ROBICON Perfect Harmony - Medium voltage converters

Perfect Harmony medium voltage drives

Thread Starter: Scadamooch   Started: 11/4/2011 1:59 PM   Replies: 5

  11/4/2011, 1:59 PM

Scadamooch Joined 11/2/2011 Last visit: 11/14/2011 Posts: 4 Rating:  (0)	(0)  Greetings, I'd like to have a discussion with other users of the above mentioned drives.  I'm trying to learn from other users that use these units as to their reliability and maintenence issues. I would appreciate hearing from anyone with real-world field experience on these drives. Thanks, Scadamooch
	Top

  5/1/2012, 7:18 AM

Gennadiy Joined 3/3/2006 Last visit: 3/15/2013 Posts: 5 Rating:  (0)	(0)  We have about 50 Perfect Harmony in my country, produced in Germany, USA, China. I can say that the drives are very reliable, and additional options - cells' bypass and reserve fan make it "non-stop" device. Also it continue to be working with very deep voltage drop, while other equipment is already stopped/faulted. === Edited by Gennadiy @ 5/1/2012 7:19 AM [GMT ] ===
	Top

  5/2/2012, 11:11 AM

timmyLDeng Joined 8/25/2011 Last visit: 2/15/2013 Posts: 20 Rating:  (2)

(0)  Generally they are very reliable. They are used a lot in oil & gas offshore as if there is a problem with the cells they can bypass and keep running. You need to keep them clean and check the electrical connections as you would with most HV equipment.  The only problem with them is if the main transformer fails. It has special windings and can be quite hard to fix quickly. Of all of the ones I know of I have only know 4 transformers to fail in the last 8 years.  There are some early PH leagacy drive which are 15 years old still going strong with no problems.

Top

  5/4/2012, 9:53 PM

Bob_Harvey Joined 6/6/2011 Last visit: 12/4/2012 Posts: 2 Rating:  (0)

(0)  I have to agree with the other posters. Normally you lock the doors half way through commissioning, and never open them again. There are PM schedules published, but I know machines that havn't been touched in 5 years and are still working fine. Spares availability is good: some of the control PCBs have been updated so replacing one may mean replacing another next to it, but everything is available one way or another, even for the Legacy drives that were mentioned (Some of those have been updated to NGX2 controls, and there will soon be a standard way of doing that too).

Top

  9/12/2012, 8:57 AM

K Vijay Joined 4/30/2011 Last visit: 11/24/2012 Posts: 13 Rating:  (1)

(1)  Perfect Harmony is a proven drive with excellent features like 55 % UV tripping, optional cell bypass without stopping the machine in case of cell failure,  allowing wide distances between motor and drive without any special output chokes, elegant power factor control and even no autotuning is required. I woked with atleast 50 drives of GEN III and GEN IV drives Another intereseting feature is that eventhough incoming voltage is MV like 4.16 KV or 13.8 KV, all power components are of LV level  690 V K. Vijay

Top

  3/29/2013, 2:49 PM

N. Vijay Joined 3/17/2013 Last visit: 5/20/2013 Posts: 10 Rating:  (0)	(0)  Cell modular design also facilitates easy replacement. But lately noticed that there are issues  with System Interface Boards of particular firmware and CPU firmware for nuisance trippings at times Vijay
	Top