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When inverter shuts down due to overtemperature will it forward power from MG1 to MG2?

Discussion in 'Gen 2 Prius Technical Discussion' started by alexmol, Apr 28, 2011.

  1. alexmol

    alexmol Junior Member

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    If the Inverter shuts itself down due to overtemperature it will stop providing power to the 12V bus and A/C.
    I guess it will also stop forwarding current to/from the battery.

    My question is: Will the inverter still forward power from MG1 to MG2 when the ICE turns?

    Regards!
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    When the inverter shuts down, you should expect that no power is being forwarded anywhere. This is why the car quickly comes to a stop.
     
  3. alexmol

    alexmol Junior Member

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    So the reports about driving for some miles using the ICE with loss of power aren't inverter shutdown related?
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    They are probably more related to a weak traction battery. If the inverter truly shuts down then MG1 and MG2 will not be functional and there will be no 12V bus power after the 12V battery fades.
     
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  5. seilerts

    seilerts Battery Curmudgeon

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    There are two possibilities:

    A problem in the hybrid system causes the system main relays to open, isolating the HV battery. The car becomes extremely sluggish and won't go into reverse.

    A problem with the inverter cooling system causes the inverter to scale back on its duty cycle, shutting down the DC-DC converter and disallowing A/C, but still letting some current flow between the HV battery and the MGs. I don't think anyone has ever recorded peak regen/assist with the car in a P0A93 condition, but if you suppose that the current limit is cut to 25 amps from 100, then Ohmic heating is 1/16 of normal. The car will be somewhat sluggish, since full assist is not available.
     
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