Predictive Control of Three Phase AC/DC Converters

Contents
Contents
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1 Introduction 1
2 Voltage Source Converter 7
2.1 Space Vector Based Description of VSC . . . . . . . . . . . . . . . 8
2.2 Mathematical Model of VSC . . . . . . . . . . . . . . . . . . . . . 8
2.2.1 VSC Model in Natural Coordinates . . . . . . . . . . . . . . 11
2.2.2 VSC Model in Stationary Coordinates . . . . . . . . . . . . 13
2.2.3 VSC Model in Rotating Coordinates . . . . . . . . . . . . . 14
2.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3 Control Strategies for VSC 17
3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.2 Voltage Oriented Control . . . . . . . . . . . . . . . . . . . . . . . 17
3.3 Switching Table based Direct Power Control . . . . . . . . . . . . . 21
3.4 Direct Power Control with Space Vector Modulator . . . . . . . . . 25
3.5 Virtual Flux Based Control . . . . . . . . . . . . . . . . . . . . . . 28
3.6 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.6.1 Steady State Operation . . . . . . . . . . . . . . . . . . . . 32
3.6.2 Transient Operation . . . . . . . . . . . . . . . . . . . . . . 36
3.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4 Predictive Direct Power Control 41
4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.2 Principles of Model Based Predictive Control . . . . . . . . . . . . 41
4.3 Variable Switching Frequency Predictive Direct Power Control . . 42
4.4 Current Harmonics Spectrum Control . . . . . . . . . . . . . . . . 46
4.5 Predictive Direct Power Control with Reduced Switching Frequency 49
4.6 Constant Switching Frequency Predictive Direct Power Control . . 50
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