Compact storage-based resistance spot welding power supplies / von M.-Tech. Krishna Dora Venkata Mohana Murali. Erster Gutachter: Prof. Dr.-Ing. Joachim Böcker, Zweiter Gutachter: Prof. Dr.-Ing. Jürgen Petzoldt. Paderborn, 2016
Content
- Abstract
- Zusammenfassung
- Acknowledgements
- Contents
- List of Figures
- List of Tables
- List of Acronyms
- List of Symbols
- 1 Introduction and Thesis Overview
- 1.1 Background
- 1.2 Storage-based welding power supply - state of the art
- 1.3 Research objectives
- 1.4 Dissertation Outline
- 2 Specifications of the desired power supply
- 2.1 Introduction
- 2.2 Output characteristics
- 2.3 Other desirable characteristics
- 2.3.1 Audible noise
- 2.3.2 Galvanic isolation between storage element and output
- 2.3.3 Load duty ratio
- 2.3.4 Weight and volume
- 2.4 Specification sheet
- 3 Power Supply Topology
- 3.1 Modularity
- 3.2 Potentially suitable converter topologies
- 3.3 Interleaved buck converter
- 3.4 Interleaved buck controlled resonant converter
- 3.5 Interleaved phase-shifted full-bridge converter
- 3.6 Inter-cell transformer based buck converter
- 3.7 Interleaved tapped-inductor buck converter
- 3.8 Quantitative comparison of the qualified topologies
- 4 Energy Storage
- 4.1 Introduction
- 4.1.1 Criteria for selection of a storage technology
- 4.1.2 Storage technology pre-selection
- 4.1.3 Main factors influencing the storage system sizing
- 4.2 Evaluation of electrolytic capacitor based storage
- 4.2.1 Energy density
- 4.2.2 Equivalent circuit representation
- 4.2.3 Characteristics of equivalent series resistance
- 4.2.4 Power loss calculation
- 4.2.5 Designing for life time
- 4.2.6 Step-wise process for storage sizing
- 4.3 Evaluation of double layer capacitors based storage
- 4.3.1 Power density
- 4.3.2 Frequency characteristics
- 4.3.3 Equivalent circuit model
- 4.3.4 Step-wise process for storage sizing
- 4.4 Evaluation of flywheel storage system
- 4.4.1 Geometrical structure used for the analysis
- 4.4.2 Step-wise process for storage sizing
- 4.4.3 Step 1: Determining the motor dimensions and loss distribution
- 4.4.4 Step 2: Determining charging and discharging losses
- 4.4.5 Step 3: Determining the optimal FSS volume
- 4.4.6 Step 4: Obtaining the volume versus efficiency curves
- 5 Implementation Using Double Layer Capacitors and Interleaved Buck Converter
- 5.1 System overview
- 5.2 Obtaining the worst case plant transfer function
- 5.2.1 Effect of operating duty-cycle
- 5.2.2 Effect of load resistance
- 5.2.3 Effect of load inductance
- 5.2.4 Worst case plant transfer function
- 5.3 Influence of source resistance
- 5.4 Controller design
- 5.5 Experimental Setup
- 5.6 Results
- 6 Conclusions and Future Work
- A Appendix A
- B Appendix B
- B.1 Flywheel basics
- B.2 Motor type selection
- B.3 Depth of discharge
- B.4 Steel flywheel can be the best choice for SBRSWPS
- B.5 Motor temperature under intermittent loading
- Bibliography