[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

# Re: [femm] Bearing currents and faraday cage

- To: femm@yahoogroups.com
- Subject: Re: [femm] Bearing currents and faraday cage
- From: hans.krieg@transport.alstom.com
- Date: Mon, 9 Dec 2002 12:17:25 +0100
- Sensitivity:

    Dear Chronis

    I think it is hardly possible to use FEMM in modelling this phenomenon
    since the origin of it is electrical and not magnetical. Important
    influence factors are the capacitances between stator windings,stator frame
    and rotor body. FEMM is purely focused on the interaction between currents
    and magnetic fields and not the electrical fields and voltages.

    Interesting papers on the subject of bearing current due to inverter drives
    can be found on the website of Allen Bradley (Rockwell Automation):

    www.ab.com/drives/techpapers/ieee/ieee.html

    Kind reagrds,

    Hans

    "Polychronis Vallianatos" <rotechen@otenet.gr> on 07-12-2002 20:06:31

    Please respond to femm@yahoogroups.com

    To: <femm@yahoogroups.com>
    cc: (bcc: Hans KRIEG/NLRID01/Transport/ALSTOM)

    Subject: [femm] Bearing currents and faraday cage

    Dear Dave, dear All,
    there is a usual problem,in Variable Speed Drive (VSD), with fast
    switching valves (eg IGBTs), the premature bearing failure, due to
    Electrically induced flutting.
    The common mode induced currents, break the lubricant film, discharging
    the common mode voltage to the grounded end shield.
    One of the remedies is the Faraday Cage, in the motor Air Gap.
    this could have the form of a copper foil, or conductive paint.

    How could this be modeled by FEMM ? How could FEMM take in account the
    high frequencies that the phenomenon take place (or fast voltage rise
    times? eg 30V / microsec)?

    Has anyone done like that in FEMM, or do you propose any Paper on the
    Topic?
    Do anyone have any FEMM modeled Variably Frequency Driven Motor?

    Thanks in Advance,

    Chronis
    pvallian@yahoo.com
    rotechen@otenet.gr

    Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.

    CONFIDENTIALITY : This e-mail and any attachments are
    confidential and may be privileged. If you are not a named
    recipient, please notify the sender immediately and do not disclose
    the contents to another person, use it for any purpose or store or
    copy the information in any medium.

- Prev by Date: Rif: Re: [femm] Bug in move function
- Next by Date: Re: [femm] Bug in move function
- Previous by thread: Re: [femm] Bug in move function
- Next by thread: 'block' and 'group' confussion
- Index(es):
  - Date
  - Thread