From WeberAuto.
See the amazing hybrid transaxle used in the 2019 – 2022 Toyota RAV4 Hybrid. Learn how this incredible transaxle functions in all nine modes of operation to help its sophisticated 2.5L engine deliver almost 40% brake thermal efficiency (BTE) for maximum fuel economy. This transaxle is also used in the 2018 and above Camry Hybrid, Avalon Hybrid, Lexus ES300h hybrid, and 2021 Venza Hybrid.
Corrections and Additions:
1. Addition: In EV mode, sling lubrication from gear movement is provided to drip channels that feed bearings, gears, and stator cooling. The RAV4 Prime uses an external electric oil pump for use in EV mode.
2. The 2021 Toyota Venza Hybrid also uses the P710 transaxle.
3. Correction: At 27 minutes: In overdrive with MG1 spinning backward, the ICE RPM should be less than when it is in direct drive. I incorrectly said the ICE RPM was higher.
4. Correction: The BTE chart at 23:06 is the wrong one for this ICE, it is for the non-hybrid ICE variant known as A25A-FKS (The related experiment is done by EPA, which provides all the details), while the engine for the Hybrid RAV4 is A25B-FKS with a slightly higher peak efficiency to 41%. The BTE plot of A25B is different from the A25A, with lower maximum torque, and a much larger high-efficiency area (it reaches 38% efficiency at 80 Nm until 2500 RPM), and the peak efficiency point/area is shifted to the left/downside. Thank you to viewer rt te for catching my error.
EPA Report: https://www.epa.gov/sites/production/files/2020-08/documents/sae-2019-01-0249.pdf
TIMELINE:
0:00 Start
0:09 Introduction
0:21 Model and vehicle usage
1:11 2.5L High-Efficiency Internal Combustion Engine (ICE)
1:35 The P710 transmission is used to keep ICE in its optimum RPM range
1:48 See the internal parts and functions of the P710 transaxle
2:00 Motor/Generator 2
2:40 Counter-driven gear and pinion gear
3:24 Final drive ring gear and differential
4:40 Overall gear ratio MG2 to Tires
6:00 MG2 Power, Torque, and RPM Ratings
7:02 MG2 motor and generator operation
8:00 MUST SEE Two Torque Paths to drive the vehicle
8:19 MG1 and the Power Split Device planetary gear set
8:50 Planetary gear set components
10:30 Ring gear connects to counter drive gear
11:25 Planet carrier connected to the ICE crankshaft
11:45 Sun gear connects to the MG1 rotor
12:01 Oil pump drive shaft
13:10 MG1 rotates the crankshaft to allow the ICE to start
13:40 Parking gear
14:23 MG1 has three functions
17:00 Underdrive, direct drive, and overdrive
18:00 The nine modes of operation of the electronic continuously variable transmission (eCVT)
18:46 Mode 1 "Ready" on with the vehicle stopped
19:28 Mode 2 Charging the high voltage (HV) battery with the vehicle stopped
20:39 Mode 3 Starting off and low-speed cruising on electric power only (EV Mode)
21:36 Mode 4 Starting off and low-speed cruising with a low SOC
22:25 Mode 5 Constant speed cruising (eCVT) operation
23:00 MUST SEE See the ICE RPM, power, and torque ranges for maximum ICE brake thermal efficiency (BTE)
25:17 Relationship between ICE and MG1 RPM to stay in the optimal ICE efficiency range while driving at 104 km/h (65 mph)
25:52 Underdrive example
26:35 Direct drive example at 1650 ICE RPM
27:00 Overdrive example MG1 stops rotating
28:08 MG1 rotates backward for additional overdrive or power generation
29:19 MG1 Power, Torque, and RPM Ratings
29:45 Mode 6 Constant speed cruising (eCVT) operation with low SOC
30:39 Mode 7 Full Throttle Acceleration
31:27 Mode 8 Deceleration and regenerative braking
32:22 Mode 9 Reverse
32:38 MUST SEE Rotor differences between P610, P710, and P810 transaxles
33:24 MUST SEE RAV4 Prime P810 MG2 rotor difference (51% more power and ~36.5mm thicker)
34:33 Motor Stators, stator cooling, and stator temperature
36:00 Transmission oil pump (ICE driven)
36:45 Motor resolvers (position, speed, and direction sensors)
37:17 Three-phase cable size differences between P710 and P610 transmissions/inverters
38:13 The RAV4 Q610 rear electric motor
ABOUT US:
Weber State University (WSU) Davis Campus – Automotive Technology Department – Advanced Vehicles Lab. A technical description and demonstration of the Toyota P710 hybrid transaxle. We teach current vehicle technologies to our automotive students at Weber State University and online. For more information visit: http://www.weber.edu/automotive
This video was created and edited by Professor John D. Kelly at WSU. For a full biography, see http://www.weber.edu/automotive/J_Kelly.html
Visit my other youtube channel https://www.youtube.com/user/vibratesoftware to see the amazing NVH app for vibration diagnosis!
ADDITIONAL TRAINING FOR YOU
Join us for hybrid and electric vehicle training with two online courses and in a 5-day on-campus boot camp with Professor John D. Kelly. See http://www.weber.edu/evtraining
DONATE TO OUR DEPARTMENT
Please consider a donation to the Department of Automotive Technology at Weber State University here: http://advancement.weber.edu/Automotive
