Preface

"*If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.*" **Rene Descartes**

It is well known that MATLAB is a numerical computing environment that not only provides numerical calculations but also facilitates analytical calculations in most engineering applications of computers.

This is the first book in a three-volume series deploying MATLAB-based applications in almost every branch of science. The present textbook contains a collection of 20 high quality articles. In particular, the book consists of two sections, the first one is devoted to MATLAB applications in engineering and the second is devoted to image and signal processing. In what follows, we present a short summary focusing on the key concepts of each chapter.

**Section 1:** MATLAB applications in engineering

In **chapter 1** some script MATLAB codes and Simulink models about the PID structure applied to closed loop systems are presented. The closed loop control is used at several industrial applications. The most used control structure is the Proportional-Integral-Derivative (PID) controller. The MATLAB software offer several resources to analyzes dynamical systems and to tune the parameters of this kind of controller.

**Chapter 2** should give readers overall information about processing of rough data obtained from numeric simulator of electromagnetic field (EM). Many possibilities of visualization are be discussed with regard to practical use and with concrete examples from researcher's practice. Part of this chapter is dedicated to processing of multisource simulations, while the main purpose is to aid many researchers and students in the vast field of EM research. The authors present, in detail, their knowledge and tips which they have gathered through their studies and research activities.

In **chapter 3** the ability to simulate power converters is presented by using only Simulink. Traditionally two approaches are used to simulate power electronic systems:

#### XII Preface



In this chapter, the authors propose a method for simulating static converters with Simulink based on the variable topology approach where switching conditions of semiconductor are realized by switching functions.

**Chapter 4** deals with the faults diagnosis of a wound rotor synchronous machine (WRIM) by the principal component analysis (PCA) method. This work intends to show the strength of the PCA method in the faults diagnosis of systems, using the WRIM as the application device. To do this, the authors propose an accurate analytical model of the WRIM without or in the presence of faults. This model provides the matrix data of the several characteristic quantities of the machine. These data are included as input variables of the PCA method. Then, the authors present a complete approach of the PCA method based on the study of residues. Simulation results show the efficiency of the detection but require a good choice of the number of principal components. All of above work has been then implemented in the MATLAB software.

In **chapter 5** position, quasi-static behavior, velocity, acceleration and dynamic simulations are modelled and run by MATLAB/Simulink in order to analyze the dynamic and quasi-static behavior of the compliant MEMS amplifier.

**Chapter 6** proposes the SagWave software as a visual interactive capability to generated data for the dsPIC controller. The SagWave software can show the waveform and the phasor of the three-phase voltage. The simulation and experimental results have shown the simple control algorithm for generating the sag signal for testing. The SagWave software is based on MATLAB graphic user interface (GUI) and the hardware is based on dsPIC microcontroller.

In **chapter 7** the authors use the capabilities of MATLAB and its associated SimPower and Simulink toolboxes in the modeling and simulation of power electronics devices. Design and analysis steps were illustrated using MATLAB and Simulink as an engineering tool. The effectiveness of the SimPower toolbox was demonstrated via typical examples which lead the way for further investigation. The presented methodologies facilitate analysis, characterization, and design of efficient buck/boost converters. Researchers and practicing engineers should find practical value in the presented material. The chapter is self-contained in the sense of providing sufficient background and theoretical development on the subject.

X Preface

methods.



In this chapter, the authors propose a method for simulating static converters with Simulink based on the variable topology approach where switching conditions of

**Chapter 4** deals with the faults diagnosis of a wound rotor synchronous machine (WRIM) by the principal component analysis (PCA) method. This work intends to show the strength of the PCA method in the faults diagnosis of systems, using the WRIM as the application device. To do this, the authors propose an accurate analytical model of the WRIM without or in the presence of faults. This model provides the matrix data of the several characteristic quantities of the machine. These data are included as input variables of the PCA method. Then, the authors present a complete approach of the PCA method based on the study of residues. Simulation results show the efficiency of the detection but require a good choice of the number of principal components. All of above work has been then implemented in the MATLAB software.

In **chapter 5** position, quasi-static behavior, velocity, acceleration and dynamic simulations are modelled and run by MATLAB/Simulink in order to analyze the

**Chapter 6** proposes the SagWave software as a visual interactive capability to generated data for the dsPIC controller. The SagWave software can show the waveform and the phasor of the three-phase voltage. The simulation and experimental results have shown the simple control algorithm for generating the sag signal for testing. The SagWave software is based on MATLAB graphic user interface (GUI) and

In **chapter 7** the authors use the capabilities of MATLAB and its associated SimPower and Simulink toolboxes in the modeling and simulation of power electronics devices. Design and analysis steps were illustrated using MATLAB and Simulink as an engineering tool. The effectiveness of the SimPower toolbox was demonstrated via typical examples which lead the way for further investigation. The presented methodologies facilitate analysis, characterization, and design of efficient buck/boost converters. Researchers and practicing engineers should find practical value in the

dynamic and quasi-static behavior of the compliant MEMS amplifier.

the hardware is based on dsPIC microcontroller.

can be laborious as well as obtain switching conditions of the semiconductor.

semiconductor are realized by switching functions.

**Chapter 8** discusses Permanent Magnet Synchronous Motors (PMSM's). In particular, another solution has been presented to overcome the problems associated to DTC for PMSM in case of motor parameters variation and/or nonlinear operating conditions, which utilize speed FLC and an independent stator resistance estimator.

In **chapter 9** the authors deal with the problem of estimation the rotor position and speed in sensorless PMSM drive. At low speed range position estimation is particularly difficult due to the small value of the input and estimated signals, which are covered by measured noises and disturbances. Additional problem is to obtain high dynamic of the proposed drive system in the observer presence in control loop. The research was realized using MATLAB/Simulink.

In **chapter 10** it is explained how to simulate a digital differential relay using MATLAB. The following major sections are featured: a) General explanation about the differential protection algorithm, b) The problems that is aimed to be solved using the differential protection, c) General idea about the digital algorithms used to implement the differential protection, d) Explanation how to implement some of the digital algorithms using MATLAB.

**Chapter 11** develops a PH control strategy using MATLAB interfaced to NI acquisition card. The control strategy was developed using MATLAB Block Sets for fuzzy logic. To enhance the validity of this technique, a tuned Proportional-Integral-Derivative (PID) controller was developed and the results obtained were nowhere near those discussed in this chapter no matter how the fine tuning of the PID.

In **chapter 12** a detailed analysis and description of a line and cable model that is based on the principles of the Universal Line Model (ULM) is discussed. Moreover, a comprehensive description of the theoretical basis of ULM, phase domain line model is presented. The model structure being implemented in MATLAB is provided as well while the included application examples illustrate the model capabilities and provide benchmarks for further model development by readers interested in the subject.

**Chapter 13** presents a new approach for modeling the non-linear inductances by an analytic expression under the MATLAB/Simulink code. The current representation is based on the introducing point by point, by a Lookup Table bloc in Simulink, the values of its characteristic Φ(i) outcome deduced from the values of the magnetizing curve B-H and the geometric parameters of the corresponding portion of the magnetic circuit. This approach can solve many problems of modeling, simulation and optimization of the electrical networks and electric machines.

In **chapter 14** the principles of development virtual models in GUI MATLAB for chosen electrical machines and controlled drives are discussed. Moreover, it discusses methodology and results at design of a unified series of virtual models for electrical machines and drives, virtual models for analysis of dynamical properties of electrical machines, virtual models applied for synthesis of drive systems and experiences with utilization of virtual models.

#### **Section 2:** Image and Signal Processing

In **chapter 15** the authors introduced a novel computational method based on the calculation of the Moore-Penrose inverse of full rank rectangular matrix, with particular focus on problems arising in image processing. The motivation here relies on the problem of restoring blurry and noisy images via well developed mathematical methods and techniques based on the inverse procedures in order to obtain an approximation of the original image. By using the proposed algorithm, the resolution of the reconstructed image remains at a very high level, although the main advantage of the method was found on the computational load that has been decreased considerably compared to the other methods and techniques. The efficiency of the generalized inverse is evidenced by the presented simulation results in MATLAB.

**Chapter 16** presents the anatomy of Electromyography (EMG) signal, measurement, analysis, and it's processing. Moreover, the motion classification simulations are carried out, in order to evaluate classification performance of the human arm movements recognition based on K-Nearest Neighbor (K-NN) algorithm. The simulated data were generated from an EMG signal simulator. The results illustrate that the recognition using K-NN presents better results than artificial neural network in term of recognition accuracy. This chapter also presents the simulation of human arm motion in virtual reality to test the algorithm of EMG recognition. It can be concluded that, the virtual reality is useful to test the viability of designs before the implementation phase on a virtual reality prototype. It found that, MATLAB a convenient platform for development of computational algorithms, and with the visualization functions of MATLAB Ver.R2009a a reasonable amount of visualization techniques are available.

In **chapter 17** it is provided a comprehensive background and study for the effects of clock-jitter in the sampling-clocks of delta-sigma modulators. The study includes detailed analysis for the effects of clock-jitter on various waveforms and signals provided by different types of DACs used in delta-sigma modulators. Also, efficient MATLAB/Simulink models for additive errors induced by clock-jitter in delta-sigma modulators are shown so that to help designers characterize the sensitivities of various types of delta-sigma architectures to clock-jitter. The robustness of the adopted models is demonstrated through illustrative examples based on system-level simulations using MATLAB/Simulink.

**Chapter 18** Generally, a multiexponential transient signal is represented by a linear combination of exponentials of the form ( ) ( ) *<sup>k</sup> M k k S Ae n* , where M is the number of components, A*k* and k, respectively, correspond to the amplitude and realvalued decay rate constants of the kth component and n(τ) is the additive white Gaussian noise with variance <sup>2</sup> *<sup>n</sup>* . This chapter reports the development of a computationally efficient algorithm for high resolution estimates the signal parameters (M, A*k* and *<sup>k</sup>* ) using MATLAB.

XII Preface

utilization of virtual models.

techniques are available.

using MATLAB/Simulink.

**Section 2:** Image and Signal Processing

machines and drives, virtual models for analysis of dynamical properties of electrical machines, virtual models applied for synthesis of drive systems and experiences with

In **chapter 15** the authors introduced a novel computational method based on the calculation of the Moore-Penrose inverse of full rank rectangular matrix, with particular focus on problems arising in image processing. The motivation here relies on the problem of restoring blurry and noisy images via well developed mathematical methods and techniques based on the inverse procedures in order to obtain an approximation of the original image. By using the proposed algorithm, the resolution of the reconstructed image remains at a very high level, although the main advantage of the method was found on the computational load that has been decreased considerably compared to the other methods and techniques. The efficiency of the generalized inverse is evidenced by the presented simulation results in MATLAB.

**Chapter 16** presents the anatomy of Electromyography (EMG) signal, measurement, analysis, and it's processing. Moreover, the motion classification simulations are carried out, in order to evaluate classification performance of the human arm movements recognition based on K-Nearest Neighbor (K-NN) algorithm. The simulated data were generated from an EMG signal simulator. The results illustrate that the recognition using K-NN presents better results than artificial neural network in term of recognition accuracy. This chapter also presents the simulation of human arm motion in virtual reality to test the algorithm of EMG recognition. It can be concluded that, the virtual reality is useful to test the viability of designs before the implementation phase on a virtual reality prototype. It found that, MATLAB a convenient platform for development of computational algorithms, and with the visualization functions of MATLAB Ver.R2009a a reasonable amount of visualization

In **chapter 17** it is provided a comprehensive background and study for the effects of clock-jitter in the sampling-clocks of delta-sigma modulators. The study includes detailed analysis for the effects of clock-jitter on various waveforms and signals provided by different types of DACs used in delta-sigma modulators. Also, efficient MATLAB/Simulink models for additive errors induced by clock-jitter in delta-sigma modulators are shown so that to help designers characterize the sensitivities of various types of delta-sigma architectures to clock-jitter. The robustness of the adopted models is demonstrated through illustrative examples based on system-level simulations

**Chapter 18** Generally, a multiexponential transient signal is represented by a linear

number of components, A*k* and k, respectively, correspond to the amplitude and real-

*M k k S Ae n* 

, where M is the

combination of exponentials of the form ( ) ( ) *<sup>k</sup>*

The proposed algorithm involves modification of Gardner transform as well as a systematic approach for selecting the optimal truncation point which is required for real-time analysis. Furthermore, an integrated MATLAB--Labview software interface is proposed for real-time deployment of the algorithm. The analytical strength of MATLAB together with simplicity and user-friendly benefits of the National Instrument (NI) Labview design platforms are explored in developing an efficient, user-friendly algorithm for analysis and real-time implementation of multiexponential transient signal.

In **chapter 19** the basic fundamentals on digital Finite Impulse Response (FIR) Hilbert transformers are covered by reviewing the characteristics of analytic signals. The main connection between Hilbert transformers and half-band filters are highlighted. The methods to design low-complexity FIR filters, namely Frequency-Response Masking (FRM), Frequency Transformation (FT) and Piecewise Polynomial-Sinusoidal (PPS), as well as the Pipelining-Interleaving (PI) architecture, are introduced in a simplified and concise way. These methods are the cornerstone of the efficient techniques to design Hilbert transformers. Finally, with such background, an extensive revision of the aforementioned methods to design low--complexity efficient FIR Hilbert transformers is given, providing MATLAB routines for every method.

**Chapter 20** proposes a new method in order to detect craters on optical images by using MATLAB. Moreover, the chapter focuses on identification of craters in terms of its characteristics and detection of these visual features of the moon to determine a safe landing site for a lunar Lander. This is achieved by using autonomous crater detection on image using MATLAB image processing tools.

At this point, I would like to thank the authors for their great contribution in this series of scientific books regarding MATLAB applications in Sciences. Also, I thank the InTech team for their significant support during the preparation of this book.

> **Vasilios N. Katsikis**  Department of Mathematics, Technological Education Institute of Piraeus, Greece

**MATLAB Applications in Engineering** 
