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Electric Motors

Discussion in 'Gen 2 Prius Main Forum' started by Russ Yost, Jun 15, 2005.

  1. Russ Yost

    Russ Yost New Member

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    Some nights I lie awake trying to guess at information about all the electric motors in my '05 Prius. It would be great if some knowledgable owner could list the motors and for each, list the type (eg, dc, synchronous) voltage (12 volts, 250 volts, 550 volts), and power source (ICE, HV battery, converter, 12 volt battery, etc). Include the AC compressor, various coolant pumps, fans, etc. Include generators.

    If this is too much to ask, please point me to a source of information.

    Thanks in advance! :?
     
    #1 Russ Yost, Jun 15, 2005
  2. CHART

    CHART Member

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    From: http://home.earthlink.net/~graham1/MyToyot...PriusFrames.htm (one of the best Prius sites I have ever seen!!)

     
    #2 CHART, Jun 15, 2005
  3. Russ Yost

    Russ Yost New Member

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    Thanks, Rick. That is an excellent site. It clarified for me how MG1 starts the ICE. But I'm curious about other motors than MG1 and MG2, for example the compressor for the AC is driven by its own electric motor. What type, what voltage, whence the electric power input, etc? Ditto for the coolant pump motors and other motors (not accessory motoros such as windwhield wiper motors, which I assume are DC motors powered at 12 volts from the auxiliary 12 volt battery).
     
    #3 Russ Yost, Jun 15, 2005
  4. DanMan32

    DanMan32 Senior Member

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    You may want look for and get the New Car Features for 2004 Prius. You can download it in PDF pieces from TechInfo.Toyota.com for a subscription fee. You might be able to locate it elsewhere. You can also do searches in this site, we have discussed stuff like that extensively.

    MG1 and MG2 are 500V syncronous 3 phase AC motors. The battery is 206V, and the AC compressor is 206V sychronous 3 phase AC.
    The inverter has a booster circuit, which is essentially a switching power supply to convert the battery 206V to/from 500V for/from the motors.
    Each phase of each of the 3 motors has 2 field effect transistors in a push/pull configuration, controlled by the HV ECU.

    All the other motors are standard 12V motors, though some, such as the cabin blower and battery blower fan motor have their speeds controlled by pulse width modulation.

    The inverter contains a DC/DC converter which subs for a traditional alternator. It turns 206V down to 13.8-14V using a switching power supply.
     
    #4 DanMan32, Jun 21, 2005
  5. Russ Yost

    Russ Yost New Member

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    Thanks, Dan. You answered my question completely. In the last sentence, did you really mean a range of 3.8 to 14 volts for the output of the DC-DC converter?
     
    #5 Russ Yost, Jun 21, 2005
  6. DanMan32

    DanMan32 Senior Member

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    Oops, no I meant 13.8-14V, just fixed the post.

    The DC-DC converter has 2 modes: 13.8 (no charge) or 14V (charge Aux battery). OK, 3 modes: Off.

    The thing that gets me is that Toyota says not to charge the battery with more than 3 amp charge current, yet there is nothing determining the charge current from DC/DC converter. It is all voltage based, and the DC/DC converter can put out at least 80A (it is fused at 100A, the battery at 150A).
     
    #6 DanMan32, Jun 21, 2005
  7. Russ Yost

    Russ Yost New Member

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    I wondered about that, too, but figure a charger might be left "on" for hours and the aux battery temperature could build up and damage it. The DC/DC converter is under the control (I assume) of the ECU, which is smart enough to avoid the temperature build-up problem. A high current (high rate of heat input) is OK for a short time because of the significant "heat capacity" of the aux battery.
     
    #7 Russ Yost, Jun 21, 2005
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