1 / 6

Review of AC-circuit

Keys to deal with R, L, and C in an AC-circuit. Across R, voltage and current are in-phase Across L, the current lags behind voltage by 90 o Across C, the current leads voltage by 90 o. Review of AC-circuit. Also, . When two elements are in series  the same current passing through them

shadow
Download Presentation

Review of AC-circuit

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Keys to deal with R, L, and C in an AC-circuit • Across R, voltage and current are in-phase • Across L, the current lags behind voltage by 90o • Across C, the current leads voltage by 90o Review of AC-circuit Also, • When two elements are in series  the same current passing through them • When two elements are in parallel  the same voltage across them

  2. Basics I and V are in-phase R I lags V by 90 degree L I leads V by 90 degree C

  3. RLC in series Key: IR, IL, and IC are all in phase DVR ~ R DVL ~ XL DVC ~ XC DVmax ~ Z

  4. Imax IC How do you draw the phasor diagram? IR = IL DVR What if RLC are not in series? Which of the following is true (a) DVc = DVL, IC = IL (b) DVc = DVL, IR = IL (c) DVc = DVR, IR = IL (d) DVL = DVR, IR = IL (e) DVc = DVL+ DVR, IC = IL (f) DVc = DVL+ DVR, IR = IL DVL DVc = DVR+ DVL

  5. Power dissipation • Only R dissipates power P = I *DV, always For L and C, I and DV are 90o out of phase  PL = 0, PC = 0 For R, I and DV are in-phase  PR = IDV = Irms2R

  6. PR = IDV = Irms2R Where Irms = Vrms/Z i.e. Resonance in RLC circuit in series For a fixed AC voltage source, maximum power dissipation occurs when XL = XC, ie. When Z = R

More Related