Description And Operation: Description

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

The HCU (Hybrid Control Unit) controls whole hybrid systems and is connected with each control modules (ECM, TCM, MCU, BMS ECU etc.) by CAN interface. In addition this system uses the brake switch and Clutch Pressure Sensor (CPS) signals for controlling the hybrid system.

NOTE: CAN interface is divided into hybrid and chassis CAN lines.

Fig 1: Hybrid Control System Communication Diagram

Courtesy of KIA MOTORS AMERICA, INC.

The HCU controls power & torque distribution of the engine and motor, regenerative brake and fail - safe based on the vehicle information, driver's demand, engine information and high voltage battery information.

Fig 2: Hybrid Control System Communication Diagram

Courtesy of KIA MOTORS AMERICA, INC.

HCU MAIN FUNCTIONALITIES

Item	Functionality
Demand Torque Determination	Driver Creep Demand Torque Calculation Driver Acceleration/Deceleration Torque Calculation Driver Total Demand Torque Calculation
Regeneration Brake Control	Regeneration Brake Demand Torque Control Regeneration Brake Estimated Torque Calculation
EV/HEV Mode Determination	Engine Crank Condition Determination Engine Target Operating Status Determination
Battery SOC Balancing	Electric Power Limitation Charge/Discharge Power Determination Auxiliary System Power Limitation and Compensation
Engine Operating Point Determination	Engine Target Speed Determination in Idle Load Engine Target Torque Determination in Part Load Engine Target Torque Determination in Full Load Engine Target Torque Determination in Engine Stop or Passive Run
Idle/Racing Charge Control	Idle Charge Control Racing Charge Control
Engine Start/Stop Control	Crank Method Selection Speed Control for Cranking Engine Fuel Injection Control Engine Stop Control Engine Firing Complete Determination
Engine Clutch Engage/Slip/Release Control	Synch Engage Control Launch Engage Control Engine Brake Engage Control Engage in Shift Release Control
Torque Coordination Control	Engine Torque Determination in Transient State Motor Torque Determination in Transient State Generator Torque Determination in Transient State
Torque Invention Control	Torque Increase/Decrease Determination
Anti-Shock Control	Parabolic Torque Restriction Shift Assist Control Engine Clutch Slip Control Anti-jerk Control
System Limit Control	Battery Charge/Discharge Limit Control Engine, Hybrid Drive Motor, HSG Torque Limit Control
Torque Monitoring	Hybrid powertrain torque monitoring
Fail-Safe	Hybrid control system fail-safe control
Auxiliary System Control	Electric Oil Pump Control Variable Voltage Control of Low Voltage DC/DC A/C & Heater Control Brake Boost Control Cluster Display