I think you don't need an isolation transformer just only to get rid of harmonics. You can just use an inductor or inductor capacitor combination for the same purpose.
Also, VFDs are modified sine wave, i.e square wave. Not recommended for transformer charging. A PSD(Phase switching device) would do the work but I think it will be expensive
1. Just curious, why would transformer's no load current consume 10% of battery power? No load current of any transformer should be below 1-2% of rated current. Introducing more circuitry will result in wasting more energy.
2. I would use magnetic contactors and timers so that after I energize...
Actual impedance will be unchanged, but percentage(per unit) impedance will change as the base MVA has been changed.
By the way, In any power system modelling you need to specify the base MVA and base voltage of any unit(generator, transformer, motor etc) so it doesn't really matter which base...
Hi everyone. I'm new member of this forum.
I've been using etap for a couple of months and recently I'm trying to model a 230/132/33kV YNa0d1 autotransformer in my project. The problem is, etap lets me choose between 2 winding and 3 winding transformer but no autotransformer can be inserted...
Those three pad mounted transformers showed in SLD will draw around 0.9A in total(Considering 0.3% no load current) during no load condition. So, T5 CT secondary will give 0.9*5/630=6.9mA as output. Each meter and protective relays has a minimum resolution. That's why you are not seeing any...
HV cable screens should be grounded at one end, not both ends. If it's grounded at both ends then there will be an induced current flowing through the screen which will heat up the screen- resulting in deteriorating the insulation of cable.
Normally AC resistance is 60% higher than DC...
You now have a system of 5000kVA with percentage impedance of 5%. Paralleling with new transformer will double the capacity and fault current as well. If I was the designer, I would keep the sources same and divide the loads into two separate buses with an automated bus coupler which will close...
