Huge VFD for testing motors from 690 V to 13.8 KV
Case: The VFD shall be capable to run maximum 27000 HP motor. Available power input is 34.5 KV.
Be sure when talking to your prospective variable frequency drives suppliers that both of you are on the same page. The VFD is usually rated for some max continuous current, with a corresponding short-time peak (measured at a few minutes and at a few seconds). There's a BIG difference in current for a 27000 HP machine at 13800V vs one at 690V!
You're going to have to be pretty clear on harmonic distortion allowances in both input and output waveforms if you're going to use the entire voltage range (690 to 13800 is a 1:20 range ... which also corresponds to frequency range, most likely). A lot of VFDs do not do well in terms of accurate control algorithms at very low (below 6 Hz) frequencies.
It's pretty much a given that you're going to be looking at the major VFD manufacturers for proven capabilities and product to get what you want: GE, Siemens, ABB, Gozuk, Toshiba, Rockwell, Not sure if Yaskawa and/or WEG has "proven" they can do that size of drive yet with any reliability.
If you're looking at a smaller player who is essentially repackaging components from one of the larger drives manufacturers, be sure they have the necessary support for your operation on an ongoing basis. A little bit of upfront legwork can save you a lot of headaches later.
Be sure when talking to your prospective variable frequency drives suppliers that both of you are on the same page. The VFD is usually rated for some max continuous current, with a corresponding short-time peak (measured at a few minutes and at a few seconds). There's a BIG difference in current for a 27000 HP machine at 13800V vs one at 690V!
You're going to have to be pretty clear on harmonic distortion allowances in both input and output waveforms if you're going to use the entire voltage range (690 to 13800 is a 1:20 range ... which also corresponds to frequency range, most likely). A lot of VFDs do not do well in terms of accurate control algorithms at very low (below 6 Hz) frequencies.
It's pretty much a given that you're going to be looking at the major VFD manufacturers for proven capabilities and product to get what you want: GE, Siemens, ABB, Gozuk, Toshiba, Rockwell, Not sure if Yaskawa and/or WEG has "proven" they can do that size of drive yet with any reliability.
If you're looking at a smaller player who is essentially repackaging components from one of the larger drives manufacturers, be sure they have the necessary support for your operation on an ongoing basis. A little bit of upfront legwork can save you a lot of headaches later.
