I have a long 13.8 kV cable with a large charging current. The cable terminates at a transfomer. Load current is 25% of the cable charging current. How do I set the 51 function on the cable protective relay?
I have 4-13.8 kV generators that have low resitance (150 amps)grounded neutrals. The generators are the same rating, have 2/3 pitch and are from the same manufacturer. Does anyone have a good reference (formulas) to calculate the circulating harmonic current between generators and resistors?
Has anybody had any experience with oscillatory transient overvoltages and harmonics issues due to capacitance on very long 13.8kV cables? Generally, capacitor switching on line causes problems. I have not heard of long lines without power factor corection capacitors that have these resonant...
The normal line to ground capacitive charging current for one phase is the line to neutral voltage divided by the capacitive reactance in ohms. Let's assume that each phase has a current of one amp when the system is unfaulted ( Ia +Ib +Ic = 1). When one of the phases is grounded, the total...
We have a 13.8 kV generator neutral grounded with a 100 amp resistor to limit transient overvoltages. The capacitive charging current is calculated to be 30 amperes @ 13.8 kV. The plant will expand with long 15 kV cables and the capacitive charging current may rise to 60 amperes. Is this...
Most large generators can provide increased output with additional cooling providing the prime mover has the ability to provide the additional power. The generator capability curve is expanded to show the new limits.
Question. Can the generator supply additional motor starting kva at the...
