Description

High Voltage Control System Description

• The high voltage battery control system consists of the Battery Management Unit (BMU), the Cell Monitoring Unit (CMU) and the Power Relay Assembly (PRA).-BMU : It controls the high voltage relay in the battery system and communicates with the other parts or control units in a vehicle.-CMU : It measures the high voltage battery module temperature, voltage, etc. and sends the data to BMU.-PRA : It consists of the relays (main relay, pre-charge relay and PTC heat relay, etc.) controlled by the BMU and the battery current sensor.

• It controls the SOC, power, fault diagnosis, battery cell balancing and supplying and shutting the power.

Function

1. SOC Control : It controls to proper range by calculating the SOC through measuring the voltage, current, and temperature.2. Battery output control : It maximizes the battery protection, available power prediction and charge/discharge energy by calculating the input/output energy values according to system state. It also prevents overcharge/over discharge.3. Relay control : It supplies and shuts the power off to system related to high voltage and high voltage system, and prevents safety accidents by shutting the relay off in case of failure.4. Heating control : It maintains the best battery operating temperature through 3 way valve, Electric Water Pump (EWP) control, PTC heater control (optional).5. Fault Diagnosis : Diagnose system faults and classify fail-safe levels to prevent safety accidents through output restrictions or relay control.

   

• SOC (State Of Charge) : Level of charge of an battery relative to its capacity

• SOC = (Dischargeable current / Battery rated capacity) X 100%

High Voltage Control System Logic