In this paper an attempt has beenmade to investigate the transient stability enhancement of both SMIB and Multi-machine system using UPFC controller tuned by Particle Swarm Optimization. Power injection modelfor a series voltage source of UPFC has been implemented to replace UPFC by equivalent admittance. The admittance matrix of the power system is then modified according to the power injectio...

This paper presents a methodology to apply a novel space vector pulse width modulation control for three phase Z-source inverter. The space vector modulation for the conventional voltage source inverter is modified so that the additional shoot-through states are inserted within the zero states. So zero voltage time period is diminished for generating a shoot-through time, and active states are ...

The paper proposes a method for the rotor speed and position estimation of permanent magnet synchronous motors, applicable in a wide speed range including standstill. A modified voltage model is used at high speeds, and it is combined with a high-frequency signal injection technique at low speeds. The fast dynamic response of the voltage model is thus augmented with the steady-state accuracy of...

A main control task in photovoltaic (PV) power generation is the output voltage stabilization under varying irradiation or load changes. Taking into account the input voltage nonlinear dependence from the input current of a PV system as well as the nonlinear dynamics of a DC/DC boost converter, an appropriate PI controller is proposed. To this end, the passivity-based control analysis as it has...

earliness and drought escape are as a primary strategy for plant adaptation in regions that plants are subjected to terminal drought stress. plants react to drought through morphological changes and alteration in physiological behavior. accordingly, two separate experiments to assess the response of yield and morphophysiological characteristics of earliness chickpea genotypes to drought stress ...

study area is located in west of iran with relatively rough topography. lithologic units in the region belong from jurassic and cretaccous till recent era. the study area of the alvand mountain region is related to the tectonic zone of the sanandaj-sirjan region and the area dominant neo-tectonic regime appears to be compressional-extensional type. one of the identification tools to find out th...

Purpose – The aim of this paper is to improve and adapt cascaded multilevel converters for electric vehicles (EVs) to have all the advantages of these converters and to eliminate its limitations in the use of EVs applications. Specifically, the purpose is to use only a single power source (battery pack, fuel cell, etc.) and generate a higher power-quality than regular multilevel converters. Des...

abstract the effect of land use type on soil functioning within an ecosystem can be assessed and monitored using soil quality attributes. such studies, which are carried out to create a balance between the biological production and the maintenance and improvement of land resource quality, provide a framework for land degradation control and also for identification of sustainable management. in ...

Over the last few years, the problem of voltage stability has received a lot of attraction from the power system community. This type of stability is now a major concern for utilities in both planning and operating conditions. Both static and dynamic aspects of the problem have been discussed and investigated by the researchers. The present paper concentrates on a Voltage Stability Analysis fun...

Voltage collapse and blackout can occur in an electric power system when load powers vary so that the system loses stability in a saddle node bifurcation. We propose new iterative and direct methods to compute load powers a t which bifurcation occurs and which are locally closest to the current operating load powers. The distance in load power parameter space to this locally closest bifurcation...