Chapter 1 Power Electronic Systems

1. Chapter 1 Power Electronic Systems • Introduction • Power Electronics versus Linear Electronics • Applications Chapter 1 Introduction

2. Power Electronic Systems • Block diagram • Role of Power Electronics • Reasons for growth Chapter 1 Introduction

3. Linear Power Supply • Series transistor as an adjustable resistor • Low Efficiency • Heavy and bulky Chapter 1 Introduction

4. Introduction: Switching Power Electronics Linear regulator Goal: control VX such that Vo=Vo,REF Plus: simple accurate, high-bandwidth Minus: low efficiency  Chapter 1 Introduction

5. Switching power converters Vo(t) VIN <Vo> Add filtering Vo(t) VIN <Vo> Add real devices • Note: • only lossless elements • L, C energy storage Chapter 1 Introduction

6. Switch-Mode Power Supply • Transistor as a switch • High Efficiency • High-Frequency Transformer Chapter 1 Introduction

7. Basic Principle of Switch-Mode Synthesis • Constant switching frequency • pulse width controls the average • L-C filters the ripple Chapter 1 Introduction

8. Application in Adjustable Speed Drives • Conventional drive wastes energy across the throttling valve to adjust flow rate • Using power electronics, motor-pump speed is adjusted efficiently to deliver the required flow rate Chapter 1 Introduction

9. Power Processor as a Combination of Converters • Most practical topologies require an energy storage element, which also decouples the input and the output side converters Chapter 1 Introduction

10. Uninterruptable power supply - UPS 220 V 220 V ~ Batt 24V load • Converter 1 rectifies line-frequency ac into dc • Capacitor acts as a filter; stores energy; decouples • Converter 2 synthesizes line-frequency ac to load Chapter 1 Introduction

11. Power Flow through Converters • Converter is a general term • An ac/dc converter is shown here • Rectifier Mode of operation when power from ac to dc • Inverter Mode of operation when power from ac to dc Chapter 1 Introduction

12. Scope and Applications Chapter 1 Introduction

13. Interdisciplinary Nature of Power Electronics Chapter 1 Introduction