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Motor Control Modules

Location 

Both of the drive motors and the electric auxiliary fluid pump motor assembly are located within the transmission. They are each controlled by their own motor control module; each module is a flash-programmable micro-processor. Each motor control module is contained within the power inverter module. Also contained within the power inverter module is the hybrid/EV powertrain control module 1 micro-processor.

Operating Functions 

The motor control modules operate their respective motors based upon hybrid/EV powertrain control module 1 commands. Each motor control module controls the speed, direction and output torque of its respective drive motor or the electric auxiliary fluid pump motor assembly through the sequencing actuation of high current switching transistors called insulated gate bipolar transistors.

Communication and Hosted Diagnostics 

In addition to the internal serial peripheral interface bus communication circuit that the hybrid/EV powertrain control module 1 and each motor control module control use to communicate, the motor control modules also communicate on the hi-speed and hybrid serial data circuits. The motor control modules do not store their own Diagnostic Trouble Code (DTC) information. The hybrid/EV powertrain control module 1 will store motor control module associated DTC information for retrieval by a scan tool. The scan tool can communicate directly with each motor control module in order to retrieve data parameters only.

Circuit Inputs 

In addition to data parameters, each motor control module monitors its respective motor for voltage, current, speed, direction and temperature. Additionally, the motor control module monitors the insulated gate bipolar transistor components for temperature and proper operation. Some of the motor control module operation data is shared with the hybrid/EV powertrain control module 1.

Circuit Outputs 

Each motor control module controls its respective insulated gate bipolar transistor driver board that in-turn controls each motor. The motors operate using 3-phase AC electricity and are connected directly to the power inverter module via ring terminals and A/C connector rods. A single shielded cable connects the electric auxiliary fluid pump motor assembly to the power inverter module. This cable contains 3 individual wires that are connected to the 3 phases of the electric auxiliary fluid pump motor assembly. The cable is orange in color to alert the technician to the potential presence of high voltage.