[bwilson4web]

Originally Posted by dcb

For starters, I'm just trying to understand the source of the measurements and how much processing/inferring has already occured by the time you log them.

Would you mind going through these questions in order? . . .

1. Is there an actual torque sensor on mg1? Or is it "inferred" by the ECU and current sensors or???

The maintenance manual does not identify a torque sensor on the shaft nor a sensor in the stator mounts. We just know the hybrid vehicle (HV) ECU reports both torque and rpm in the same MG1 response packet.

2. Is there an actual torque sensor on mg2? Or is it "inferred" by the ECU and current sensors or???

The maintenance manual does not identify a torque sensor on the shaft nor a sensor in the stator mounts. We just know the hybrid vehicle (HV) ECU reports both torque and rpm in the same MG2 response packet.

3. Is there an actual rpm sensor on mg1? Or is it "inferred" by the ECU and voltage sensors or???

The maintenance manual and papers show a position encoder that uses an elliptical metal disk with two, 90 degree coils. In fact, the coils are in a ring. Here is an example, not from a Prius, but similar architecture.

4. Is there an actual rpm sensor on mg2? Or is it "inferred" by the ECU and voltage sensors or???

We know that the motor generator encoder signals go directly to the HV ECU which in turn drives the power electronics in the inverter. These are power, brushless motor generators and the HV ECU handles all of the position sensing and drives the inverter gates that let them work as either motors or generators.

We also know there are Hall Effect current sensors for two of the three legs to the larger, MG2. We suspect these are used to detect unbalanced stator loads that might occur when there is a stator failure.

5. And I assume traction battery voltage and amps comes from actual voltage and current sensors on the battery. But if you could confirm that to please.

Correct. There is a Hall Effect current sensor connected to the dedicated battery controller. Both the battery controller and HV ECU can report traction battery current. However, the battery controller only reports 19, module-pair, voltages, no summary. The HV ECU reports the total voltage. Since the HV ECU pretty well runs the show and needs to modulate the inverter power pulses, it may pull the traction battery voltage from the inverter.

The best way to view the two MGs are as massive, stepper motors under control of the HV ECU that has a separate, bi-directional, 'dumb' inverter. The HV ECU is what makes the Prius drivetrain work with specialized functions distributed to other ECUs such as brakes, air-bag, electric power steering, battery, body, and the immobilizer.

Bob Wilson