All Questions
61
questions
0
votes
2
answers
279
views
Why do we need admittance, susceptance and conductance?
What is the need for modelling circuits and transmission lines, and loads using variables stated above when we can use resistance in the real domain and reactance in the imaginary domain. Are not the ...
- 69
1
vote
1
answer
266
views
Watt meter and load
I have recently purchased a watt meter from Adafruit to measure the cumulative watthours of a non-constant (DC) current.
When I use a multimeter to test the voltage and amperage, I get what I expect: ...
- 25
5
votes
2
answers
1k
views
Why do power supplies get less efficient at high load?
Many PSUs follow the 80 PLUS standards, and it shows efficiency peaks at intermediate loads.
Power supplies are less efficient at low loads due to quiescent current. But why are they also less ...
- 749
2
votes
1
answer
169
views
What is the loading factor of a generator?
Looking at an ENTSOE paper, I have seen this table in which the typical ''loading factors'' of different generation types are listed (see figure below). But, what is this????
I was supposing that it ...
0
votes
3
answers
118
views
Self regulating effect of loads for frequency control
How does power absorption from loads depend on frequency? I know that during a frequency deviation in power grid, there are primary reserves which control the frequency, but I know there is also the ...
1
vote
1
answer
62
views
Rated nominal power of generation with respect to load condition
In the electric power grid generation and consumption must be always the same. For sure the load change continuously in time, therefore an equal generation change must always correspond to the load ...
0
votes
5
answers
503
views
What determines the current flow in a load?
If we apply a load of 100KVA to a 100 volts source, we will get 1000 amperes of current through it.
If we apply the same load of 100KVA to a 1000 volts source we will get 100 amperes of current in the ...
- 1,498
1
vote
0
answers
44
views
nature of the load connected to the electric power grid
I know that loads can be modeled either as constant impedance or as fixed power P and Q. I also know that the majority of the loads are constant impedance type but I don't know exactly the percentage. ...
0
votes
1
answer
116
views
Can loads absorb more power than needed/requested?
I was designing the governor of a generator, implementing in Digsilent Powerfactory a 1 bus grid like that in the picture.
The generator delivers 350 MW and the 3 loads withdraw respectively 25 MW, 25 ...
0
votes
0
answers
118
views
Internal EMF of a Synchronous Generator Relationship with Load side line Voltage
Say you have a 6-pole, star-connected, 60 Hz, 25 MVA rated, 600 V synchronous generator. After conducting open and short circuit tests you get the equivalent circuit with Xs = 600/(root(3)*14000) (...
- 39
0
votes
0
answers
304
views
How to calculate portable power station draining with other loads?
I want to buy a portable power station, it's basically a battery, the battery capacity at 14.8V/15Ah is 222Wh, I want to know how many times it will long for some loads, such as a simple light , or ...
- 1
3
votes
5
answers
3k
views
What load resistance will result in maximum power transfer - Art of Electronics
I am reading Art of Electronics book. There is a question:
Here is an interesting problem: What load resistance will result in maximum power being transfered to the load for a given source resistance?...
- 345
0
votes
0
answers
51
views
Reactive power doesn't add up in load flow analysis
I am doing a load flow analysis as part of my coursework in MATPOWER and need help figuring out the mathematics behind the bus data in the third table below. Basically, the three generators' real ...
0
votes
0
answers
36
views
I wnat to design a circuit with a DC load but need help calculating the required circuit breaker, cable etc on the AC side of the power supply
I need to design a circuit with a knowing DC load of 24Vdc 20 watts. Now I have a Puls PIC 120.241D power supply that I can use. My question is I need to spec the protective device on the incoming ac ...
- 1
3
votes
2
answers
638
views
System load vs. hourly system load (HSL)
Real-time electricity usage in Texas is graphed by ERCOT, the Electric Reliability Council of Texas. Today's graph can be found here, with a screen-grab below:
Note the difference between the lines ...
- 133