abstract: in this paper a control scheme for grid-connected operation mode and the island state of distributed generation is presented. in normal conditions, every inverter dg system in micro-grids to supply a preset power, normally operate in a constant current control mode. when micro-grids removed from the network, dg inverter of each system must recognize the island and change position to v...

this paper presents the method of reducing torque ripple of brushless dc (bldc) motor. the commutation torque ripple is reduced by control of the dc link voltage during the commutation time. the magnitude of voltage and commutation time is estimated by a neural network and optimized with an optimization method named particle swarm optimization (pso) algorithm analysis. the goal of optimization ...

This paper includes modeling and simulation of 180 MW units of pumped storage power plant with Variable speed machines. In this method, voltage source inverters are used instead of traditional cyclo-converters. This paper aims to control the voltage source inverters and maintain DC voltage at a constant value. AC/ DC/ AC converter is used in system configuration structure in order to control an...

this paper presents a detailed small-signal and transient analysis of a full bridge pwm dc-dc converter designed for high voltage, high power applications using an average model. the derived model is implemented in a typical system and used to produce the small-signal and transient characteristics of the converter. results obtained in the analysis of the high voltage and high power design examp...

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...

microgrids are small-scale, low voltage (lv) power networks which employ renewable distribution energy resources (ders) with power electronic interfaces (peis). microgrids as single controlled units and active distribution networks require flexible control systems to ensure reliable and secure operation in different modes. these various operations of microgrid cause variations in voltage and fr...

In this study, a novel variable impedance control for a lower-limb rehabilitation robotic system using voltage control strategy is presented. The majority of existing control approaches are based on control torque strategy, which require the knowledge of robot dynamics as well as dynamic of patients. This requires the controller to overcome complex problems such as uncertainties and nonlinearit...