Toyota's specifications don't explicitly state a power rating for the "generator" (i.e., MG1). They do give a power rating of 105 kW (~141 hp) for the "traction motor" (i.e., MG2). {For reference, the TCH ICE is rated at 110 kW (~147 hp) [Prius 57 kW (~76 hp)].}[COLOR=black] The Oak Ridge National Laboratory report number ORNL/TM-2007/190, Revised: "Evaluation of the 2007 Toyota Camry Hybrid Synergy Drive System" (downloadable from www.osti.gov/bridge) gives the following numbers for the TCH and for the 2004 Prius (see pages 3 and 48):

• MG1 — 40 kW (~54 hp) [Prius 33 kW (~44 hp)]
• MG2 — 105 kW (~141 hp), disputed by ORNL to be only 70 kW (~94 hp) under continuous operation [Prius 50 kW (~67 hp)]
• NiMH battery — 30 kW (~40 hp) [Prius 20 kW (~27 hp)]

MG1 cranks the ICE to start it, while MG2 applies a counter-torque to the output shaft to keep the motion of the car (whether stationary, accelerating, or moving at constant speed, forwards or backwards) largely unaffected during this operation. As alan_in_tempe has said, either motor-generator can act as a motor or as a generator, depending on the car's mode of operation and speed. The "overdrive" mode is what's often called "heretical mode" — when the ICE's rpm (and noise) drop drastically under steady-state cruising conditions.

Stan

 

The truth is the framus turns the gizmo once the thingamagig is rotating at a rate greater than the whatchamacallit.

I've attached this link before, and I apologize to those that have seen it previously, but here is an explanation of the power spliting device. It's fun to see how the PSD allows the ICE to come on while the car is stationary: MG2 doesn't move and the MG1 turns to start and continues to counter the ICE.

http://eahart.com/prius/psd/

This is actually for the Prius, but the principle for the TCH is similar.

Have fun.

 

Thanks for the correction, Stan. I can't remember where I got the mis-information that both motors were 55 HP.

-- Alan

 

Woah! I haven't been able to be online for awhile and got tons of answers! Thanks for the help guys, it seems like you all know a lot about this hybrid system.

 

I have just added a third bullet point plus information on the Prius' ICE to my post #11.

Stan