9: Polyphase Power
- Page ID
- 25299
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Learning Objectives
After completing this chapter, you should be able to:
- Define the differences between polyphase and single phase systems and detail their advantages.
- Determine line voltage, line current, phase voltage and phase current in three-phase systems.
- Analyze three-phase systems in both delta (\(\Delta\)) and Y (wye) configurations.
- 9.2: Polyphase Definition
- A polyphase system uses multiple current-carrying wires with multiple subgenerators, each with their own unique phase. This allows for considerable delivery of power to the load. The most popular scheme is the three-phase configuration.
- 9.3: Three-Phase Connections
- It is possible to configure systems using delta- or Y-connected sources with either delta- or Y-connected loads. One item to note is that delta-connected systems are always three wire systems while Y-connected systems can make use of a fourth neutral wire (the common point to which all three sources connect).