Skip to main content
16-Pearl
January 1, 2025
Question

Mathcad Community Challenge January 2025: AC Circuits

  • January 1, 2025
  • 12 replies
  • 10772 views

Happy New Year! This month's challenge is based around electrical engineering, specifically an AC circuit.

 

Calculation Challenge

An AC electrical circuit consists of the following components connected in series:
• A 120 Volt 60 Hertz power source
• A 50 Ohm resistor
• A 0.20 Henry inductor
• A 10 micro Farad capacitor

 

Calculate the following for this circuit:
• The reactances of the inductor and capacitor
• The impedance in the circuit
• The current in the circuit
• The power dissipated in the circuit
• The phase angle of the circuit

 

Graphing Challenge

Using an XY Plot or a Chart Component, graph the following in the same plot or chart over a minimum of 2 cycles:
• The current in the circuit.
• The voltage in the circuit.
• The voltage drop across the resistor.
• The voltage drop across the inductor.
• The voltage drop across the capacitor.

 

You can use the values from the calculation challenge, or you can use generic values. The point is to communicate that the current, total voltage, and voltage drop across the resistor are in phase; that the voltage drop across the inductor leads the current by a quarter cycle; and that the voltage drop across the capacitor lags the current by a quarter cycle. You may want to use 2 y-axes, one for current and one for voltage.

 

Mathcad Prime 10 Challenge

Using the advanced input controls like sliders, buttons, check boxes, etc., allow people to change one or more values in the Calculation Challenge to see how that affects the calculated values.

 

Find the Mathcad Community Challenge Guidelines here!

 

Disclaimer: I am not an electrical engineer. I apologize in advance if any of my terminology offends your sensibilities.

 

 

 

12 replies

ttokoro
21-Topaz I
21-Topaz I
January 2, 2025
23-Emerald IV
January 3, 2025
19-Tanzanite
January 9, 2025

I'm no electrical engineer, but here's how I tackled the challenge:

Jan2025.png

19-Tanzanite
January 16, 2025

Just noticed that my calculation of the cumulative average, used in the calculation of dissipated power, should have a divisor of k+1, not just k.  This is because Mathcad's origin is 0 not 1.  However, the correction makes no significant difference!

Alan

ttokoro
21-Topaz I
21-Topaz I
January 18, 2025

1. Add phase shift of sine wave.

2. Add transient responces of 3 waveforms, with all 120VRMS.

3. Add rectifier radio bottuns.

 

image.pngimage.png

t.t.
ttokoro
21-Topaz I
21-Topaz I
January 19, 2025

Transient responce of sine wave with phi and rectifier can not calculate by Laplace Transform method. So, need more Mathcad  skill to solve it.image.png

t.t.
23-Emerald IV
January 19, 2025

Can be done in express...:

LucMeekes_0-1737322751213.png

Luc

ttokoro
21-Topaz I
21-Topaz I
January 22, 2025

Ver. 3 can chage each of R, L, C to short it.  Applied voltage  has angle Z. Therefore, RL circuit can start no transient responce.

You can see RC, RLC or LC circuit's transient responces.

image.pngimage.png

t.t.
ttokoro
21-Topaz I
21-Topaz I
January 23, 2025

Version 4. Solved by using the odesolve of Prime 10.0.1.

image.png

t.t.
18-Opal
January 24, 2025

Thank you for your iterations, Tokoro-san!

And for everyone else, the challenge submission period ends in one week (end of January 31), so if you were thinking about giving it a try but haven't yet, now's the time!

18-Opal
January 31, 2025

Today's the last day for submitting for the write-up!

 

(I'm also very curious on how Dave Martin will discuss Ttokoro's 8 versions...)

ttokoro
21-Topaz I
21-Topaz I
January 25, 2025

Version 5. Solved by using the convolution integral of Prime 10.0.1. 

ttokoro_0-1737778188268.png

image.png

t.t.
ttokoro
21-Topaz I
21-Topaz I
January 26, 2025

Version 6. Solved by using the convolution * of Prime 10.0.1.  Sampling 1000 data for one cycle's period,T. 

 

image.png

image.png

t.t.
ttokoro
21-Topaz I
21-Topaz I
January 27, 2025

Version 7. Solved by using the Fourier series to make 120 V AC wavefroms  of Prime 10.0.1. 

 

image.png

t.t.