Load flow analysis ETAP

[Amineln]

Hello
Hello

I have a load= 200 KVA PF=100% so Amps = 288.7 but in load flow analysis load=191 KVA and Amps = 280.2 before circuit breaker , and load=188 KVA and Amps=280.2 after circuit

breaker the length of cable = 10 m why this difference ?
thank you

 

[xnuke]

Cable resistance and inductive reactance.

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
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[LionelHutz]

Also, a static load is defined using voltage and VA, so if the actual voltage is lower than what was used in the loading tab then you'll see a lower VA for that load. From your numbers, the voltage drop at the load is likely about 3% assuming you did use 0.4kV for the load voltage on the loading tab.

 

[Amineln]

thank for your answers but I think it's not enough

Initial value :

200 KVA v=400V PF=100% and I= 288.7 A

bus Operating voltage :=388V

operating load = 188 KVA (after circuit breaker)

VA=1.73 V I

I know we calculate operating voltage from voltage drop but we need also operating Amps and operating VA how we can calculate them and we have only operating voltage ?????

Does Etap calculate the current firstly then we deduce the operating load VA or the inverse ?

thank's

 

[LionelHutz]

In your case the static load is resistive which makes it easy to hand calculate the resistance if you wanted to. However, simple math tells you that on static loads (resistive, inductive, capacitive) the VA changes by the square of the voltage ratio. (388/400)^2 x 200

 

[wroggent]

You can change the model type to a different one if you don't like how this one behaves.