Delta/Wye 3-Phase Using Mesh Analysis

Click For Summary
SUMMARY

This discussion focuses on solving a 3-phase circuit using mesh analysis, specifically a balanced Delta source with Phase A at 480V (0 degrees), Phase B at -120 degrees, and Phase C at 120 degrees, connected to a balanced Wye load with an impedance of 0.99 + j 0.66. The mesh equations provided are Vab = I1 * (Z1 + Z2) - I2 * Z2 and Vbc = -I2 * Z2 + I2 * (Z2 + Z3). The user reported a line current of 234.3A at -33.7 degrees from a previous method, while their calculation for I1 yielded 233.3A at -131 degrees, raising concerns about the accuracy of their mesh equations.

PREREQUISITES
  • Understanding of 3-phase circuit theory
  • Proficiency in mesh analysis techniques
  • Familiarity with complex impedance calculations
  • Knowledge of phasor representation of voltages and currents
NEXT STEPS
  • Review mesh analysis for 3-phase circuits
  • Study complex impedance in balanced Delta and Wye configurations
  • Learn how to derive mesh equations for 3-phase systems
  • Practice solving 3-phase circuit problems using simulation software like LTspice
USEFUL FOR

Electrical engineering students, circuit designers, and professionals working with 3-phase systems who need to enhance their understanding of mesh analysis and circuit calculations.

jmast1161
Messages
1
Reaction score
0
Hi, I have to solve a 3-phase circuit using mesh analysis. The source is a balanced Delta Phase A = 480V at 0 deg, Phase B is at -120 deg, and Phase C is at 120 deg. The load is a balanced Wye load at 0.99 + j 0.66. My mesh equations are as follows:

Vab = I1 * ( Z1 + Z2) - I2 * Z2
Vbc = -I2 * Z2 + I2 * (Z2 + Z3)

My professor said not to worry about the loop inside of the Delta Source since they will all cancel.

We did this problem in class a different way and got a line current of 234.3A at -33.7 degrees.

When I solved for I1 I got 233.3A at -131 degrees. I am not sure if it is just coincidence that my magnitude is close to the same value or if I messed the angle somehow. Whenever I plug I1 into solve I2, I get a value that is way off. I really want to know if my equations are correct for the Mesh Analysis.
 
Engineering news on Phys.org
You need to show your work before we can answer.
 
Most likely this can only be answered by an "old timer". I am making measurements on an uA709 op amp (metal can). I would like to calculate the frequency rolloff curves (I can measure them). I assume the compensation is via the miller effect. To do the calculations I would need to know the gain of the transistors and the effective resistance seen at the compensation terminals, not including the values I put there. Anyone know those values?

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
Replies
14
Views
5K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 11 ·
Replies
11
Views
5K
  • · Replies 4 ·
Replies
4
Views
7K
Replies
9
Views
2K
  • · Replies 17 ·
Replies
17
Views
3K
  • · Replies 15 ·
Replies
15
Views
4K