A switching fuzzy controller for induction motor with self-tuning capability

Fuzzy-logic based controllers have been recently proposed to implement vector control methods in induction motors. This paper presents a new switching self-tuning type of fuzzy controller aimed at obtaining a satisfactory performance (rise time and overshoot) in the motor response. Two fuzzy controllers, a PI-like fuzzy controller and a PD-like fuzzy controller are applied in different regions of the control space. Their responses are combined by another fuzzy inference machine which divides the control surface in a fuzzy way. Also a simple adaptive fuzzy system have been used to tune the proposed controller to provide a simple way to redefine the controller and obtain a better control action. Simulation results show that this scheme has the ability to improve the transient and steady state performance of the controlled system from the simple PD-like and PI-like fuzy controllers. The scheme has been implemented using a DSP and the simulation results have been experimentally validate

New space vector modulation algorithms applied to multilevel converters with balanced DC-link voltage

This work presents a survey of new space vector modulation algorithms for high power voltage source multilevel converters. These techniques provide the nearest switching vectors sequence to the reference vector and calculates the on-state durations of the respective switching state vectors without involving trigonometric functions, look-up tables or coordinate system transformations which increase the computational load corresponding to the modulation of a multilevel converter. These algorithms drastically reduce the computational load maintained permitting the on-line computation of the switching sequence and the on-state durations of the respective switching state vectors. The on-state durations are reduced to a simple addition. In addition, the low computational cost of the proposed methods is always the same and it is independent of the number of levels of the converter. The algorithms have been satisfactorily implemented in very low-cost microcontrollers.Ministerio de Ciencia y Tecnología DPI 2001-308

The Essential Role and the Continuous Evolution of Modulation Techniques for Voltage-Source Inverters in the Past, Present, and Future Power Electronics

The cost reduction of power-electronic devices, the increase in their reliability, efficiency, and power capability, and lower development times, together with more demanding application requirements, has driven the development of several new inverter topologies recently introduced in the industry, particularly medium-voltage converters. New more complex inverter topologies and new application fields come along with additional control challenges, such as voltage imbalances, power-quality issues, higher efficiency needs, and fault-tolerant operation, which necessarily requires the parallel development of modulation schemes. Therefore, recently, there have been significant advances in the field of modulation of dc/ac converters, which conceptually has been dominated during the last several decades almost exclusively by classic pulse-width modulation (PWM) methods. This paper aims to concentrate and discuss the latest developments on this exciting technology, to provide insight on where the state-of-the-art stands today, and analyze the trends and challenges driving its future

CD-ROM multimedia como método de ayuda a la enseñanza teórica de un DSP

En este documento se presenta un libro electrónico interactivo realizado en el Departamento de Ingeniería Electrónica de la Escuela Superior de Ingenieros de Sevilla. El material didáctico servirá de complemento a las tradicionales lecciones magistrales asociadas a la asignatura “Complemento de Sistemas Electrónicos Digitales”, obligatoria de tercer curso de Ingeniero de Telecomunicación

An efficient ordering algorithm to improve sparse vector methods

This paper presents a new node ordering algorithm to enhance sparse vector methods. The proposed technique locally minimizes the number of non-zero elements of the inverse of the table of factors. It uses the cardinality of the set of nodes which precede each node in the path graph as a tie-break criterion in the minimum degree elimination process. Test results are included showing that the method performs better than previously published methods.IEEE Power & Energy Societ

Space Vector Modulation Techniques for Multilevel Converters – a survey

This paper presents a survey of most recent, simple and efficient Space Vector Modulation algorithms for multilevel converters. These algorithms avoid trigonometric and other complex operations, leading to more simple and cost efficient implementations. They can be applied to multilevel topologies and present freedom degrees that can be Exploited in order to optimize system parameters in the system like: capacitors voltages balancing or voltage/current ripples. Experimental results are presented to show the good performance of the algorithms

Controladores digitales estocásticos

En este artículo se presenta la realización de controladores clásicos basados en el procesamiento lógico estocástico. Se aporta una descripción de las operaciones aritméticas básicas -suma, resta, multiplicación e integración. EI objetivo de esta arquitectura es proporcionar un conjunto de circuitos simples que permitan realizar estas operaciones con circuitos digitales simples. Como resultado de ello se pueden sintetizar controladores empleando dispositivos lógicos programables (FPGA). EI circuito desarrollado es aplicado a un sistema real con el uso de un convertidor analógico estocástico (ASC)

Multi-Processor Architectures for Solving Sparse Linear Systems. Application to the Load Flow Problem

IFAC SYMPOSIUM ON COMPONENTS,INSTRUMENTS AND TECHNIQUES FOR LOW COST AUTOMATION AND APPLICATIONS.1986 (.1986.VALENCIA)Three heuristic algorithms for solving a cluster problem associated with the tearing of a symmetric matrix are presented. Based on these partitioning procedures, a method for the parallel solution of the fast decoupled load flow has been developed, although it is also suitable for the parallel solution of any linear equations system. Experimental results of applying such algorithms on several test systems have been obtained using a multiprocessor architecture