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Switched reluctance machine (SRM) has progressed as a suitable contender in the family of electrical machines for its high starting torque and better performance in different operating conditions. The need for accurate modeling of this machine is, therefore, dependent on the accurate determination of losses of which iron loss is exigent. This article aims to determine iron loss from the equivalent circuit parameters of the machine based on the input data tables that are directly obtained from the experiments carried out on an existing four-phase, bifilar wound SRM. The procedure and necessary steps for the loss separation method are well defined and supported by the theoretical and practical results. The experimental determination of the iron losses has been compared with the predicted results under the same operating conditions. [ABSTRACT FROM AUTHOR]

In this article, a new low-cost small-scale three-phase brushless motor topology is proposed. This is a new topology for self-excitation of brushless wound rotor synchronous motor investigated initially for rated speed. For brushless excitation, the stator is designed to contain two windings, namely, three-phase armature winding and exciter winding. The rotor consists of two windings, that is, harmonic winding and field winding, and a diode rectifier. An inverter feeds the three-phase armature winding which is connected in series through an uncontrolled three-phase rectifier to a single exciter winding. When the current is supplied from the inverter, both the armature and exciter windings are energized eventually producing a flux in the air gap. Since the flux produced by the exciter winding is not synchronized with the field winding, it produces a harmonic to be intercepted by the harmonic winding on the rotor. Eventually, the voltage produced in the harmonic winding is used to feed dc current to the field winding for brushless operation. The results obtained by 2-D finite-element analysis (FEA) validate the brushless operation of the motor. The proposed motor is analyzed basically for topology verification with the FEA results. Since the topology can be verified, further effort can be put to investigate such low-cost topologies for brushless wound rotor synchronous motor. It can be an alternative to a costly permanent magnet synchronous motor for specific applications. [ABSTRACT FROM AUTHOR]

Numerous industrial facilities involve the installation of load transformers with their respective loads. As these loads are engaged and disengaged, their transformers are also energized and de-energized, respectively. An inrush current, which typically occurs when a transformer is energized, can easily be observed for an online uninterruptible power supply (UPS) system feeding such loads. This paper proposes an online UPS system that eliminates the inrush current phenomenon caused by the switching-in of the load transformers. The UPS inverter specifically utilizes a fast acting current control scheme which enables it to regulate the load current during all energizing conditions of the load transformer connected to the UPS system. Experimental results are provided to validate the effectiveness of the proposed UPS system. [ABSTRACT FROM PUBLISHER]

Presents corrections to author names and affiliations in the paper, ?An online UPS system that eliminates the in rush current phenomenon while feeding multiple load transformer,? (Bukhari, S.S.H.),IEEE Trans. Ind. Appl., vol. 53, no. 2, pp. 1149?1156, Mar./Apr. 2017. [ABSTRACT FROM PUBLISHER]