Title Page
Contents
ABSTRACT 10
Ⅰ. Introduction 12
1.1. Background and trend of research 12
1.2. Purpose and content of the study 18
1.3. Composition of this paper 20
Ⅱ. Basic circuit structure and ripple analysis 22
2.1. Introductory 22
2.2. Topology of a multi-phase interleaved parallel DC-DC converter 22
2.3. Buck mode phase current ripple analysis 26
2.3.1. D≤1/3 27
2.4. Interleaved multiphase converter with coupled inductor 29
2.4.1. Two phase interleaved buck converter with coupled inductor 30
2.4.2. Multiphase interleaved parallel bidirectional DC-DC converter based on coupled inductors 32
Ⅲ. Current sharing controller 34
3.1. Current sharing control block diagram 34
3.2. Simulation of Current Sharing Controller 36
Ⅳ. InterCell Transformers 40
4.1. Introduction of InterCell Transformers 40
4.1.1. Separate Transformers 42
4.1.2. Monolithic Transformers 45
4.2. Intercell Transformer design 48
Ⅴ. Simulation Analysis 51
5.1. Modeling Analysis 51
5.2. Simulation results 57
Ⅵ. Conclusion 61
6.1. summary 61
6.2. Future Work 63
References 64
Appendix 70
Abstract (in Korean) 72
〈Table 1-1〉 The parameters of the multiphase DC-DC converter 51
〈Figure 1-1〉 The topology of the multiphase interleaved shunt bidirectional DC-DC converter 13
〈Figure 1-2〉 a parallel-coupled multi-winding structure with symmetrical geometry. 15
〈Figure 1-3〉 Butterfly Interleaving Multiphase Coupled inductor 16
〈Figure 1-4〉 Model of the 8 phase monolithic ICT. 17
〈Figure 2-1〉 multi-phase interleaved parallel bi-directional DC-DC converter 23
〈Figure 2-2〉 Ratio between output current ripple and maximum phase current ripple 24
〈Figure 2-3〉 six-phase interleaved parallel bi-directional DC-DC converter 26
〈Figure 2-4〉 Buck mode main waveforms for D ≤ 1/3 28
〈Figure 2-5〉 Two-phase interleaved buck converter with coupled Inductor 30
〈Figure 2-6〉 Topology of Multiphase interleaved parallel bidirectional DC-DC converter based on coupled inductors 32
〈Figure 3-1〉 Control of six phase Buck Converter 35
〈Figure 3-2〉 Simulation of six-phase buck converter with open loop control for D ≤ ⅓ 36
〈Figure 3-3〉 Simulation of six-phase buck converter with current sharing control for D ≤ ⅓ 37
〈Figure 3-4〉 Simulation of six-phase buck converter with open loop control for ⅓ 〈D ≤ ⅔ 37
〈Figure 3-5〉 Simulation of six-phase buck converter with current sharing control for ⅓ 〈D ≤ ⅔ 38
〈Figure 3-6〉 Simulation of six-phase buck converter with open loop control for D〉 ⅔ 38
〈Figure 3-7〉 Simulation of six-phase buck converter with current sharing control for D〉 ⅔ 39
〈Figure 4-1〉 ICT and its magnetic circuit. 40
〈Figure 4-2〉 Topology consisting of a two-winding transformer 44
〈Figure 4-3〉 Topology types of the Monolithic ICT Ladder topologies. 45
〈Figure 4-4〉 Circular topologies. 46
〈Figure 4-5〉 Double ladder type topology. 47
〈Figure 4-6〉 Core Structure 48
〈Figure 5-1〉 Modeling of ICT 52
〈Figure 5-2〉 Distribution of magnetic flux density in ICT core. 53
〈Figure 5-3〉 Coupling Simulation Diagram. 54
〈Figure 5-4〉 Current Sharing Controller 56
〈Figure 5-5〉 Phase current waveform without current sharing control at D ≤ ⅓ 57
〈Figure 5-6〉 Phase current waveform with current sharing control at D ≤ ⅓ 58
〈Figure 5-7〉 Phase current waveform without current sharing control at ⅓ 〈D ≤ ⅔ 58
〈Figure 5-8〉 Phase current waveform with current sharing control at ⅓ 〈D ≤ ⅔ 59
〈Figure 5-9〉 Phase current waveform without current sharing control at D〉 ⅔ 59
〈Figure 5-10〉 Phase current waveform with current sharing control at D〉 ⅔ 60