Unbalanced voltage

This paper proposes an effective controller for grid connected wind turbine based permanent magnet synchronous machine for improving unbalanced voltages. In this paper, we proposed a comparative analysis under different controllers like PI and Fuzzy Controller to PMSG system. A control structure is designed based on the positive sequence reference signals.

7p phanngocminhtam 14-09-2021 13 1   Download

The proposed scheme is verified by the simulation results which show that three-phase split-capacitor inverter gives a low total harmonic distortion (THD) for the load voltages under the balanced or unbalanced nonlinear load conditions.

12p cothumenhmong11 06-05-2021 24 1   Download

This paper presents modified Stator Fed Oriented Control (SFOC)for Doubly Fed Induction Generator (DFIG) in wind turbines during grid unbalance,and improves stability by using Notch filter to eliminate second order harmonic components.The proposed schemes apply multiple PI controllers with Fuzzy and anti-windup (PI-F) to obtain commanded rotor currents and also introduce extra commanded values for rotor currents.

5p angicungduoc9 04-01-2021 6 1   Download

A novel control scheme for power converters of doubly-fed induction generator (DFIG) wind turbine system has been proposed to mitigate the current oscillations due to grid voltage unbalance. With this proposed scheme, the current controller is designed in the synchronous reference frame and composed of a proportional integral (PI) controller and a repetitive controller. Thus, the proposed controller gives better performance of the DFIG wind turbine system, compared with the existing dual PI one.

10p kequaidan8 02-11-2020 16 1   Download

In this research, an enhanced control scheme for the permanent-magnet synchronous generator (PMSG) wind turbines under grid voltage fault condition is introduced. The machine-side converter (MSC) controls the DC-link voltage; however, this voltage value can be still increased during the grid fault.

10p vimax2711 27-03-2020 36 0   Download

This paper presents a new method to dynamically regulate the input line-to-line voltages to ensure the symmetry of each other. It is realized through the instantaneous correction of the bias values in the course of sampling, and the correction is embodied in the modified control algorithm.

9p vivalletta2711 11-01-2020 18 1   Download

Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs). By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented.

9p kequaidan1 16-11-2019 23 0   Download

This paper proposes an enhanced nonlinear control technique based on a combination of feedback linearization (FBL) and resonant regulator as tracking controllers for the doublyfed induction generator (DFIG) wind turbine system under unbalanced grid voltage. A nonlinear model of DFIG wind turbine system with the rotor-side converter (RSC) is firstly linearized, not by small signal analysis.

11p vicolor2711 15-07-2019 16 1   Download

The Altivar 71 range of variable speed drives is able to respond to the most exacting requirements thanks to its different types of motor control and numerous onboard functions.

215p ducthaobg83 25-09-2012 90 8   Download

In this contribution several topics concerning magnetic fields and overhead medium voltage power lines are reviewed: simple formulation to assess the magnetic field (MF) level; characterization of magnetic fields generated by typical three-phase and one-phase primary distribution lines, with balanced and unbalanced current; and main mitigation techniques, analysed in relation with typical reduction level obtained. Additional data concerning cost and performance of different solutions are also provided....

31p powersystem 06-07-2010 123 8   Download