Tagged Questions
0
votes
1answer
148 views
3-phase power calculation when phase to phase voltages are different
I have a 3-phase power supply rated at 230VAC per phase. However, the phase to phase voltages are not equal. Suppose \$V_{RY}\$, \$V_{YB}\$ and \$V_{BR}\$ be the three phase-to-phase voltages between ...
3
votes
2answers
105 views
Why are the power transmission/distribution systems AC and not DC?
Is there a good reason why we are not in the process of completely converting our electrical transmission system to DC? The main reason for using AC on the grid (no offense Tesla, I love you man) was ...
4
votes
1answer
138 views
What causes sub-second mains voltage outages?
Many times I observed a following electrical event: mains voltage will suddenly drop and then immediately restore. This causes lights to blink and computers to restart.
I can't imaging what could ...
3
votes
5answers
573 views
What electrical anomaly can cause RCBOs to trip in apartments in several buildings at the same time?
Once I had a weird electrical event in an apartment building I live in. Suddenly the Residual Current Circuit Breaker with Overload protection (I'm sure it's exactly this kind of device) in the main ...
1
vote
2answers
1k views
What causes unequal phase-to-neutral voltages in three-phase distribution systems?
A four-wires cable runs into an apartment building to supply it with three-phase 380/220V alternating current. Each apartment is connected to one phase, different apartments are connected to different ...
2
votes
3answers
330 views
How do utility companies treat voltage deviations in distribution networks?
I live in a region where nominal mains voltage is 220 volts and state standards permit deviations within 5 percent continuously and within 10 percent for short periods. So if I measure the voltage in ...
7
votes
7answers
3k views
What causes overvoltage in power grid?
In the region where I live there's a state standard that says that mains voltage deviation can be within 5 percent continuously and within 10 percent for short periods of time, so if the mains voltage ...
4
votes
4answers
201 views
Why are power distribution systems so prone to massive faults?
Many region-wide blackouts (like this one or this one) are described as follows: some high-voltage equipment (like a generator or a transformer) fails and the grid gets overloaded and then protective ...
9
votes
5answers
523 views
Power grids : AC vs DC
We know that we have now 50/60Hz in our walls due to mainly historical reasons - back 100 years ago there were no ways to up/down scale DC voltage.
These days we just have problems due to that - ...
