Multiphase machines are nowadays considered for high-power variable-speed drive applications due to numerous advantages that they offer when compared to their three-phase counterparts. Multiphase voltage source inverters are invariably used to provide multiphase variable voltage and variable frequency supply with appropriate pulsewidth modulation (PWM) control. Carrierbased PWM and space vector PWM (SVPWM) are the most common options. This paper is aimed at providing a comprehensive relationship between carrier-based PWM and SVPWM techniques. The relationship is determined in terms of modulation signals and space vectors, modulation signals and space vector sectors, and switching pattern of space vector and type of carrier. Distribution of zero vector is discussed, leading to different types of modulation schemes. The practical implementation issues of carrier-based PWM and SVPWM are discussed. Simulation results and their experimental validation are provided to support the analytical findings.

T his article presents an overview of state-of-art solutions, advances, and design and research trends in medium-voltage (MV) drive technologies-and also discusses the challenges and requirements associated with the use of such drives. The choice and deployment of MV drives in industries are associated with numerous requirements related to the front-end converter (grid side) and inverter (machine side).The focus is on solutions that present high efficiency; low price, size, and weight; minimum harmonic distortion; reduction in dv/dt; mitigation of common-mode (CM) voltage; avoiding torsional vibration; transformerless solutions; fault detection capability; and condition monitoring.The ever-growing demand for electrical energy and the continuous rise in energy prices compel us to conclude that energy must be used more efficiently. Modern power electronics technology with high efficiency and appropriate control approaches is needed in energy-intensive industries to decrease the immense waste of energy and hand and chess pieces image ©istockphoto.com/Vasjakoman circuit image licensed by ingram publishing Challenges and the existing technology 30 IEEE PowEr ElEctronIcs MagazInE z June 2016improve power quality. Since electric motor drive systems are the major consumers of energy, they have the greatest potential for improvement in terms of efficient energy consumption. High-power motors, mostly operating in MV, are of most interest, due to their enormous energy consumption [1].MV drives have found extensive applications in several industries, such as in the oil and gas, petrochemical, mining, water/waste, pulp/paper, cement, chemical, power generation, metal production and processes, traction, and marine drives sectors. To improve power quality and system response and to reduce operation cost and energy loss, the installed MV drives should be adjustable-speed drives (ASDs).

No abstract

No abstract

No abstract