in this paper, a new cascaded multilevel inverter by capability of increasing the number of output voltage levels with reduced number of power switches is proposed. the proposed topology consists of series connection of a number of proposed basic multilevel units. in order to generate all voltage levels at the output, five different algorithms are proposed to determine the magnitude of dc volta...

this paper presents the new topology of three phase on line uninterruptible power supply (ups) by employing t-source inverter (tsi) with maximum constant boost pulse width modulation (pwm) control and the results are compared with the conventional uninterruptible power supply (ups). the conventional ups consists of voltage source inverter (vsi) with step up transformer or dc-dc booster which de...

This article proposed a novel topology of dynamic voltage regulator using transformer and PWM multi-level AC/AC converter. In this paper for finding the best value of duty ratio for switches to minimize the THD, the GA algorithm has been used and THD output voltage is assumed to be fitness function. The proposed voltage regulator employs multi-level AC/AC converter to generate compensation volt...

Finding the collapse susceptible portion of a power system is one of the purposes of voltage stability analysis. This part which is a voltage control area is called the voltage weak area. Determining the weak area and adjecent voltage control areas has special importance in the improvement of voltage stability. Designing an on-line corrective control requires the voltage weak area to be determi...

Finding the collapse susceptible portion of a power system is one of the purposes of voltage stability analysis. This part which is a voltage control area is called the voltage weak area. Determining the weak area and adjecent voltage control areas has special importance in the improvement of voltage stability. Designing an on-line corrective control requires the voltage weak area to be determi...

today, with attention to increase in sensitive electrical equipments application in distribution networks and their susceptibility to the power quality deficiencies, the protection necessity of sensitive loads against undesirable effects of these disturbances are in focus. so, in this paper voltage sag deficiency and dynamic voltage restorer (dvr) would be introduced as the most prevalent power...

This paper suggests a new control method to modify the virtual impedance performance in unbalanced conditions. The proposed method compensates the voltage drop that occurred due to the virtual impedance and adjusts the voltage of the point of common coupling at a desirable level. To compensate the voltage drop, the reference voltage in the droop control varies according to the proposed algorith...

this paper describes how multi-agent system technology can be used as the underpinning platform for voltage control in power systems. in this study, some facts (flexible ac transmission systems) devices are properly designed to coordinate their decisions and actions in order to provide a coordinated secondary voltage control mechanism based on multi-agent theory. each device here is modeled as ...