Improving the quality of electricity in local supply systems by managing operating mode bidirectional three-phase voltage converter

The Harmonics control of any inverters can be decided by the PWM incorporated for the switches. In recent years the carrier and reference modification based research is going on the inverter field. This paper suggests that the alteration of carriers and references of the three phase voltage source inverter enhance the ability to decrease the harmonic content.This enhanced realization deals with the carrier and reference modification arrangement for three phase voltage source inverter through amalgamating the boosted reference and random triangular carrier. The boosted reference is the addition of sine reference with injection of 1/3rd of reference amplitude (3fs) in the middle portion of the reference wave. i.e., [Formula: see text] to [Formula: see text] and [Formula: see text] to [Formula: see text] . The proposed PWM scheme use two carriers, one is Triangle wave and another one is inverted Triangle wave. The process of selecting the winning carrier among the two triangle carriers is purely based on the LFSR technique. The spectral quality of the induction motor drives has improved by the random carriers. The simulation and experimental values are proving the validity of the PWM method. The PWMs are generated by using parallel processing enabled FPGA processor.

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Identification of a synchronous generator parameters using recursive least squares and Kalman filter

CIENCIA EN DESARROLLO ◽

10.19053/01217488.v12.n1.2021.11779 ◽

2021 ◽

Vol 12 (1) ◽

pp. 13-21

Author(s):

Diego Alberto Bravo Montenegro ◽

Carlos Felipe Rengifo ◽

Cristian Giron ◽

Jhon Palechor

Keyword(s):

Kalman Filter ◽

Least Squares ◽

Synchronous Generator ◽

Measured Data ◽

Operating Conditions ◽

Recursive Least Squares ◽

Phase Voltage ◽

Three Phase ◽

Better Than

The comparison between recursive least squares (RLS) and Kalman filter (KF) is presented in this paper, both methods were adequate to estimate six parameters of a synchronous machine. The work focused on finding the operating conditions which the quality of the identification achieved with Kalman filter is better than recursive least squares. A linear model of the machine is used in order to considerate the currents and their derivatives as the system inputs while the three-phase voltage signals are the outputs. Furthermore two experiments with simulated and measured data were carried out, three operating scenarios and two variations of the algorithms respectively were considered. Despite the great similarity and good performance of both methods, it was found that Kalman filter slightly exceeded least squares due to the fact that it presented smaller oscillations in the estimated value of the parameters for any operating condition.

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Nonlinear Decoupling Control of DFIG

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.816-817.358 ◽

2013 ◽

Vol 816-817 ◽

pp. 358-362

Author(s):

Xiao Rong Zhu ◽

Hui Hui Zhang ◽

Peng Li

Keyword(s):

Feedback Linearization ◽

Reactive Power ◽

Decoupling Control ◽

Phase Voltage ◽

Nonlinear Mathematical Model ◽

Pwm Converter ◽

Three Phase ◽

Doubly Fed ◽

Small Capacity

DFIG (Double Fed Induction Generator) becomes a competitive wind power form due to it needs small capacity converter and the controllable of system efficiency and power factor. Aiming at back to back three-phase voltage-type PWM converter of the doubly-fed VSCF wind turbine, the nonlinear mathematical model of the controller of rotor side and network side is constructed, the strategy of feedback linearization of nonlinear control is proposed, the decoupling control of active and reactive power of DFIG is achieved. The simulation results indicate that: this control strategy has good dynamic characteristics, and the quality of power supply of DFIG is improved.

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DEVELOPMENT OF AN ELECTRONIC CIRCUIT FOR A SINGLE-PHASE VOLTAGE TO THREE-PHASE VOLTAGE CONVERTER

Modern Technologies and Scientific and Technological Progress ◽

10.36629/2686-9896-2020-1-107-108 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 107-108

Author(s):

Oleg Gorohov ◽

Aleksey Gurtovenko ◽

Yuriy Lipnin

Keyword(s):

Single Phase ◽

Electronic Circuit ◽

Phase Voltage ◽

Voltage Converter ◽

Three Phase

The searching of possible development of single-phase voltage to three-phase voltage converter and the need for this conversion

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Eliminating Three-Phase Voltage Unbalance by Using a Solid-State Transformer in Smart Power Supply Grids

Vestnik MEI ◽

10.24160/1993-6982-2021-4-67-75 ◽

2021 ◽

pp. 67-75

Author(s):

Boris A. Avdeev ◽

Keyword(s):

Solid State ◽

Power Supply ◽

Phase Voltage ◽

Solid State Transformer ◽

Smart Power ◽

Solid State Transformers ◽

Voltage Unbalance ◽

Input And Output ◽

Three Phase

The use of nonconventional power supplies featuring unstable quality of the electricity produced and fluctuations in the output power, on the one hand, and the availability of various consumers connected to power supply grids, on the other hand, are factors that give rise to phase unbalances in the grids. These circumstances complicate the operation of smart grids, especially in microgrids. One of possible ways to improve the quality of smart power supply grids is to use a three-stage solid-state transformer with galvanic isolation and two DC links, an arrangement that makes it possible to connect power supply sources and consumers, and to arrange backup storage of electricity in storage batteries. The aim of the study is to analyze the electric power quality at the output of a three-stage solid-state transformer powered by an unbalanced three-phase voltage source. The study was carried out by numerical modeling using the Matlab/Simulink software package. The modeling parameters are given, and the current and voltage waveforms at the solid-state transformer output are obtained. Phasors of the input and output voltages are constructed with expanding them into zero-, positive-, and negative sequence harmonic components. The harmonic distortion coefficients for current and voltage in each phase, and the voltage unbalance coefficients for the zero and negative sequences at the solid-state transformer input and output are determined using the method of symmetric components. It has been shown that by using solid-state transformers it becomes possible to obtain noticeably better quality of electric energy and eliminate the unbalance to the levels stipulated by the relevant state standard. It is shown that solid-state transformers are a promising technology as part of smart power supply grids, which opens the possibility to control and adjust power supply parameters, improve the power supply quality, distribute power flows between the sources and consumers, and integrate DC and AC grids of various voltage and power levels.

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Efficiency of the balancing devices to power quality improve

SHS Web of Conferences ◽

10.1051/shsconf/202110102012 ◽

2021 ◽

Vol 101 ◽

pp. 02012

Author(s):

Igor Naumov ◽

Sergey Podyachikh ◽

Dmitriy Ivanov

Keyword(s):

Electric Energy ◽

Operating Mode ◽

Electrical Equipment ◽

Electrical Network ◽

Phase System ◽

Electric Network ◽

Graphic Editor ◽

Three Phase ◽

Unbalanced Load

Violation of the symmetrical mode of operation of the electric network causes a deterioration in the quality of electric energy and significantly reduces the reliability of the functioning of electrical equipment and elements of the electric network. A mathematical model of an electrical network with a grounded neutral is proposed аnd a software package that allows us to evaluate the level of voltage asymmetry of a three-phase system depending on the changing unbalanced load was created. The simulation and calculation of the studied parameters for various combinations of loads and the technical means of balancing the operating mode of the electric network (the balancing device – BD) is carried out. Programs for the Matlab graphic editor are compiled and diagrams of changes in electricity quality indicators are constructed. A numerical analysis is carried out and recommendations are given to determine the most appropriate place for connecting the BD in the electrical network to improve the quality of electricity based on the calculation made.

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Microgrids Power Quality Enhancement Using Model Predictive Control

10.20944/preprints202101.0003.v1 ◽

2021 ◽

Author(s):

Félix Garcia-Torres ◽

Sergio Vazquez ◽

Isabel Moreno-Garcia ◽

Aurora Gil-de-Castro ◽

Pedro Roncero-Sánchez ◽

...

Keyword(s):

Model Predictive Control ◽

Power Quality ◽

Predictive Control ◽

Control Algorithm ◽

Pulse Width Modulation ◽

Phase Voltage ◽

Optimal Behavior ◽

Three Phase ◽

Current Systems

In this paper, the power quality of interconnected microgrids is managed using a Model Predictive Control (MPC) methodology which manipulates the power converters of the microgrids in order to achieve the requirements. The control algorithm is developed for the microgrids working modes: grid-connected, islanded and interconnected. The results and simulations are also applied to the transition between the different working modes. In order to show the potential of the control algorithm, a comparison study is carried out with classical Proportional-Integral Pulse Width Modulation (PI-PWM) based controllers. The proposed control algorithm not only improves the transient response in comparison with classical methods but also shows an optimal behavior in all the working modes, minimizing the harmonics content in current and voltage even with the presence of non-balanced and non-harmonic-free three-phase voltage and current systems

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