# I. Introduction atrix converters are capable of AC/AC direct power conversion. It does not have any dc-link circuit and does not need any large energy storage elements. The key element of a Matrix Converter is the fully controlled four quadrant bidirectional switch, which allows high frequency operation. The matrix converter consists of 9 bi-directional switches that allow any output phase to be connected to any input phase. space-vector modulation technique is used in Matrix converter modulation technique. The SVM technique was adapted for the matrix converter by employing a basic concept of indirect modulation using a fictitious DC bus, then dividing the converter into a rectification stage and an inversion stage. Furthermore, this modulation technique allows simplifying a converter model, making it easier to control the converter under imbalanced and distorted power supply conditions. BY using this technique Matrix converter generate variable frequency. # II. Literature Review This part of the thesis consists of the details of modulation technique and the switching topology of matrix converter. The working principal of most of the technique will also be explained. The main technique those are used for analysis Matrix converter are:- # Space vector modulation: Space vector modulation is an algorithm for the control of PULSE WIDTH MODULATION (PWM). It is used for the creation of ac Author: Faculty of Engineering, American International University-Bangladesh (AIUB). e-mail: anubhabsarkar578@gmail.com wave forms. It is a general technique for any threephase load, although it has been developed for motor control. Space vector pulse width modulation is applied to output voltage and input current control. This method is an advantage because of increased flexibility in the choice of switching vector for both input current and output voltage control. It can yield useful advantage under unbalanced conditions. The three phase variables are expressed in space vectors. For a sufficiently small time interval, the reference voltage vector can be approximated by a set of stationary vectors generated by a matrix converter. The modulation process thus required consists of two main parts: selection of the switching vectors and computation of the vector time intervals. SVPWM refers to a special switching sequence of the upper three power transistors of a three-phase power inverter. It has been shown to generate less harmonic distortion in the output voltages and or currents applied to the phases of an AC motor and to provide more efficient use of supply voltage. There are two possible vectors called zero vector and Active vector. # Modulation technique of Matrix converter: Matrix Converter operation can be explained in more general terms using a space vector approach. For operation of the Matrix Converter one and only one switch in each output phase must be conducting. This leads to twenty seven possible switching combinations for the Matrix Converter. By applying Equations 1 and .2 to determine the output voltage and input current vectors respectively, the magnitude and phase of these vectors for all possible combinations are needed. To find current and voltage modulation index power balance condition can be used. With balanced output load current condition such as, ?? (????) ????? = (qVim?3) cos(?ot)(1)?? (0??) ?????? = 2 3 (v1o + av2o + ?? 2 v3o )(2) Where, a = ?? ?? 2?? 3 The vector ?? (0??) ?????? has a constant length of qVin?3 and it is rotating at frequency ?o. The basis of the space vector modulation technique is that the possible output voltages for the converter can be expressed in the same form as Equation 2 The reverse blocking capability is a weak of the early IGBT technology . The advantage is that it is possible to independency control the direction of the current. # III. Designing of Simulink Models and Outputs This part is carrying the whole design of Space vector modulation and Matrix converter models and analysis their outputs. In figure 3 3? supply is provided where the frequency is used 60Hz. This fundamental frequency is modulated by SVM technique. In this technique high switching frequency is needed for triggering. In figure 4 common ammeter bidirectional switch is used where the modulated signal is used as input signal. After finishing all the switching combination inside the SVM symmetric switching part the desired frequency will be gotten. # IV. Conclusion The conversion from ac to ac is quite difficult. but matrix converter makes it simple and easy. It has appeared as an alternative solution for adjustable speed AC drive applications. This thesis presented easier References Références Referencias methods for implementing complex switching strategies, studying and mitigating the effects of unbalance, and topological changes to increase the performance indices. The thesis also suggests modulation techniques to eliminate the common mode voltage and a new direct torque control procedure for controlling an induction motor fed by the modified matrix converter topology. The work also introduces a simple carrier based modulation technique, termed as the SVM technique, as an alternative way of implementing the space PWM technique for the matrix converter. Based on the analysis carried out on the original SV PWM technique, the thesis proposes a modified control algorithm. This modified algorithm reduces the input current harmonic distortion without affecting the output side performance. 1![. At each sampling instant, the position of ?? (0??) ?????? is compared with the possible vectors and the desired output voltage is synthesized by time averaging (within the switching interval) between M Space vector modulation 2. Modulation technique of Matrix converter 3. Matrix Converter Switching States 4. Topologies of Bi-directional Switches Year 2016 F © 2016 Global Journals Inc. (US) adjacent vectors to give the correct mean voltage. For a conventional DC link inverter this process is very simple because there are only eight possible switching. The situation with a Matrix Converter is more complex as there are twenty seven possible switching states and the input voltages are time varying. Matrix Converter Switching States: In matrix converter 27 switching combination is taken place. 18 combinations where the output voltage and the input current vectors have fixed directions with magnitudes that vary with the input voltage phase angle and the output current phase angle respectively.3 combinations giving null output voltage and input current vectors. All three output phases are connected to the same input phase in these combinations. Space vectors of output take one of 6 fixed positions (varying amplitude), Space vectors of input current take one of 6 fixed positions (varying amplitude). All space vectors are at the origin (zero length). 6 combinations in which each output phase is connected to a different input phase. Both magnitude and phase of the resultant vectors are variable in these cases. By this way total 27 switching combination is taken place in Matrix converter. Topologies of Bi-directional Switch: Bi-directional switches capable of blocking voltage and conducting current in both directions are required by the Matrix Converter. Common Emitter Bi-directional Switch is used in this thesis which consists of two diodes and two IGBTs those are connected in anti-parallel. The diodes are included to provide the reverse blocking capability.](image-2.png "1 .") 1![Figure 1 : Space vector modulation process](image-3.png "Figure 1 :") 23![Figure 2 : space vector trajectory Space vector pulse width modulation is applied to output voltage and input current control In figure 2 six sectors are shown for six switches. The objective of space vector PWM technique is to approximate the reference voltage vector Vref using the six switching patterns. Two switches from the same phase should not be on at the same time, otherwise short circuit will occur in the same input side. One switch is always on at different phase with Vref. So a continuous flow of bus voltage is shown in circle(red marked).](image-4.png "Figure 2 :FFigure 3 :") 4![Figure 4 : Bidirectional switch](image-5.png "Figure 4 :") 57![Figure 5 : Input wave shape of Matrix converter Where, input voltage=100V(P-P) Time period T=0.0168sec (approx) And frequency f=1/T=59.82Hz Figure 6 : Wave shape across the load Global Journal of Researches in Engineering ( ) Volume XVI Issue V Version I 42 Year 2016](image-6.png "Figure 5 :FFigure 7 :") 8![Figure 8 : induction motor speed](image-7.png "Figure 8 :F") 105![Figure10: THD analysis using FFT When pulse signal is converted into ac signal some harmonic distortion is created that should not be cancelled. The lower the percentage, the higher the speed performance. It is related to frequency.](image-8.png "Figure 10 : 5 N") ![Journal of Researches in Engineering ( ) Volume XVI Issue V Version I Global Journal of Researches in Engineering ( ) Volume XVI Issue V Version I 45 Year 2016 F](image-9.png "Global") © 2016 Global Journals Inc. (US) © 2016 Global Journals Inc. (US)AC Voltage Analysis Using Matrix Converter ## This page is intentionally left blank * Direct Space Vector PWM Strategies for Three-Phase to Three-Phase Matrix Converter YugoTadano ShotaUrushibata MasakatsuNomura YukihikoSato MuneakiIshida Research & Development Center, MEIDENSHA CORPORATION July 19, 2010 * Research on Matrix Converter Based on Space Vector Modulation ZhanjunQiao WeiXu China. Research Journal of Applied Sciences, Engineering and Technology 101601 16 2013 Department of Mechanical and Electronic Engineering, North China Institute of Science and Technology * Optimization of Indirect Space Vector Modulation Strategy for Matrix Converter DKuzmanovic JLettl Faculty of Electrical Engineering March 27, 2012 Czech Technical University in * A tech-nology review PWWheeler JRodriguez JCClare LEmpringham Converter IEEE Transactions on Industrial Electronics 49 2 2002 * Matrix converter modulation strategies: A new general approach based on space-vector representation of the switch state DCasadei GSera ATani LZarri IEEE Transactions on Industrial Electronics 49 2 2002