Victor Melo

• Professor at Federal University of Paraíba

The growth of DC microgrids has led to studies of wind energy systems in order to take advantage of this configuration. Thereupon, this paper aims to perform analysis and comparisons between the predictive current control (PCC) and the predictive flux and torque control (PTC) applied to the system with doubly-fed induction generator connected to a...

This paper discusses a Virtual Vector - Direct Torque Control (VV-DTC) technique that employs eight active voltage vectors to emulate the virtual voltage vectors used to control the electromagnetic torque and stator flux magnitudes of a three-neutral nine-phase induction machine drive system. In this configuration, the DTC strategy must take into a...

This paper discusses a Virtual Vector - Direct Torque Control (VV-DTC) strategy for an asymmetrical six-phase induction machine drive system that makes use of an isolated single neutral. The objectives of the proposed method are eliminating low-frequency $3^{rd}$ and $5^{th}$ current harmonic components during healthy operation and providing fa...

This paper proposes a reduced-computation-burden Finite Control Set - Model Predictive Control (FCS-MPC) applied to a dual-converter-based rectifier with a floating DC link. The main goal of this paper is providing a proof of concept of the discussed system employing the proposed FCS-MPC, highlighting its feasibility, simple multivariable control a...

In this paper, the performance of a shunt active power filter using direct power control based on the hysteresis method and model predictive control is discussed. Furthermore, an optimized vector selection is presented for model predictive control. This paper’s objective is to evaluate the processing time, reduction of harmonic components that woul...

This paper proposes a three-phase transformerless unified power quality conditioner (UPQC) based on a six-leg converter. It comprises three single-phase h-bridge converters, with one leg shared by both the shunt and series units per phase. The system provides grid power factor control with high power quality and supplies the load with a sinusoidal...

Predictive Current Control (PCC) has been widely applied in several applications. However, the literature has not discussed its use as a fault tolerance control algorithm in induction drive systems. In this way, this paper discusses the PCC method in two faulttolerant squirrel-cage induction machine drive systems operating under single-phase open-c...

This paper presents a parallel single-phase tothree-phase drive system, using two single-phase rectifiers.The rectifiers are not isolated from the grid by low-frequency transformers, so the reduction of the circulationcurrent is an important objective for the control strategy.Modulated Model Predictive Control regulates the gridcurrent and minimize...

In this paper, the performance of a shunt active power filter is discussed using the strategies of direct power control based on the hysteresis method and model predictive control. This paper's objective is to evaluate the reduction of harmonic components that would be injected into the electrical grid by a non-linear load, power semiconductor loss...

This paper presents the use of Finite Control Set - Model Predictive Control (FCS-MPC) applied to two topologies of multilevel converters with H-bridges connected in series to a three-phase converter operating as rectifiers. One of the topologies has a reduced number of controlled switches. Both configurations are analyzed for two different dc-link...

This paper presents a novel configuration to connect a three-phase doubly-fed induction generator (DFIG) to the dc microgrid. The proposed topology connects an uncontrolled con- verter and a full-controlled converter in series with the generator stator windings in an open-end winding (OEW) configuration. The full-controlled converter is connected t...

This article presents a novel system to connect a three-phase doubly fed induction generator (DFIG) to a dc-microgrid. The proposed topology is based on two three-phase half-controlled converters connected in series with the generator stator windings, in an open-end winding configuration. The converters operating principles, pulsewidth modulation,...

This paper proposes a single-phase to three-phase drive system consisting of two parallel single-phase rectifiers, one three-phase inverter and an induction motor. It uses two parallel rectifiers without low frequency transformers, thus the reduction of circulating current is an important objective in the control system. In this paper the Modulated...

This paper presents the use of the Modulated Model Predictive Control ( M2 PC) for three three-phase dual-converter based rectifiers, two of them with reduced switch-count. The control method performance is com-pared to that obtained with the Finite Control Set - Model Predictive Control (FCS-MPC). Additionally, a reduced computation burden method...

This paper presents a dual converter system to connect a three-phase doubly-fed induction generator (DFIG) to a dc microgrid. The proposed converter connects an uncontrolled converter and a full-controlled converter in series with the generator stator windings, in an open-end winding (OEW) configuration. The controlled converter is connected to an...

This paper presents a novel system to connect a three-phase doubly-fed induction generator (DFIG) to a dc-microgrid. The proposed system uses a three-leg rectifier at each side of the stator windings, in an open-end winding configuration. Usually, these legs are composed of insulated gate bipolar transistors (IGBTs). To reduce the number of control...

The behavior of climate elements can affect the generation of wind electricity. Small changes in wind speed can lead to high generation variability at wind power plants. In addition, the utilization of different temporal intervals within databases can yield different results due to climate dynamics. Consequently, using average values for a data ser...

In this paper a performance comparison between the methods Direct Power Control (DPC) and Predictive Torque Control (PTC) for a wind energy system that uses a doubly-fed induction generator is presented. Both methods are discussed and compared by means of steady-and transient-state simulation results for a 500-W generator. It will be shown that DPC...

This paper discusses Direct-torque-control(DTC)-based fault-tolerance strategies applied to three fault-tolerant induction motor drive systems when they operate under single-phase open-circuit fault. Despite the fact that these drive systems have already been discussed in the literature, the reported papers always make use of Field-oriented-control...

Este artigo apresenta a análise de uma topologia de conversão CA-CC-CA monofásico para trifásico. Este sistema é composto por dois retificadores multiníveis com transformadores em cascata e dois inversores trifásicos convencionais que alimentam um motor de indução com os enrolamentos em aberto. O modelo e a estratégia de controle do sistema são apr...

This paper proposes an unidirectional cascaded topology of power rectifier. It is composed of a three-leg cell with half-controlled legs series connected with one H-bridge cell per phase. The DC-links of the H-bridge cells operate with floating capacitors. The floating capacitor voltages regulation is solved by means of the common-mode voltage mani...

This paper presents a three-phase to singlephase six-leg converter for a wind energy conversion system based on Doubly-Fed Induction Generator (DFIG). The converter is composed of six legs and is divided in three parts: the grid-side converter (GSC), which is responsible for power factor and DC-link voltage controls, the stator-side converter (SSC)...

This paper presents a dual converter-based system in order to connect a three-phase doubly-fed induction generator (DFIG) to a dc-microgrid. The dual converter consists in connecting a three-leg rectifier at each side of the stator windings, in an open-end winding (OEW) configuration, adding up to two rectifiers and therefore six converter legs. Us...

This paper discusses the fault tolerance performance of two hybrid six-phase drive systems under single-phase open-circuit fault. The topologies are considered to be hybrid because each of the two three-phase groups of the six-phase machine is connected to a different type of converter. One group is connected to a two-level converter and the other...

This paper investigates a multilevel inverter composed of series/parallel-connected H-bridges. The presented structure can be used for applications in which the use of semiconductor switches with low voltage and low current ratings is intended. A comprehensive system model, an overall control strategy to adjust the output voltage with constant magn...

This paper investigates an ac-dc-ac multilevel power converter. The studied configuration is composed of two singlephase ac-dc-ac three-leg modules and series-connected H-bridges in the shared part of system. Because the proposed converter has shared legs between the input and output, it is employed in applications with same input and output freque...

In this work, an ac-dc-ac multilevel power converter for grid overvoltage is investigated. The developed configuration is composed of one single-phase ac-dc-ac three-leg module and two H-bridges, one of them connected in the shared part of the system to generate multilevel voltages at the input and output of the structure, and the other one connect...

Considering that so far all studies regarding multiphase drives fault tolerance performance have been carried out making use of conventional two-level inverters, this study discusses the fault tolerance performance of a six-phase drive system based on a dual inverter under single-, two-, or three-phase open-circuit fault. Aiming applications where...

This paper discusses the fault tolerance performance of two hybrid six-phase drive systems under single-phase open-circuit fault. The topologies are considered to be hybrid because each of the two three-phase groups of the six-phase machine is connected to a different type of converter. One group is connected to a two-level converter and the other...

This paper proposes four open-end nine-phase conversion systems with reduced number of controlled switches. For this to be achieved, a converter is shared among the three threephase groups that compose the machine. In addition, in order to reduce even more the number of controlled switches, three of the studied topologies with a shared converter ma...

This paper presents two hybrid six-phase machine drive systems. The topologies are considered to be hybrid because machine two three-phase groups are fed by different types of converters. The purpose of these topologies is to be alternative configurations, being midway between the conventional six-leg two-level (2L) inverter, composed of 12 switche...

This paper discusses a rectifier-inverter composed of two three-leg converters with equal and unequal DC-links voltages connected in series. The operation with equal DC-links voltages divides equally the voltages in each converter. On the other hand, the operation with unequal DC-links increases the number of voltage levels and contributes to reduc...

This paper presents two power-generation systems with a two-phase permanent-magnet (PM) synchronous machine associated with a rectifier with small number of controlled switches. The topologies are conceived with the purpose of converting wind energy into electrical energy for low-power applications, providing an enormous potential to be used in urb...

This paper discuss a rectifier-inverter composed of two three-leg converters with unequal DC-links connected in series. This increases the number of voltage levels and contributes to reduce harmonic distortion and losses. Several PWM strategies are discussed (Space-Vector, Level-Shifted and Hybrid Level-Shifted PWM). The balance of separated DC sou...

This paper presents four nine-phase drive systems. A nine-phase machine is connected to four converters in an open-end winding arrangement, with one of the converters being shared by all machine groups. Because of the shared converter, the structures are only applied for machines with α = 0°. A PWM strategy is discussed in order to reduce machine t...

This paper presents an AC drive system based on six-phase machine with three neutrals. The machine side converter has nine power legs and can be connected to the grid through one single DC-link or three isolated DC-links. Compared with the conventional back-To-back AC six-phase machine drive system, the proposed drive system permits reducing the DC...

This paper presents two six-phase open-end machine conversion systems. They are composed of three three-leg converters connected in series to a six-phase machine with open terminals, in an open-end winding connection. The converters use diodes to replace controlled switches, making the conversion system non-reversible and with a reduced number of c...

This paper presents an ac-dc-ac reversible nine-phase machine drive system. The grid side converter is composed of Y-connected single-phase bridges. As the machine is composed of three three-phase groups, a three-leg converters are connected separately to each group. The topology does not make use of input isolation transformers and reduces the pow...

This paper presents two machine drive system based on a six-phase machine (SPM) and three-leg converters. The machine is composed of two three-phase groups. For the first configuration, one of the groups is connected to a three-leg converter and the other is connected to other two three-leg converters in an open-end winding configuration (see Fig....

This paper presents two conversion systems based on the association of a six-phase machine (SPM) with an electrical grid by means of three- and single-phase converters. The machine is composed of two three-phase groups. One of them provides the power to the three-phase converter, and the other provides the power to the single-phase converters, in a...

This paper presents two energy conversion systems with two-phase permanent magnet (PM) machine and a rectifier with reduced number of controlled switches. The topologies are conceived with the purpose of converting wind energy into electrical energy (i.e., a wind energy conversion system (WECS)) for low power applications. Compared with some three-...

This paper presents an ac-dc-ac reversible six-phase machine drive system. It is composed of single-phase bridge converters connected in series in the grid side and single-phase bridge converters connected at the machine phase terminals. The proposed topology eliminates the input isolation transformers and reduces the power processed by converter s...

In this paper an Active Power Line Conditioner (APLC) is proposed based on a Modular Multilevel Cascade Converter (MMCC) - Double Star Chopper Cells (DSCC) topology. A higher-voltage, low-switching frequency IGBT converter is used to achieve harmonic minimization. Compared to the conventional APLC topology, the proposed approach employs lower DC-li...

This paper presents a topology based on the interconnection of single-phase H-bridge converters and a three-phase converter acting as a shunt active power filter. Contributions for the model, PWM approach and control strategies are presented to the studied converter. As compared to the conventional solution by using just H-bridges converters, the p...

This paper presents two conversion systems based on six-phase machine (SPM) and three-phase and single-phase series-connected converters without isolation transformers. Configuration 1 can be used with induction (IM) or permanent magnet synchronous (PMSM) machines, while configuration 2 is partially reversible and is more indicated for permanent ma...