The Queen Mary 2 was totally without power for at least an hour when a capacitor bank exploded, blowing the reinforced steel door off of a power cabinet (like those used in "enclosed" power substations). The capacitors are used to filter harmonics from the electronic drive for the electric propulsion motors whose power can total over 100 MW. The ship was in open water and so was in no immediate danger. It finally got under way again a few hours later at reduced power.
The cause of the problem was not EMC as such, but was definitely related to the electrical system. A number of capacitors in the capacitor bank were later found to be bulging from overheating. The equipment to monitor the condition of the capacitors (by monitoring electrical parameters) did not catch the developing problem before the explosion. The electrical system was unable to reconfigure itself to maintain even partial power. So yes, I could believe that a ship could get into trouble quickly if there were a major electrical failure. If this turns out to be the cause for the Concordia disaster, I am surprised that international standards had not been revised and enforced in light of the power failure on the Queen Mary 2. Donald Borowski EMC Engineer Schweitzer Engineering Labs Pullman, WA, USA From: John Woodgate <[email protected]> To: [email protected] Date: 01/17/2012 11:05 AM Subject: Re: cruise liner harmonic interference? Sent by: [email protected] In message <ca7a2231c689d14c9df8bc211ade9f03082...@dcexchmb100vm.tennant.tco.corp>, dated Tue, 17 Jan 2012, "Bender, Curtis" <[email protected]> writes: >An interesting (but sad) article for the EMC and PSTC interests. > >http://www.guardian.co.uk/world/2012/jan/14/italian-cruise-disaster-caus >e-power > This must be pure speculation. Furthermore: According to this scenario, a power surge or "harmonic interference" could have caused a malfunction in the generators feeding the ship's six diesel-electric engines, while back-up systems failed to provide power with sufficient speed. This would have caused the ship to lose navigational power and steering control and to veer off course. ..is typical ignorant journalistic mumbo-jumbo. Losing power would cause 'reset to default' of all systems, which doesn't sound like 'veer off course' to me. In any case, these critical systems are subject to redundancy requirements. A total power failure must have infinitesimal probability. >I?m sure it?s possible but how probable is it to lose ALL power long >enough to run a ground? Seems to me that should have been one of the >first items covered in a Risk Assessment. >Are EMC test standards typically followed for cruise liners IEC TC80 deals with ship electrics and electronics, but the IMO has a great influence and is often accuse of excessive conservatism. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
