Hey all,
I work for a small rural electric cooperative (4400 meters) with basically no technology. I'm a recent EE grad and am trying to apply what I've learned, and sometimes it's paid off. However, I've learned experience is almost more important than an education.
We're having voltage issues on a 3-phase feeder, particularly where a V-phase tap extends 6.5 miles off and feeds 5 irrigation services. This area of our system is pretty low density (system average is 2 meters/mile). The operations manager has had 2 different sets of capacitor banks installed: One set of (3) 50 kVAR on the mile of 3-phase preceding the V-phase tap, and a set of (2) 100 kVAR 2 miles beyond the 3-phase/V-phase junction.
This V-phase tap also serves some houses. During the winter, the capacitors are taken off line because the cause an over voltage to the houses near the irrigation, as well as a horrible power factor(leading). During the summer months, the capacitors must be online to compensate for the large inductive irrigation loads, otherwise voltage won't be sufficient to start the wells. Another large issue we face with this is rain during the summer: Irrigations don't run and the typical residential cooling load is virtually gone, causing over voltage. Until the heat is back and the fields have dried.
We've gone through 3 different scenarios that might help.
1. Rebuild the V-phase line, upgrading the wire size and adding the 3rd phase to help with the large irrigation loads. Won't we still need the capacitors to offset the large inductive loads, despite the anticipated help balancing voltage with the 3rd phase? This is a sizable rebuild and will cost $200,000+.
2. Install voltage regulators on the V-phase line. I think I'm leaning toward this solution; much lower cost as well.
3. Automate the capacitors. The cost involved with this is too great. Especially considering the load on this substation. As I type this the total substation load is only 350 kW and it peaks at 500 kW.
Am I missing something super obvious? A portion of the V-phase line will be rebuilt for a nearby city's water well service, but that's not happening for a while.
Thanks for the advice.
I work for a small rural electric cooperative (4400 meters) with basically no technology. I'm a recent EE grad and am trying to apply what I've learned, and sometimes it's paid off. However, I've learned experience is almost more important than an education.
We're having voltage issues on a 3-phase feeder, particularly where a V-phase tap extends 6.5 miles off and feeds 5 irrigation services. This area of our system is pretty low density (system average is 2 meters/mile). The operations manager has had 2 different sets of capacitor banks installed: One set of (3) 50 kVAR on the mile of 3-phase preceding the V-phase tap, and a set of (2) 100 kVAR 2 miles beyond the 3-phase/V-phase junction.
This V-phase tap also serves some houses. During the winter, the capacitors are taken off line because the cause an over voltage to the houses near the irrigation, as well as a horrible power factor(leading). During the summer months, the capacitors must be online to compensate for the large inductive irrigation loads, otherwise voltage won't be sufficient to start the wells. Another large issue we face with this is rain during the summer: Irrigations don't run and the typical residential cooling load is virtually gone, causing over voltage. Until the heat is back and the fields have dried.
We've gone through 3 different scenarios that might help.
1. Rebuild the V-phase line, upgrading the wire size and adding the 3rd phase to help with the large irrigation loads. Won't we still need the capacitors to offset the large inductive loads, despite the anticipated help balancing voltage with the 3rd phase? This is a sizable rebuild and will cost $200,000+.
2. Install voltage regulators on the V-phase line. I think I'm leaning toward this solution; much lower cost as well.
3. Automate the capacitors. The cost involved with this is too great. Especially considering the load on this substation. As I type this the total substation load is only 350 kW and it peaks at 500 kW.
Am I missing something super obvious? A portion of the V-phase line will be rebuilt for a nearby city's water well service, but that's not happening for a while.
Thanks for the advice.
