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BRANCH : ELECTRICAL ENGINEERING�SEMESTER : 3RD �SUBJECT : CIRCUIT & NETWORK THEORY�

CHAPTER : 06

TOPIC : POLYPHASE CIRCUIT

FACULTY : DR. MRUTYUNJAY DAS

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Mayurbhanj School Of Engineering, Baripada

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CONTENTS

  • Polyphase System
  • Phase sequence
  • Relation between Phase & Line quantities
  • Power equation
  • Measurement of 3 – phase power by 2 – wattmeter method

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POLYPHASE SYSTEM�

  • Polyphase System is a combination of two or more than two voltages having same magnitude and frequency but displaced from each other by an equal electrical angle.

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PHASE SEQUENCE�

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RELATION BETWEEN PHASE & LINE QUANTITIES�

  • Line voltage is the voltage measured between any two lines in a three-phase circuit. Phase voltage is the voltage measured across a single component in a three-phase source or load. Line current is the current through any one line between a three-phase source and load.
  • In a balanced Star system,

VR = VY = VB = Vph

IR = IY = IB = IL = Iph.

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RELATION BETWEEN PHASE & LINE QUANTITIES

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RELATION BETWEEN PHASE & LINE QUANTITIES

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MEASUREMENT OF 3 – PHASE POWER BY 2 – WATTMETER METHOD�

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MEASUREMENT OF 3 – PHASE POWER BY 2 – WATTMETER METHOD

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MEASUREMENT OF 3 – PHASE POWER BY 2 – WATTMETER METHOD

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