Problem 10.3 - Time-Domain Voltages from Frequency-Domain Solution
*
* The circuit for this problem is from textbook Chap. 10, Problem 20.
*
* NOTE: This is a two-part problem.
* 1. Solve for the steady-state ac voltages using a single-point
* .AC sweep at the given frequency of the source current.
* Print out the steady state voltages across each circuit element.
* Use the frequency-domain solution obtained with PSpice to express
* as a time-function the voltage across each of the passive devices
* and the input terminal voltage.
* 2. Use a SIN function source in place of the steady state ac current
* source. Change the .AC sweep to a .TRAN command with an analysis
* period equal to approximately five full periods of the SIN
* waveform. Use PROBE to graph V(1), V(1,2), V(2,3), and V(3).
* Compare the graphical responses with the time-function equations
* from Part 1.
*
* ===> CHALLENGE PROBLEM! The inductance has an impedance magnitude of 2000
* ohms at the given source frequency. At what frequency does the
* capacitance have an impedance magnitude of 2000 ohms? Re-run Part 2
* at this new frequency. Compare the results for the three voltages.
*
.OPT NOPAGE NOBIAS NUMDGT=5 ; Use this statement with Version 4.03 or
; later. For earlier versions delete NOBIAS.
IS1 0 1 AC ???? ??? ; Complete the ac source specification. Note
; that the current is given in milliamperes
; in the problem statement. It must be
; expressed in terms of amperes for PSpice.
R1 1 2 1K
L1 2 3 1M
C1 3 0 1U
RS 1 0 1e12 ; Resistance in parallel with the current
; source to provide a dc path to ground.
.AC LIN 1 ?????? ?????? ; Enter the frequency in hertz. Use
; six significant figures.
.PRINT AC IM(IS1) IP(IS1) VM(R1) VP(R1)
.PRINT AC VM(L1) VP(L1) VM(C1) VP(C1)
.END
Problem 10.3, Part 2. Time-Domain Voltages from Frequency-Domain Solution
*
* Use the SIN function and the .TRAN function with PROBE to display
* a graph of the circuit device time-dependent voltage waveforms.
* ===> You must use the results of Part 1 and calculate the t=0 voltage
* across the capacitance and the t=0 circuit current to use as initial
* conditions so that the transient part of the waveform will be
* eliminated. Otherwise the voltage waveforms will have very large
* t=0 transients (more than 1 kV) and the steady state response will
* appear to be zero on the PROBE graph.
*
.OPT NOPAGE NUMDGT=5 NOBIAS ; Use this statement with Version 4.03 or
; later. For earlier versions delete NOBIAS.
IS1 0 1 SIN(0 ???? ?????? 0 0 ???) ; Complete the statement.
R1 1 2 1K
L1 2 3 1M IC=??? ; Calculate initial conditions from
C1 3 0 1U IC=??? ; the time-domain solution, Part 1.
; You may delete the IC statement and
; ignore the effect of the start-up
; transient in the graphed waveform.
; If you do this, then you will have
; to change the y-axis scale to -8,8
; to clip off the t=0 transients.
RS 1 0 1e12 ; Resistance in parallel with current
; source provides a dc path to
; ground.
.TRAN 400N ??? 0 ??? UIC ; Complete the .TRAN statement.
.PROBE V(1) V(1,2) V(2,3) V(3)
.END
* Problem 10.3, Part 3. Time-Domain Voltages from Frequency-Domain Solution
*
* Use the SIN function and the .TRAN command with PROBE to display a
* graph of the circuit device time-dependent voltage waveforms.
* ===> You must use the results of Part 1 and calculate the t=0 voltage
* across the capacitance and the t=0 circuit current to use as initial
* conditions so that the transient part of the waveform will be
* eliminated. Otherwise the voltage waveforms will have very large
* t=0 transients (more than 1 kV) and the steady-state response will
* appear to be zero on the PROBE graph.
*