Power Control System: Description and Operation

GF54.10-P-3012MEH Component Description For Battery Management System Control Unit

Component Identification:

Location
The battery management system control unit (N82/2) is integrated into the high-voltage battery module. The high-voltage battery module is located in the right rear of the engine compartment.

Interlock circuit
The interlock circuit is used for protecting people against accidental contact with high-voltage components. A 12 V/88Hz interlock signal is looped through all removable or high-voltage system components to be opened. To this end, each removable high-voltage plug connection has a contact bridge, which interrupts the interlock circuit when the high-voltage plug connection is removed. In addition to this, the interlock circuit is connected in series through the 12 V control unit plug connections for the high-voltage components.

Component Identification:

The temperature sensors for the high voltage battery cells (A100b2) are integrated into the high voltage battery.

Task
General
The battery management system control unit operates in an electrical network with the sensors and actuators to provide the battery management high voltage system.
The battery management constantly determines and monitors the following high voltage battery data:
- High voltage interlock
- Voltage
- Current flow
- Temperature
- Condition of protection switches

CAN data bus
The battery management system control unit is connected to the CAN interconnection of the vehicle via the drive train sensor CAN (CAN I) and exchanges data with other control units.

Input and output signals
The battery management system control unit evaluates the following input signals and issues the corresponding output signals:
^ Direct input signals
^ Direct output signals
^ CAN input signals
^ CAN output signals

Direct input signals
- Terminal 15
- Terminal 30
- Circuit 30c (CRASH signal from pyrotechnical separator (K88))
- Terminal 31
- High voltage interlock
- High-voltage battery cells temperature sensors
- High voltage 126 V+
- High voltage 126 V -

Direct output signals
- High-voltage battery cooling system shutoff valve (Y19/1)
- High voltage interlock
- High voltage 126 V+
- High voltage 126 V -

CAN input signals
Restraint system control unit (N2/7)
- Crash signal

ME-SFI [ME] control unit (N3/10)
- Engine hood closed/open
- Voltage exchange, high-voltage/12 V on-board electrical system
- Open/close protection switch

DC/DC converter control unit (N83/1)
- High voltage interlock

Power electronics control unit (N129/1)
- High voltage interlock
- Voltage and current values for integrated starter alternator (A79)

CAN output signals
ME-SFI [ME] control unit (N3/10)
- Protection switch status
- High-voltage battery open circuit voltage
- Voltage of high voltage battery
- Temperature of high voltage battery
- High-voltage battery currents
- Tolerable charging voltage/current
- Tolerable discharge voltage/current

Battery management system control unit (N82/2)
- high-voltage battery voltage values
- Power requirements

Central gateway control unit (N93)
- Diagnostic CAN (CAN-D) interface