Electronic communication technologies continue to change the landscape of reference services. For many users, virtual communication is the preferred means of conversing. Synchronous virtual reference, similar to other synchronous means of communication, is an important method for reaching students and for providing teaching and learning opportunities. Grounded Theory (GT) research provides a me...

We construct a set of reference frames for description of the orbital and rotational motion of the Moon. We use a scalar-tensor theory of gravity depending on two parameters of the parametrized post-Newtonian (PPN) formalism and utilize the concepts of the relativistic resolutions on reference frames adopted by the International Astronomical Union in 2000. We assume that the solar system is iso...

Abstract: Compared to the doubly fed machine, the brushless doubly fed machine (BDFM) has high reliability and low maintenance requirements. First, by taking the negative conjugation of the control motor variables in rotor reference frame, a state-space model of BDFM is derived. It is then transformed into synchronous reference frame, called synchronous reference frame state-space model (SSSM)....

The presented system is a three-phase three-wire (3P–3W), seamless, capable, dual-stage PV power generation without battery storage for rural residential loads to ensure continuous supply during the daytime. This effortlessly shifts from grid-connected (GC) mode standalone (SA) when grid utility unavailable. During GC mode, voltage source converter (VSC) regulated by polynomial zero-attracting ...

This research work presents the comparison analysis of Shunt Active Filter (SAF) with Parallel Hybrid Active Filter (PHAF). The performances of SAF and PHAF have been analyzed with PI controllers based on Synchronous Reference Frame theory. In each case, simulation is carried out for three phase unbalanced non liner load conditions. The advantages of the designed system and the proposed current...

This paper presents a triple rotating coordinate transformed vector control method for dual three-phase permanent magnet (PM) machines. In the proposed scheme, variables are converted to three sets of ?? components directly, which 120° electric degrees different from each other. It omits complicated six-dimensional matrix and reduces computation greatly. The relationship with space (VSD) was ma...

Diesel Generator (DG) set based standalone supply systems are source of electricity in many parts of world. DG sets are backbone of supply in trains, hospitals, institutes, telecommunication towers etc. Because of huge demand of electricity for air-conditioning, lighting, toiletries, pantry demands in trains, the railways has been one of the big consumer of DG set based supply systems. Moreover...