Title: Objective
1Objective
- Provide an analysis of the existing Waltz-Mill
system. - Determine the affect on the system of adding an
additional motor load. - Determine the necessary changes to safely add the
new load and increase the power factor on T6 and
T7.
2Existing System AnalysisWith SKM Power Tools
Software
- A Load Flow analysis was performed with the
following data.
BKR5 306kVA .8
T10 568kVA .8
BKR15 450.75kVA .8
T11 220kVA .8
BKR10 225.81kVA .8
BKR13 375.89KVA .8
Location Load PF
T1 1300kVA .8
T2 1275kVA .8
BKR2 416.71kVa .8
BKR3 No load
3Existing System AnalysisWith SKM Power Tools
Software
- The following values will be found under the
current conditions - Percent loading for each feeder circuit
- Percent loading for each transformer
- Nominal voltage and percent voltage drop at each
switchgear - Optimal transformer taps
4 System Analysis with new load
- 500hp motor load added to secondary bus T7.
- Determine the size of the cable and breaker.
- Increase power factor on secondary bus of T6 and
T7 to .97 by adding a capacitor bank.
5Results and Recommendations
- Load flow analysis of existing system before tap
optimization. - Includes percent loading for all transformers and
feeders.
6Results and Recommendations
- Tap settings were optimized to minimize loss in
the system.
Load Flow results with optimized tap settings
7Results and Recommendations
- The full load ampacity for the motor was found
with the equation for FLA. - The breaker was sized at 125 FLA.
- The size of the capacitor bank needed to improve
the PF to .97 was found with the equation for QB.
Added motor and capacitor bank to T7
8Results and Recommendations
Added capacitor bank to correct T6 power factor
to 0.97
9Results and Recommendations
- The motor drew up to 683.92A
- 3-1/C, 500MCM, nonmagnetic cable was chosen
(ampacity of 810A) - A GE SK, Spectra motor circuit protector with
trip settings between 600-1200A was selected. - This trip current should be set to 800A.
Load flow analysis of system with motor and
capacitor banks added