An Overview of a Hybrid Electric Vehicle (HEV) Transmission

This module consists of a lab, PowerPoint presentation, and modified syllabus which all relate to Toyota's continuously variable Hybrid Electric Vehicle (HEV) transmission. All materials were developed under a seed grant from the Center for Advanced Automotive Technology (CAAT).

The PowerPoint discusses the following: the use of a dry dampener in place of a torque converter, the various roles and controls of each motor in the transmission, structure and efficiency of motor magnets by angle orientation, speed sensor operation through magnets and coils, and power flow through the internal combustion engine, electric motors, batteries, transmission, and inverter under various driving conditions.

The lab is intended to familiarize technicians with common service point locations and procedures on a Prius Hybrid (2003-2011) such as coolant bleed and fill (engine and inverter), transmission fluid drain and fill, high voltage wiring, auxiliary battery and precautions, and activating Inspection Mode.

For educators looking to modify current courses, the syllabus has highlighted fields where the HEV transmission was incorporated into an automotive transmissions and transaxles course at Lewis and Clark Community College.