Date
Time
2
2
2
2
2
Sum
Total customers:
9:53
11:05
13:20
20:32
23:05
Customers Duration (mins)
570
65
189
59
525
80
68
120
5
30
1357
354
50000
1) Determine distribution reliability indices (SAIFI, SAIDI, CAIFI, CAIDI, MAIFI, ASAI)?
2) What is/are the most important one(s)? Why?
3) Do you suggest any other additional indices?
For MAIFI calculation: Assume that there are 4 momentary substation breaker operations in the system, each operated once on that day as follows:
Breaker No. custormer affected
1
860
2
1450
3
1200
4
675
1) Determine distribution reliability indices (SAIFI, SAIDI, CAIFI, CAIDI, MAIFI, ASAI)?
Constants:
Ni:
NT:
No:
Calculated Indices:
1357 customers interrupted
50000 total customers served
5 total number of interruptions
SAIFI:
SAIDI:
CAIFI:
CAIDI:
MAIFI:
ASAI:
0.0271
0.425
0.00368
15.7
0.0702
99.97
probability of experiencing a power outage
minutes
the average number of interruptions for a customer who was interrupted
minutes
momentary interruptions on the 2nd
% system availability
2) What is/are the most important one(s)? Why?
I believe that the most important indices are those that have to do with the duration of the interruption whether its on the customer or
system side such as SAIDI and CAIDI. The customer indices are the ones that should be prioritized as the customer does not wish to have their
power interrupted at all or at least not for too long. Knowing the average duration that the customer experineces an intrerruption is
important because this can assist the process of asset management. I believe that you can get very specific with these indices (SAIFI,
SAIDI,CAIDI), as specific as, the feeder and the sections of the feeder that are experiencing frequent interruptions. Honing in on specific areas
to optimize the grid will improve the SAIFI but it will also improve the SAIDI and most importantly the CAIDI. This will call for device
maintenance or maintence on those parts of the feeder.
3) Do you suggest any other additional indices?
I suggest the speculation of the Load and Energy Based Indices such as:
• ENS
• AENS
• ACCI