is rather specific in nature, as has been discussed in various other chapters in this book. The focus of discussion in this chapter is on their application in electrical transmission and distribution system, which are often referred together as the power grid. Since the power grid is largely operated as a three-phase ac system, the discussion in this chapter is mainly focused on three-phase power converters. An outline of different power converters that are used the power grid classified into different categories is presented in Section 16.2. In the discussion, the focus is mainly placed on the circuit configuration of the constituent components, and not on their control, modulation, switching strategy, or design aspects. Such a discussion is beyond the scope of this volume, and may be found in specialized texts, monographs, and references. Various specific applications of these converters in transmission and distribution systems are illustrated in Section 16.3. A brief description of application is restricted to the functional details. Again, detailed discussion of the operation and capabilities of the converters may be found in reference documents. The summary in the concluding section includes a brief discussion of the state of the technology and emerging trends, followed by a list of references.

This chapter presents an overview of DG and microgrids. In Section 17.2, the types of DGs are described with their mathematical models, their technical impacts on the power system and some constraints imposed by standardization. In Section 17.3, microgrids are presented and their features are briefly introduced. Throughout this chapter, a case study is conducted in order to clarify the presented concepts.

Uninterruptible power supply (UPS) systems have been common tools to supply and protect critical loads when the main supply ceases to provide power or the quality of power does not meet load requirements. The need for UPS systems has increased with advancements in information technology, sensitive electronic equipment, and mission critical systems. The UPS concept has moved from rotary to off-line, to on-line, and line-interactive systems, and evolved into multi-layer, multi-bus systems supporting complex infrastructure such as data centers.

WPT can be broadly classified as radiative and non-radiative. Power can be radiated by an antenna and propagates through a medium such as air in the form of a radio frequency (RF) electromagnetic wave. Non-radiative WPT is based on near-field magnetic coupling of magnetic circuits that are generally in the form of conductive loops with a resonant frequency. WPT can be achieved through a range of technologies, ranging from near-field magnetic coupling based technologies operating at a relatively low frequency (such as 10 kHz-15.65 MHz) to microwave technologies operating at relatively high frequency (up to a few giga-hertz). This chapter focuses primarily on the former type of research and applications based on near-field magnetic coupling. It covers WPT research and applications from low-power applications.

Power electronic systems (PESs) are nonlinear hybrid dynamical systems [1]. The instability in such switching systems, owing to their discontinuity, can evolve on slow and on fast scales [2]. Conventional analyses of PESs and their subsystems are based on averaged models, which ignore the fast-scale instability and analyze the stability on a reduced-order manifold [1-3]. As such, validity of the averaged models varies with the switching frequency even for the same topological structure. The prevalent procedure for analyzing the stability of standalone and networked PESs is based on linearized averaged (small-signal) models that require a smooth averaged model. Yet there are systems (in active use) that yield a non-smooth averaged model. Even for systems for which smooth averaged model is realizable, small-signal analyses of the nominal solution/orbit do not provide anything about three important characteristics: region of attraction of the nominal solution, dependence of the converter dynamics on the initial conditions of the states, and the post-instability dynamics. As such, conventional linear controllers for PESs, designed based on small-signal analyses, may be conservative and may not be robust and optimal.