Power Factor and Phasor Diagram

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SUMMARY

The discussion centers on the concepts of Power Factor and Phasor Diagrams in electrical engineering. The Power Factor is defined as the cosine of the phase angle, which is calculated using the formula: Phase angle = Tan Inverse((XL - Xc) / R), where XL represents Inductive Reactance, Xc represents Capacitive Reactance, and R is Resistance. The phasor diagram is described as having a horizontal line for Voltage and a downward line for Current, illustrating the phase angle when XL is greater than Xc. The acronym 'CIVIL' is suggested as a mnemonic to aid in understanding these concepts.

PREREQUISITES
  • Understanding of Power Factor calculations
  • Knowledge of Inductive and Capacitive Reactance
  • Familiarity with Resistance in electrical circuits
  • Basic skills in drawing Phasor Diagrams
NEXT STEPS
  • Study the relationship between Inductive Reactance (XL) and Capacitive Reactance (Xc)
  • Learn how to accurately draw Phasor Diagrams for various circuit configurations
  • Explore the implications of Power Factor on circuit performance
  • Investigate the use of the acronym 'CIVIL' in electrical engineering contexts
USEFUL FOR

Electrical engineering students, educators, and professionals seeking to deepen their understanding of Power Factor and Phasor Diagrams, particularly in the context of AC circuits.

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OK, Hello!

Have to make sure as I felt like I knew my stuff but failed my first exam, am I on the right tracks?

Power Factor = Cosine of phase angle

Phase angle = Tan Inverse ((XL-Xc)/R)

(So you know)
XL= Inductive Reactance
Xc= Capacitive Reactance
R = Resisstance

Am I right so far?

And for the phasor diagram, since in this case XL > Xc it would be illustrated as a horizontal line going towards the right, marked as Voltage, and a second line would go from the origin of the Voltage line downwards at an angle which would be the Phase angle, this second line illustrating the Current. Is that all I would have to do if I was told to draw a phasor diagram?

Is all this correct? My confidence has been wounded :(,,! I must make sure!, so please help if you can!
 
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Those equations are correct, even if they do look a little different from the standard ones.

Generally reactances sum to give a total reactance, so the outcome is either a capacitive system or an inductive system, rather than saying that there is more inductance than capacitance. Same result though.

If you aren't given numbers, then that phasor diagram would be accurate.

It may also help to keep the acronym 'CIVIL' in mind, as per the diagram attached.
 

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Thank you Zryn. Nice to know I'm on the right tracks. Will remember CIVIL, it will be very useful. And will also bare in mind about inductive and capacitive circuits. I'm sure if I knew the basics about Xc and XL circuits that what you said would be obvious so will have to work on that.
James
 

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