Juan Dixon

Followers

Following

Co-authors

Public Views

Mehmet Hakan Hocaoglu

İstanbul Ticaret Üniversitesi

Leonard Bond

Iowa State University

Mohamad Tarnini

Beirut Arab University

P S Subramanyam

VIGNANA BHARATHI INSTITUTE OF TECHNOLOGY

Mario Ponce Silva

Centro Nacional de Investigación y Desarrollo Tecnológico

rai sankar

Andhra University

Sunil Singh

Govind Ballabh Pant Krishi evam Prodyogik Vishva Vidyalaya, Pantnagar, India

Georgios Konstantinou

The University of New South Wales

Unsw Josep Pou

The University of New South Wales

Luis Mariano Nodari

Instituto Federal de Educação, Ciência e Tecnologia de Santa Catarina

Interests

Uploads

Papers by Juan Dixon

Performance analysis of a power factor compensator which simultaneously eliminates line current harmonics

PESC `92 Record. 23rd Annual IEEE Power Electronics Specialists Conference

Download

A novel load current control method for a leading power factor voltage source PWM rectifier

IEEE Transactions on Power Electronics, 1994

Abstract-A novel PWM voltage source rectifier, controlled by the load dc current instead of the d... more

A New Mathematic Algorithm to Analyze Power Distribution Systems With Active Compensation and Nonlinear Loads

IEEE Transactions on Power Delivery, 2008

This paper presents a new procedure to analyze power distribution systems that energize nonlinear... more This paper presents a new procedure to analyze power distribution systems that energize nonlinear loads. The algorithm uses the singular values of the transfer matrix that relates the output variables and the system perturbation. The algorithm is especially developed to analyze the compensation performance of shunt and series active power filters. The algorithm is proved by simulation in a multibus industrial power distribution system and programmed in Matlab.

Download

A Three-Phase Controlled-Current PWM Converter with Leading Power Factor

IEEE Transactions on Industry Applications, 1987

Experimental tests performed on a three-phase bipolar- transistor controlled-current PWM power mo... more Experimental tests performed on a three-phase bipolar- transistor controlled-current PWM power modulator show that it can operate with near-sinusoidal currents at 60 Hz with a 360-degree power angle range. Because of its capability to operate with leading power factor and good waveform, the PWM converter is a promising alternative to the thyristor Graetz bridge. A theoretical method based on the concept of "local average" is presented.

Download

Characteristics of a Controlled-Current PWM Rectifier-Inverter Link

IEEE Transactions on Industry Applications, 1987

Two controlled-current pulsewidth-modulated (PWM) con- verters have been integrated into rectifie... more Two controlled-current pulsewidth-modulated (PWM) con- verters have been integrated into rectifier-inverter links of variable-speed ac motor drives. The authors focus on developing a mathematical model of the rectifier-inverter link and presenting experimental justification of the model. The characteristics of the rectifier-inverter system and the constraints imposed by the voltage feedback loop and dc link voltage are discussed. The rectifier-inverter system is made to drive a "self- controlled" synchronous motor, thus forming a system for which both the utility and the motor currents are near sinusoidal. The optimized power conversion capability of the motor is now matched by unity power factor operation on the rectifier side. Fast reversal from motoring to regenerative braking capability is demonstrated experimentally.

Download

An Integrated Controlled-Current PWM Rectifier Chopper Link for Sliding Mode Position Control

IEEE Transactions on Industry Applications, 1987

Position controllers must handle kinetic energy exchanges during acceleration and deceleration of... more Position controllers must handle kinetic energy exchanges during acceleration and deceleration of large inertias. Temporary buffer storage in capacitors is expensive. The system that can manage the power exchange with ease is the integrated controlled-current pulsewidth- modulated (PWM) rectifier/controlled-current PWM chopper link. Bidi- rectional power is accomplished by bidirectional current flow in the dc link for both modulators. The three-phase currents in the rectifier side are near sinusoidal in waveform at unity power factor. The performance of the system as a position controller in an environment of the sliding mode strategy is studied. The sliding mode strategy offers robust characteristics to the controller. m HE availability of fast high-power bipolar transistors, IGTO's, MOSFETs, and other semiconductor switches is ushering a new generation of rectifiers, inverters, and chop- pers based on pulsewidth modulation (PWM) principles. One promising version is the hysteresis current-controlled PWM modulators [11-[5]. Recently these have been configured into rectifier-inverter links to drive induction motors [6] and self- controlled synchronous motors [7]. As exemplified in the synchronous motor drive the technical capabilities are i) near- sinusoidal current waveforms at unity power factor at both the rectifier and inverter side, and ii) fast-response current and power reversibility at the dc link without the need of bidirectional power switches. Because of the need of current sensors, the hysteresis current-controlled PWM modulators are relatively expensive. Although the power ratings of the fast power switches are increasing progressively, they are modest compared to the thyristors. For these reasons the modulators will first find a market niche only in places where their technical excellence outweighs cost considerations. One market is likely to be in high-quality position controllers in the medium power range. As these position controllers accelerate their massive loads to high speeds and then decelerate them by regenerative braking, the fast bidirectional capability of these modulators can deliver and return the power directly to the power utility, thus

Download

Indirect current control of a unity power factor sinusoidal current boost type three-phase rectifier

IEEE Transactions on Industrial Electronics, 1988

The indirect current control scheme has evolved from the success of the hysteresis current contro... more The indirect current control scheme has evolved from the success of the hysteresis current controlled voltage regulated rectifier, which has been shown to be capable of: 1) unity and even leading power factor operation, 2) near sinusoidal current waveforms, and 3) bilateral power transfer without the need of bi-directional solid state power switches. The advance consists of replacing the inner hysteresis current feedback loop by the standard sinusoidal PWM control and in the process saving the cost of the current measuring transducers. The scheme is evaluated through tests on 1-KW size laboratory models and through digital simulations. A theory of the system dynamics is developed and stability boundaries are presented.

Download

Control system for three-phase active power filter which simultaneously compensates power factor and unbalanced loads

IEEE Transactions on Industrial Electronics, 1995

The effectiveness of an active power filter depends basically on three characteristics: (a) the m... more The effectiveness of an active power filter depends basically on three characteristics: (a) the modulation method used; (b) the design characteristics of the PWM modulator; and (c) the method implemented to generate the reference template. For the last characteristic there are many methods, most of them complicated and hence difficult to implement and adjust. In this paper, a new method,

A simple frequency-independent method for calculating the reactive and harmonic current in a nonlinear load

IEEE Transactions on Industrial Electronics, 1996

Abstruct-A basic criterion that determines the behavior of an active power filter is the method o... more Abstruct-A basic criterion that determines the behavior of an active power filter is the method of calculating the reference current. There are many ways of generating this reference, but the methods are generally complex and hard to tune. This paper describes a simple and effective method for calculating the reference current, necessary to feed a shunt active power filter to compensate the power factor and harmonic currents generated by a nonlinear load. Simulations and experimental results are presented, showing that the proposed circuit may operate at frequencies ranging from 40 to 65 Hz without adjustment.

Download

Energy-management system for a hybrid electric vehicle, using ultracapacitors and neural networks

IEEE Transactions on Industrial Electronics, 2006

A highly efficient energy management system for hybrid electric vehicles (HEV), using neural netw... more A highly efficient energy management system for hybrid electric vehicles (HEV), using neural networks (NN), was developed and tested. The system minimizes the energy requirement of the vehicle and can work with different primary power sources like fuel-cells, microturbines, zinc-air batteries or other supply with poor ability to recover energy from regenerative braking, or with scarce power capacity for fast acceleration. The experimental HEV uses lead-acid batteries, an ultracapacitor bank, and a brushless dc motor with a nominal power of 32 kW, and a peak power of 53 kW. The control system, based on a DSP, measures and stores the following parameters: primary source voltage, car speed, instantaneous currents in both terminals (primary source and ultracapacitor), and actual voltage of the ultracapacitor. The increase in range with ultracapacitors has been around 5.3 % in city tests, compared when only lead acid batteries are used, but when optimal control with NN is used, this figure increases to 8.9 %. The car used for this experiment is a Chevrolet LUV truck, similar in shape and size to a Chevrolet S-10, which was converted to an electric vehicle at the Universidad Católica de Chile. Numerous experimental tests under different conditions are compared and discussed.

Download

Transient Tests on a Voltage-Regulated Controlled-Current PWM Converter

IEEE Transactions on Industrial Electronics, 1987

The controlled-current PWM converter has the capability of delivering near sinusoidal current wav... more The controlled-current PWM converter has the capability of delivering near sinusoidal current waveforms with unity and even leading power factors. This paper describes its transient characteristics when operated with a simple proportional feedback control to ensure regulated dc voltage output. Experimental tests show that it has fast step response and that it survives abnormal operational conditions such as brown-outs and loss of a single phase. The mathematical model of the system has been derived and the excellent agreement between experimental results with mathematical simulations indicate that the model can be used with confidence.

Download

Improving passive filter compensation performance with active techniques

IEEE Transactions on Industrial Electronics, 2003

This paper presents the performance analysis of a hybrid filter composed of passive and active fi... more This paper presents the performance analysis of a hybrid filter composed of passive and active filters connected in series. The analysis is done by evaluating the influence of passive filter parameters variations and the effects that different active power filter's gain have in the compensation performance of the hybrid scheme. The compensation performance is quantified by evaluating the attenuation factor in a power distribution system energizing high-power nonlinear loads compensated with passive filters and then improved with the connection of a series active power filter. Finally, compensation characteristics of the hybrid topology are tested on a 10-kVA experimental setup.

Download

Sensorless Control for a Switched Reluctance Wind Generator, Based on Current Slopes and Neural Networks

IEEE Transactions on Industrial Electronics, 2009

In this paper, the analysis, design, and implementation of a novel rotor position estimator for t... more In this paper, the analysis, design, and implementation of a novel rotor position estimator for the control of variable-speed switched reluctance generators (SRGs) are presented. The rotor position is obtained using the unsaturated instantaneous inductance. This unsaturated inductance is estimated calculating the slope of the phase current and using a reducedsize neural network (NN) whose inputs are the average current and the saturated inductance. The proposed estimator requires less processing time than traditional methods and can be fully implemented using a low-cost DSP with very few additional analog/ digital components. The rotor position estimator presented in this paper can be applied to a wind energy conversion system where the SRG is used as a variable-speed generator. This application is currently being studied because the SRG has well-known advantages such as robustness, low manufacturing cost, and good sizeto-power ratio. Simulation and experimental results are presented using a 2.5-kW 8/6-SRG prototype.

Download

Static Var Compensator and Active Power Filter With Power Injection Capability, Using 27-Level Inverters and Photovoltaic Cells

IEEE Transactions on Industrial Electronics, 2009

An active power filter and static var compensator with active power generation capability has bee... more An active power filter and static var compensator with active power generation capability has been implemented using a 27-level inverter. Each phase of this inverter is composed of three "H" bridges, all of them connected to the same dc link and their outputs connected through output transformers scaled in the power of three. The filter can compensate load currents with a high harmonic content and a low power factor, resulting in sinusoidal currents from the source. To take advantage of this compensator, the dc link, instead of a capacitor, uses a battery pack, which is charged from a photovoltaic array connected to the batteries through a maximum power point tracker. This combined topology make it possible to produce active power and even to feed the loads during prolonged voltage outages. Simulation results for this application are shown, and some experiments with a 3-kVA device are displayed.

Download

Asymmetrical Multilevel Inverter for Traction Drives Using Only One DC Supply

IEEE Transactions on Vehicular Technology, 2010

The main advantage of asymmetrical multilevel inverters is the optimization of levels with a mini... more The main advantage of asymmetrical multilevel inverters is the optimization of levels with a minimum number of power supplies. However, this optimized multilevel system still needs a large number of isolated and floating dc supplies, which makes these converters complicated to implement in electric vehicles (EVs), because the system will require many independent battery packs. In this paper, a very simple scheme, based on a small and cheap high-frequency link (HFL), allows the utilization of only one power supply for the complete multilevel inverter drive, with an inherent regulation of the voltages supplied among the H-bridges. It also allows voltage control with the full number of levels if the dc source is of a variable voltage characteristic. This paper is focused on a 27-level asymmetric inverter, but the strategy, using only one power supply, can be applied to converters with any number of levels. In particular, an asymmetrical 27-level converter needs nine isolated power supplies, and the proposed system reduces these nine sources to only one: the battery car. The topology also permits full regenerative braking working as a three-level converter. The proposed system is intended for application in EVs from power ratings up to 150 kW. Simulations and experimental results show the feasibility to implement this "one-source" multilevel system.

Download

Cascaded Nine-Level Inverter for Hybrid-Series Active Power Filter, Using Industrial Controller

IEEE Transactions on Industrial Electronics, 2010

An industrial controller, specifically designed for two-and three-level converters, was adapted t... more An industrial controller, specifically designed for two-and three-level converters, was adapted to work on an asymmetrical nine-level active power filter (APF). The controller is now able to make all required tasks for the correct operation of the APF, such as current-harmonic elimination and removal of high-frequency noise. The low switching-frequency operation of the nine-level converter was an important advantage in the application of the industrial controller. In addition, with the nine-level filter, switching losses were significantly reduced. The filter was designed to work as voltage source and operates as harmonic isolator, improving the filtering characteristics of the passive filter. The control strategy for detecting current harmonics is based on the "p−q theory" and the phase-tracking system in a synchronous reference frame phase-locked loop. The dc-link voltage control is analyzed together with the effect of controller gain and delay time in the system's stability. Simulations for this application are displayed and experiments in a 1-kVA prototype, using the aforementioned industrial controller, were tested, validating the effectiveness of this new application.

Download

PWM Method to Eliminate Power Sources in a Nonredundant 27-Level Inverter for Machine Drive Applications

IEEE Transactions on Industrial Electronics, 2009

A nonredundant three-stage 27-level inverter using "H" converters is analyzed for medium-and high... more A nonredundant three-stage 27-level inverter using "H" converters is analyzed for medium-and high-power machine drive applications. The main advantage of this converter is the optimization of levels with a minimum number of semiconductors. However, the system needs six bidirectional and isolated power supplies and three more unidirectional if the machine is not using regenerative braking. In this paper, these nine power supplies are reduced to only four, all of them unidirectional, using three strategies: 1) the utilization of independent and isolated windings for each phase of the motor; 2) the utilization of independent input transformers; and 3) the most important of them, the application of special pulsewidth modulation (PWM) strategies on the 27-level converter, to keep positive average power at the medium power bridges and zero average power at the low-power bridges. The generation of this PWM and control of this multiconverter was implemented using DSP controllers, which give flexibility to the system.

Download

High-Frequency Link: A Solution for Using Only One DC Source in Asymmetric Cascaded Multilevel Inverters

IEEE Transactions on Industrial Electronics, 2011

Download

High-level multistep inverter optimization using a minimum number of power transistors

IEEE Transactions on Power Electronics, 2006

Multilevel inverters with a large number of steps (more than 50 levels) can generate high quality... more Multilevel inverters with a large number of steps (more than 50 levels) can generate high quality voltage waveforms, good enough to be considered as suitable voltage template generators. Many levels or steps can follow a voltage reference with accuracy, and with the advantage that the generated voltage can be modulated in amplitude (AM) instead than PWM. The main disadvantage of this type of topology is the large number of power supplies and semiconductors required to obtain these multi-step voltage waveforms. This paper is focussed in minimizing the number of power supplies and semiconductors (transistors or GTOs) for a given number of levels. Different combinations of topologies are presented, and the corresponding mathematical relations have been derived. The paper shows optimized curves to obtain the relation between minimum number of power semiconductors required for a given number of levels. Experimental results obtained from an optimised prototype, capable to generate 81 levels of voltage with only four power supplies and sixteen transistors per phase are shown.

Download

Design, Implementation and Construction of a Multilevel Inverter for Robot Arm Drive, by Means of a Brushless Motor

— Modern industrial processes depend on the technology for automation, especially in robotics and... more — Modern industrial processes depend on the technology for automation, especially in robotics and position control. Electrical Machinery used for these purposes are varied, nevertheless, permanent magnet electric machines have better performance thanks to their high power density and low inertia. On the other hand, the most popular technique used in controlling position is the PWM drive. In this work the position control of a permanent magnet machine driven by a multilevel configuration, taking advantage of its benefits is presented. This article presents a first step of the total workforce, showing the state of the art and the overall structure of that work.

Performance analysis of a power factor compensator which simultaneously eliminates line current harmonics

PESC `92 Record. 23rd Annual IEEE Power Electronics Specialists Conference

Download

A novel load current control method for a leading power factor voltage source PWM rectifier

IEEE Transactions on Power Electronics, 1994

Abstract-A novel PWM voltage source rectifier, controlled by the load dc current instead of the d... more

A New Mathematic Algorithm to Analyze Power Distribution Systems With Active Compensation and Nonlinear Loads

IEEE Transactions on Power Delivery, 2008

Download

A Three-Phase Controlled-Current PWM Converter with Leading Power Factor

IEEE Transactions on Industry Applications, 1987

Download