Hybrid System Output Control

WARNING: This page is about a different variant/trim than selected.

To control the drive force, HPCM detects the vehicle conditions based on information from the sensors and control modules, and controls the engine and traction motor.

HPCM judges the driving conditions based on the throttle position, vehicle speed, selector lever position, and other signals, and calculates the target drive force for those conditions. Based on the calculated target drive force and the status of each system, it distributes the required output between the engine and traction motor, and transmits the command signals to each control module. When each control module receives the signal, it performs control based on the command signal from the HPCM.

NOTE: The status of each system control can be checked from "Energy monitor" on either the "Navigation display" or combination meter "Information Display". Refer to "INFORMATION DISPLAY: SYSTEM DESCRIPTION " or "MULTI AV SYSTEM: SYSTEM DESCRIPTION ".

PRIMARY CONTROL MODULES FUNCTIONS DESCRIPTION

Control module	Description	Reference
ECM	Transmits engine status to HPCM via CAN communication. Performs engine start, stop, and other engine controls based on commands from HPCM. Outputs engine torque based on commands from HPCM.	Engine control system SYSTEM Engine stop control ENGINE STOP CONTROL: SYSTEM DESCRIPTION
Traction motor inverter	Transmits traction motor status to HPCM via CAN communication. Controls traction motor power generation or output based on commands from HPCM.	Motor power control TRACTION MOTOR INVERTER: PROTECTION CONTROL , Motor regeneration control MOTOR REGENERATION CONTROL
TCM	Transmits transmission status to HPCM via CAN communication. Activates clutch 1, clutch 2, and sub electric oil pump based on commands from HPCM. Performs shift change control according to the vehicle driving conditions.	A/T control system SYSTEM Sub electric oil pump system SUB ELECTRIC OIL PUMP SYSTEM: SYSTEM DIAGRAM Shift change control AT LOW FLUID TEMPERATURE
Li-ion battery controller	Transmits Li-ion battery status to HPCM via CAN communication.	Hybrid battery system SYSTEM
Electrically-driven intelligent brake unit	Transmits brake operating status to HPCM via CAN communication. Performs cooperative regenerative braking control together with HPCM.	Brake system SYSTEM Cooperative regenerative brake function COOPERATIVE REGENERATIVE BRAKE FUNCTION
Combination meter	Receives request signals transmitted by CAN communication from HPCM, and activates the indicator lamps on the combination meter and displays vehicle condition in the information display.	Meter system SYSTEM Information display TACHOMETER

< EXAMPLE OF ENGINE AND TRACTION MOTOR OUTPUT CONTROL ACCORDING TO DRIVING CONDITIONS >

HPCM controls the driving mode according to a range of driving conditions. Examples of vehicle driving modes under different driving conditions are shown below.

Hybrid System Activation

When the ignition switch is turned ON, HPCM turns ON the self shut-OFF relay and activates the hybrid system.

When Vehicle is READY

When the vehicle is READY, HPCM controls the system main relay and connects the high-voltage circuit. Refer to "SYSTEM MAIN RELAY CONTROL: SYSTEM DESCRIPTION ".
The combination meter activates the READY to drive indicator lamp, informing the driver that the vehicle is ready to drive.
HPCM detects the engine and Li-ion battery status based on signals from the ECM and Li-ion battery controller.
When engine is cold and Li-ion battery level is low, in order to warm the engine or charge the Li-ion battery, clutch 1 is engaged and the traction motor output is used to start the engine.

NOTE: Even after the engine is warm or the Li-ion battery level is sufficient, in some cases the engine still may not start due to other conditions.

Fig 1: Engine And Traction Motor Communication Diagram (Normal Driving)

Courtesy of NISSAN NORTH AMERICA, INC.

Normal Driving

When starting and driving at low speed (motor driving)
- When starting and driving at low speed, the mode is motor driving in which the electrical power from the Li-ion battery is used to drive the vehicle using traction motor output torque only.
  NOTE: Motor driving may not be engaged when engine is cold and Li-ion battery level is low, or due to other conditions.
- HPCM transits the engine stop command signal to the ECM, stopping the engine and disengaging clutch 1. It also transmits the drive command signal to the traction motor inverter, controlling the traction motor output.
- HPCM transmits the EV indicator lamp signal to the combination meter via CAN communication. When the combination meter receives the signal, it activates the EV indicator lamp.
  
  Fig 2: Engine And Traction Motor Communication Diagram (Low-Load Driving)
  Courtesy of NISSAN NORTH AMERICA, INC.
Low-load driving
- During low-load driving, the vehicle is driven by engine output torque, and the traction motor generates power to charge the Li-ion battery (when the Li-ion battery level is low).
- HPCM engages clutch 1 and starts the engine.
  
  Fig 3: Engine And Traction Motor Communication Diagram (Engine Starts)
  Courtesy of NISSAN NORTH AMERICA, INC.
- HPCM detects the Li-ion battery status from the Li-ion battery controller, and transmits the output torque signal to the ECM to control the engine output. The traction motor inverter controls the power generation by the traction motor and charges the Li-ion battery.
  
  Fig 4: Engine And Traction Motor Communication Diagram (Vehicle Stopped)
  Courtesy of NISSAN NORTH AMERICA, INC.

Vehicle Stopped

When the Li-ion battery level is low, engine output is used to generate power from the traction motor and charge the Li-ion battery.
NOTE: When the Li-ion battery level is sufficient, or due to other conditions, the engine may stop.
HPCM detects the Li-ion battery status from the Li-ion battery controller, and transmits the output torque signal to the ECM to control the engine output.
HPCM engages clutch 1 and disengages clutch 2.

Fig 5: Engine And Traction Motor Communication Diagram (Accelerating Or High Load)
Courtesy of NISSAN NORTH AMERICA, INC.

Accelerating or Load is High

When the accelerator pedal is fully depressed, the engine output torque assists the output torque from the traction motor.
HPCM engages clutch 1 and clutch 2 and transmits the output torque signal to the ECM and the drive command signal to the traction motor inverter, and controls the engine and traction motor output.

Fig 6: Engine And Traction Motor Communication Diagram (Deceleration Driving)
Courtesy of NISSAN NORTH AMERICA, INC.

Deceleration Driving

When decelerating, regenerative braking uses the motive power of the drive wheels to generate power from the traction motor and charge the Li-ion battery.

Cooperative control with the electrically-driven intelligent brake system increases the amount of power generated by regenerative braking. Refer to "BRAKE SYSTEM COOPERATION CONTROL: SYSTEM DESCRIPTION " for details.

Fig 7: Engine And Traction Motor Communication Diagram (Hybrid System Stop)

Courtesy of NISSAN NORTH AMERICA, INC.

Hybrid System Stop

HPCM detects the traction motor status (speed) via CAN communication from the traction motor inverter. When the ignition switch is turned OFF, then after the traction motor stops, the self shut-OFF relay turns OFF and the hybrid system stops.