RLC Current Delay (2, 11)

The phase delay (angle) is positive for current lagging voltage.

Equations:

TAN(φs) =

XL----------------------– XC

 

 

R

XC =

------------1

XL = ω ⋅ L

 

ω ⋅ C

 

1 1

-------- – -------

XC XL TAN(φp) = ----------------------

1

---

R

ω = 2 ⋅ π ⋅ f

Example:

Given: f= 1107_Hz, C=80_lf, L=20_ mH, R=5_‡.

Solution: ω=672.3008_r/s, φs= -45.8292_°, φp= -5.8772_°, XC=18.5929_‡, XL=13.4460_‡.

DC Capacitor Current (2, 12)

These equations approximate the dc current required to charge the voltage on a capacitor in a certain time interval.

Equations:

I = C ⋅

V

V = – Vf – Vi

t = tf ⋅ ti

-------

 

 

t

 

 

Example:

Given: C=15_lf, Vi=2.3_V, Vf=3.2_ V, I=10_A, ti=0_s.

Solution: ΔV=0.9000_V, Δt=1.3500_ls, tf=1.3500_ls.

Capacitor Charge (2, 13)

Equation:

q = C ⋅ V

Example:

Given: C=20_lF, V=100_V.

Solution: q=0.0020_C.

5-14 Equation Reference