Design and implementation of the non-linear controller of step-down DC-DC converter

Number of pages: 97 File Format: word File Code: 32264
Year: 2014 University Degree: Master's degree Category: Electronic Engineering
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  • Summary of Design and implementation of the non-linear controller of step-down DC-DC converter

    Dissertation for receiving the master's degree "M.Sc."

    in the field of electrical engineering, power electronics

    Abstract:

    The materials that are examined in this thesis in order to simulate and implement the buck converter nonlinear controller are presented in four chapters. In general, the buck converter and the relationships governing it and the studies conducted on the buck converter and a control method to obtain the average output voltage to be equal to a desired level are presented. The control method presented includes a series of advantages and disadvantages. To improve the disadvantages and also to obtain a better result and obtain the output voltage with a constant level and reduce the ripple and settling time of the voltage at the output of the linear controller (PI) is introduced, which is combined with a non-linear control method (sliding mode control). All 3 controllers are simulated in the MATLAB environment in the fourth chapter, and the results can be seen. Also, at the end of the thesis, the controllers are compared separately against sudden load changes. style="direction: rtl;">Introduction

    DC sources are used in many industrial applications, so a device is needed that can convert a DC voltage source into a variable DC voltage source, this is done by a chopper. A chopper is a DC to DC converter that, like an AC transformer that can create the desired voltage by changing the number of turns, can directly convert the DC voltage to the desired DC voltage continuously.

    Choppers have many applications. It is usually used as a voltage regulator and converts the unregulated DC voltage into the desired regulated DC voltage and is used together with an inductor to create a DC current, especially for the current source inverter.

    Choppers are widely used to control the motor in electric cars, lifting forks, in mining. Among their features are accurate acceleration control, high efficiency and fast dynamic response. Another application of chopper is in reactive power compensation.

    Choppers are used in dynamic braking of DC motors to return energy to the source, which saves energy in transportation systems with many stops.

    One ??of the most important applications of chopper can be mentioned is the use in optimizing AC power networks.

    In sensitive loads, if If a fault occurs in the network, a backup power system (eg house battery) is required. This need for a continuous power supply system has led to the use of UPS power supplies. Choppers are used in these UPS to adjust the rectified voltage level. So that during the normal operation of the energy system, it is directed from the network to the backup power supply system, and in emergency situations, the backup system supplies the required load. In this type of UPS, a bi-directional chopper is used.

    Figure 1-1 bidirectional fly back [1]

    Choppers are divided into two groups, increasing and decreasing, based on the output voltage. In most DC-to-DC switching power supplies used in data and telecommunication equipment, a step-up converter is used whose task is to reduce line current harmonics and meet global specifications to control line current harmonic limits in DC sources. The boost converter is usually used in radars and ignition systems. Step-down converters are usually used in electric cars and DC filters.

    Nowadays modified choppers under the name of two-quadrant and four-quadrant have come to the market, and the first type of chopper is used in automatic control systems of renewable resources such as solar cells and wind turbines.

  • Contents & References of Design and implementation of the non-linear controller of step-down DC-DC converter

    List:

    Abstract

    Chapter One: Overview of studies done

    Introduction

    1-2- Researches done on DC-DC converters

    Chapter Two: Chopper introduction

    2-1- Introduction

    2-2- Control of dc-dc converters

    2-3- Converter Reducer

    2-3-1- Continuous current mode

    2-3-2- Boundary between continuous and discontinuous conduction

    2-3-3- Discontinuous conduction mode

    2-3-3-1- Discontinuous conduction mode with constant

    2-3-3-2- Discontinuous conduction mode with constant value

    2-3-4- Ripple Output Voltage

    Chapter Three: Sliding Mode Control

    31 Introduction

    3-2- Variable Structure Control

    3-3- Sliding Mode Control

    3-3-1- Reaching Stage

    3-3-2- Sliding Stage

    3-3-3- Advantages and Disadvantages of Sliding Mode Control

    3-4- Effect Evaluation Delay

    3-5- Noise investigation

    3-5-1- Boundary layer method

    3-5-2- Adaptive boundary layer method

    3-5-3- Viewer-based method

    3-5-4- High-order sliding mode control

    3-5-5- Intelligent methods

    3-6- Conclusion

    Chapter Four: Buck converter simulation

    4-1- Buck converter simulation in MATLAB software

    4-1-1- The role of LC circuit in filtering harmonics

    4-2- Buck circuit with feedback loop

    4-2-1 Buck converter simulation with PI controller:

    4-2-1-1- Proportional term of PID controller

    4-2-1-2- Integral term

    4-2-2- Buck converter simulation with SMC controller

    4-2-2- 1- Buck converter modeling:

    4-2-2- 2- Buck converter mode space model:

    4-2-2- 3- Sliding mode control of the buck converter:

    4-2-2- 4- Sliding control theory:

    4-2-2- 5- Description of the simulation file

    4-2-2- 6- Simulation results:

    4-2-2- 7- Notes:

    4-3- PISMC simulation results

    4-4- Comparison of inductor current and output voltage of buck converter with PI controllers and SMC and PISMC:

    4-5- Comparison of the buck converter output voltage with PI and SMC and PISMC controllers against sudden load changes:

    Appendix

    Source:

    [1] W. Perruquetti and J. Pierre-Barbot, Sliding mode control in engineering, Marcel Dekker, 2002.

    [2] J.-J. E. Slotine and W. Li, Applied nonlinear control, Prentice-hall, 1991. [3] S. Sastry and M. Bodson, Adaptive control, Prentice-hall, Englewood Cliffs, 1989. [4] I. D. Landau, R. Lozano and M. M' Saad, Adaptive control, Springer-Verlag, London. 1998. [5] J.-P. Su and C.-C. Wang, "Complementary sliding control of non-linear systems", Int. J. Contr., vol. 75, no. 5, pp. 360-368, 2002.

    [6] R. A. Decarlo, S. H. Zak and G. P. Matthews, "Variable structure control of nonlinear multivariable systems: a tutorial", IEEE Proc., vol. 76, no. 3, pp. 212-232, 1988. [7] C. Edwards, S. K. Spurgeon, Sliding Mode Control: Theory and Applications, Taylor & Francis, London, 1998. [8] O. Kaynak, K. Erbatur and R. Ertugrul, "The fusion of computationally intelligent methodologies and sliding-mode control- a survey'', vol. 48, no. 17, 2001.

    [9] Sliding mode in control, New York, 1992.

    [10] W. Gao and J. C. Hung, new approach'', IEEE Trans. 1993, no. 45-55. J. Elec. Eng., vol. 11, no. 1, pp. 45-59, 2003.

     

    [12] H. Lee, H. Shin, E. Kim, S. Kim and M. Park, ``Variable structure control of manipulator using linear time-varying sliding surfaces'', IEEE Proc. Intelligent Cnf., pp. 806-811, 1998.

     

    [13] R. G. Roy and N. Olgac, ``Robust nonlinear control via moving sliding surfaces n-th order case'', IEEE Proc. Contra. Cnf., pp. 943-948, 1997. [14] H.. Morioka, K. Wada, A. Sabanovic and K. Jezernik, “Neural network based chattering free sliding mode control”, IEEE Contr. Cnf., pp. 1303-1308, 1995. [15] Y. Li, S. Qiang, X. Zuhang and O. Kaynak, “Robust and adaptive backstepping control for nonlinear systems using RBF neural networks”, IEEE Trans. on Neural Net., vol. 15, no. 3, pp. 693-701, 2004.

     

    [16] M. O. Efe, C. Unsal, O. Kaynak and X. Yu, “Sliding mode control of a class of uncertain systems”, IEEE Contr. Cnf., pp. 78-82, 2003.

     

    [17] H. S. Ramirez and E. C. Morles, ``A sliding mode strategy for adaptive learning in adalines'', IEEE Trans. Circuits Syst. I, vol. 42, pp. 1001-1012, 1995.

     

    [18] G. G. Parma, B. R. Menezes and A. P. Braga, ``Sliding mode backpropagation: control theory applied to neural network learning'', IEEE Contr. Cnf., pp. 1774-1778, 1999.

     

    [19] K. D. Young, V. I. Utkin and U. Ozguner, ``A control engineer's guide to sliding mode control'', IEEE Trans. Contra. Sys., vol. 7, no. 3, pp. 328-342, 1999.

     

    [20] L. Dugard and E. I. Verriest, "Stability and control of time delay systems", Lecture Notes in Control and Information Sciences, no. 228, Springer-Verlag, 1997.

     

    [21] L. M. Fridman, E. Fridman and E. I. Shustin, ``Steady modes and sliding modes in the relay control systems with time delay'', IEEE Proc. Contra. Cnf., pp. 4601-4606, 1996.

     

    [22] F. Gouaisbaut, W. Perruquetti and J. P. Richard, ``A sliding mode control for linear systems with input and state delays'', IEEE Proc. Contra. Cnf., pp. 4234-4239, 1999.

     

    [23] I. Boiko and L. Fridman, ``Analysis of chattering in continuous sliding-mode controllers'', IEEE Trans. Automatic. Contr., vol. 50, no. 9, pp. 1442-1446, 2005. [24] M.-S. Chen, Y.-R. Hwang and M. Tomizuka, "A state-dependent boundary layer design for sliding mode control", IEEE Trans. Automatic. Contr., vol. 47, no. 10, pp. 1677-1681, 2002. [25] P. Kachroo and M. Tomizuka, "Chattering reduction and error convergence in the sliding-mode control of a class of nonlinear systems", EEE Trans. Automatic. Contr., vol. 41, no. 7, pp. 1063-1068, 1996. [26] A. Cavallo and C. Natale, “Output feedback control based on a high-order sliding manifold approach”, IEEE Trans. Automatic. Contr., vol. 48, no. 3, pp. 469-472, 2003.

    [27] S. Laghrouche, F. Plestan and A. Glumineau, ``Higher order sliding mode control based on integral sliding mode'', Automatica, Article in press, 2007.

    [28] S. Oh and H. Khalil, ``Nonlinear output feedback tracking using high-gain observer and variable structure. control'', Automatica, vol. 33, pp. 1845-1856, 1997.

     

    [29] G. Bartolini, and P. Pydynowski, ``An improved, chattering free, V.S.C. scheme for uncertain dynamical systems'', IEEE Trans. on Automat. Cont., vol. 41, no. 8, pp. 1220-1226, 1996. [30] M.-S. Chen, C.-H. Chen and F.-Y. Yang, "An LTR-observer-based dynamic sliding mode control for chattering reduction", Automatica, vol. 453, pp. 1111-1116, 2007. [31] J.-S. R. Jang, C.-T. Sun and E. Mizutani, Neuro-fuzzy and soft computing, Prentice-hall, 1997.

    [32] V. Mkrttchian and A. Lazaryan, "Application of neural network in sliding mode control", IEEE Contr. Cnf., pp. 653-657, 2000.

     

    [33] Y. Li, K. C. Ng, D. J. Murray-Smith, G. J. Gray and K. C. Sharman, ``Genetic algorithm automated approach to the design of sliding mode control systems,'' Int. J. Contr., vol. 63, pp. 721-739, 1996. [34] Q. Ding, H. Chen, C. Jiang and Z. Chen "Combined indirect and direct method for adaptive fuzzy output feedback control of nonlinear system", Journal of Systems Engineering and Electronics, vol.

Design and implementation of the non-linear controller of step-down DC-DC converter