Dear edison123,
thanks a lot for the information. The bearings are integrated inside the generator case (no pedestals). My feeling is that insulating both bearings is the method of choice: If you let one bearing be conductive you'll never know if a current loop could build with shaft external...
Hello,
we are about to specify a 6,25MW 6-pole induction generator for a DFIG drive system. I know that shaft voltages and resulting bearing failures have been a great deal sometimes. Also I know that effective shaft grounding at both drive ends helps, but how shall the bearing insulation be...
Hello all,
I have the following concern:
In an environment with power generation systems (app. 5-6MW generators) we want to operate at variable frequency and voltage (the island grid is build with an HVDC converter that allows this operation), where U/f ratio is a constant: E.g. 7kV<U<10kV and...
Hello MikiBg,
first thanks for the rapid answer.
Unfortunately there is not much more precise information than that I cutted out of the ABB brochure. What I also read is that the showed general AC filter is always used and tuned to the specific HVDC variant. However I am more curious how the...
Hi,
my company plans to use an ABB HVDC light converter system. In the technical description the keyword "harmonic cancellation PWM" is lined out. What I understood so far is that this feature was developed to reduce harmonic distortion of converters since avoiding harmonics is the best filter...
