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Experimentation is important for learning and research in the field of power electronics and drives. However, a great deal of equipment is required to study the various topologies, controllers, and functionalities. Thus, the cost of establishing good laboratories and research centers is high. To address this problem, the authors have developed a "Power Electronics and Drives Experimental Bench" (PEDEB), whose details are given in this paper. This unique kit includes reconfigurable hardware modules, which can be interconnected to achieve more than 14 different circuit topologies. Moreover, the software (controller) is accessible to users, thereby facilitating quick verification and testing of new ideas. A 2-kVA prototype of the PEDEB was developed and tested for various possible modes of operation. The kit is being used for a first-semester post-graduate laboratory course on "Power Electronics and Drives." This paper includes observations and learning from experiments on dc-dc buck converter, an induction motor drive, and a grid feeding inverter conducted using the PEDEB. (Contains 10 figures and 2 tables.)

To meet the new international efficiency (IE) standards, line-start (LS) synchronous reluctance motors (SyRMs) are now being considered. Conventional star and delta windings are usually employed in LS SyRMs. However, combined star-delta winding has higher winding factor and lower magneto-motive force (mmf) harmonics compared to conventional star and delta windings. Hence, in this paper, LS SyRM and LS ferrite assisted SyRM with star and star-delta winding are analyzed and their performance indices are compared. A winding function analysis is used for the design of star and star-delta windings. Further, the effect of zero sequence current on the performance of the motors under comparison is presented in detail. Star and star-delta winding prototype LS SyRMs with and without ferrite magnets in the rotor are fabricated. Experimental studies are carried-out on these prototypes and the results are presented which are in close agreement with the simulation results. [ABSTRACT FROM AUTHOR]

A high-power low-distortion static var compensator based on a synchronous link converter has been proposed, where the harmonics are eliminated by incorporating a low-power insulated-gate-bipolar-transistor-based controlled current auxiliary converter in conjunction with a high-power gate-turn-off-thyristor-based converter. In this paper, a new load compensator based on this topology is proposed which does not require the information of the voltampere required by the load. As the requirement of the reactive voltampere calculator is eliminated, the scheme becomes insensitive to system frequency variations, temperature, and component aging. The control scheme required for the compensator is developed. The operation of the scheme is validated through extensive simulation studies. Experimental results obtained from a laboratory prototype are provided to demonstrate the viability of the scheme. Index Terms--Harmonic elimination, load compensation, synchronous link converter var compensator, static var compensator, var calculatorless operation.

A high power low distortion static var compensator is proposed in [1]. The harmonics are eliminated by incorporating a low power IGBT based controlled current auxiliary converter in conjunction with a high power GTO based converter. The current reference required by the auxiliary converter is calculated by an involved procedure which makes the overall compensation process complicated. In this paper a simplified control scheme for the var compensator of [1] is proposed. Effectiveness of the proposed scheme is investigated for a case where the var compensator is specifically used for load compensation and also for the case where it is used as a general purpose var generator. Detailed simulation studies of the schemes are presented. Experimental results obtained from a laboratory prototype are provided to demonstrate the viability of the proposed method. Index Terms--SLCVC, SVC, Harmonic elimination, Load Compensator, Var Generator.

AC-to-DC converters based on one-cycle control exhibit instability in current control at light load conditions as well as when they are operating in the inverting mode. In this paper, a modified one-cycle controller for bidirectional ac-to-dc converter is proposed. A fictitious current component in phase with the utility voltage is synthesized. The sum of this current component and the actual load current is compared with the sawtooth waveform to generate the gating pulses for the switches. This modification not only renders stability to the converter at light load conditions and the inverting mode of operations but also enables the converter to seamlessly transfer its operation from the rectifying mode to the inverting mode and vice versa. Detailed simulation studies are carried out to verify the effectiveness of the proposed scheme. To validate the viability of the scheme, detailed experimental studies are carried out on a 2-kW laboratory prototype. [ABSTRACT FROM AUTHOR]

A new three-phase, three-level dc to dc phase shifted pulsewidth modulation (PWM) converter is proposed for high power and high input voltage applications. Output voltage is controlled by incorporating phase shift PWM. Clocked gate signals of each leg are phase shifted by 2π/3 from each other. Major features of the converter include: 1) outer two switches of each leg are turned on and off as zero voltage switching, 2) inner two switches of each leg are turned on and off as zero current switching, and 3) this is achieved without involving any extra passive or active components. The secondary side of the converter is of center tapped full-wave current tripler type. This results in an increase of ripple frequency by a factor of six, leading to a significant reduction in size of the output filter. In order to obtain behavioral and performance characteristics of the proposed converter topology, detailed analytical and simulation studies are carried out. Finally the viability of the scheme is confirmed through detailed experimental studies on a laboratory prototype developed for the purpose. [ABSTRACT FROM AUTHOR]

Presents a study which investigated a quasi-resonant direct current-link inverter. Description of the proposed circuit; Principle in power circuit configuration; Results of simulation experiments.