Active three-phase rectifier systems usually cover a wide field of applications where high total power factor (99%+) and low mains current THDi (typ. <5%) are required. Passive three-phase rectifiers on contrary are characterized as highly efficient and robust whereas their power factor is limited to 0.9...0.95 due to rather high harmonic input current components (THDi up to 48%). This paper an...

Abstract:Today, one of the important issues of power quality (PQ) in power systems is the current harmonics. Increasing expansion of nonlinear loads at different parts of the electric network makes harmonic distortion flow through the network. This causes the network to have background voltage and current harmonic distortion and even affect on the PQ of linear load performance. Therefore, it is...

The progressive application of non-linear loads in distribution systems (DS) increases current harmonics flow in DS's apparatuses, especially distribution transformers (DTs). Since DTs' operating temperature rises due to the harmonics flow, their loading should be reduced such that the hot spot temperature (HST) is preserved under its permissible value. This means that DTs' available capacity i...

The harmonic oscillator in anti de Sitter space(AdS) is discussed. We consider the harmonic oscillator potential and then time independent Schrodinger equation in AdS space. Then we apply the supersymmetric Quantum Mechanics approach to solve our differential equation. In this paper we have solved Schrodinger equation for harmonic oscillator in AdS spacetime by supersymmetry approach. The shape...

Static synchronous compensators (STATCOMs) utilize multilevel converters due to the following: 1) lower harmonic injection into the power system; 2) decreased stress on the electronic components due to decreased voltages; and 3) lower switching losses. One disadvantage, however, is the increased likelihood of a switch failure due to the increased number of switches in a multilevel converter. A ...

This paper addresses a cause for false tripping of photovoltaic inverters with anti-islanding protection based on impedance measurement with inter-harmonic injection. Earlier discussions about tripping problems happening when several devices are doing the measurement at the same time are supplemented with a problem caused by inrush transients of nearby devices. A series of experiments was condu...

proper operations of transformer have several issues such as; preventing of unscheduled removal’s, increasing of reliability and continues supply of consumer demand. this result would be obtained that load and harmonic orders of sensitivity transformer at intervals appropriate for next hours and days is predicted to by selecting optimal utilization coefficient, reduction life of transformer is ...

Since the discovery of high-order harmonic generation (HHG) in solids1–3, much effort has been devoted to understand its mechanism and both inter- intraband transitions are known be essential1–10. However, affected by electronic structure a solid, how they contribute nonlinear carrier HHG remains an open question. Here we use mid-infrared laser pulses study CdSe CdS quantum dots, where confinem...

The ever increase of nonlinear loads in electric distribution networks causes many problems due to the high level of harmonic currents. This paper proposes a new technique for controlling a single phase shunt active power filter based on a selective compensation using the newly developed technique of harmonic control arrays. Simulation results confirm the appropriate selective harmonic compensa...

The equivalence between the natural minimization of energy in a dynamic system and an objective function characterizing combinatorial optimization problem offers promising approach to design dynamic-system-inspired computational models solvers for such problems. For instance, ground-state coupled electronic oscillators, under second-harmonic injection, can be directly mapped optimal solution ma...