Back forward sweep algortihm for radial distribution systems (modified)

Backward/ forward sweep algorithm for three-phase load-flow analysis of radial distribution systems.

Description

Backward/ forward sweep algorithm for three-phase load-flow analysis of radial distribution systems. In the backward sweep, Kirchhoff's Current Law and Kirchhoff's Voltage Law are used to calculate the upstream bus voltage of each line or a transformer branch. In the forward sweep, the voltage at each downstream bus is then updated by the real and imaginary components of the calculated bus voltage multiplying with the corresponding ratio.

Acknowledgements

Back Forward Sweep Algortihm For Radial Distribution Systems inspired this file.

• MATLAB release: MATLAB 7.12 (R2011a)

[david]

hey I really don't understand the problem with your matrix however i'v uploaded a new version of this program which is faster and shorter.
BTW this program is designed for dis. systems so be aware of the fact that high active and reactive input would destabilize the program and a real system.
if your not working with dis. systems i suggest you use the guess or newton program (simple,fast respectively).

[Bramer]

i get NaN when using the following matrices. Any idea why??
bdata=[ 1 0 0
2 0.053333333 0.02375
3 0 0
4 0.038333333 0.02375
5 0.038333333 0.02375
6 0 0
7 0 0
8 0.038333333 0.02375
9 0.053333333 0.02375
10 0 0
11 0.038333333 0.02375
12 0.022833333 0.014
13 0.012 0.0075
14 0.012 0.0075
15 0.012 0.0075
16 0.00225 0.00125
17 0.038333333 0.02375
18 0.038333333 0.02375
19 0.038333333 0.02375
20 0.038333333 0.02375
21 0.038333333 0.02375
22 0.038333333 0.02375
23 0.038333333 0.02375
24 0.038333333 0.02375
25 0.038333333 0.02375
26 0.038333333 0.02375
27 0.022833333 0.014166667
28 0.0125 0.008
29 0.0125 0.008
30 0.0125 0.008
31 0.0095 0.00575
32 0.0095 0.00575
33 0.0095 0.00575
34 0.0095 0.00575];
ldata=[ 1 2 0.00580 0.00238
2 3 0.00532 0.00218
3 4 0.00815 0.00226
4 5 0.00741 0.00206
5 6 0.00741 0.00206
6 7 0.01559 0.00268
7 8 0.01039 0.00179
8 9 0.01559 0.00268
9 10 0.01039 0.00179
10 11 0.00650 0.00112
11 12 0.00520 0.00089
3 13 0.00780 0.00134
13 14 0.01039 0.00179
14 15 0.00520 0.00089
15 16 0.00260 0.00045
6 17 0.00890 0.00247
17 18 0.00815 0.00226
18 19 0.01031 0.00235
19 20 0.00937 0.00213
20 21 0.00937 0.00213
21 22 0.01299 0.00223
22 23 0.01299 0.00223
23 24 0.01559 0.00268
24 25 0.01039 0.00179
25 26 0.00650 0.00112
26 27 0.00520 0.00089
7 28 0.00780 0.00134
28 29 0.00780 0.00134
29 30 0.00780 0.00134
10 31 0.00780 0.00134
31 32 0.01039 0.00179
32 33 0.00780 0.00134
33 34 0.00520 0.00089];