Lec4 - 341 Energy Conversion - Updated

Lec4 - 341 Energy Conversion - Updated - Lec4 3F AC...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
341 - Electric Machinery Fundamentals MI - 1 Lec4 3 F AC Circuits Mahesh S. Illindala
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
341 - Electric Machinery Fundamentals MI - 2 Objectives Knowledge (repeating from memory): Define phase sequence Describe Y- D transformation of impedances for a balanced 3- f system Show a one-line diagram for a 3- f power system Comprehension (demonstrating understanding of terms and concepts): Summarize the relationships in Y- and D -connected 3- f systems Application (apply learned information to solve a problem): Calculate the apparent power, real power, reactive power and power factor for 3- f systems
Background image of page 2
Power in a Sinusoidal 1- F AC Circuit Figure 1-29(b): An ac voltage source supplying a load with impedance Z = Z q W v(t) = 2V cos( w t) i(t) = 2I cos( t– q ) (A) (V) ( W ) Unlike the dc circuit, power flow in sinusoidal ac circuits is more complex , because there can be a phase difference between the ac voltage and ac current supplied to the load. p(t) = v(t) i(t) = 2 VI cos( t) cos ( t– ) = VI cos (1 + cos ( 2 t )) + VI sin sin ( 2 t ) For the ac circuit in Figure 1-29(b), the instantaneous power drawn from the voltage source v(t) is given by Figure 1-30: Components of power supplied to a 1-phase load versus time Power supplied by the component of current in phase with the voltage Power supplied by the component of current 90 o out of phase with the voltage P = VI cos q Q = VI sin Average or Real power Reactive power ( watts ) ( VAR )
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/01/2012 for the course ECE 341 taught by Professor Keyhani during the Fall '08 term at Ohio State.

Page1 / 18

Lec4 - 341 Energy Conversion - Updated - Lec4 3F AC...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online