Electric Drive Deactivation, Basic Function - GF08.00-P-1010A
Electric vehicles
Overview
This document contains information on:
- General
- Function requirements
- Electric drive deactivation
General
The shutdown path is used in the case of serious system failures (e.g. CAN network failure) to shut down the high-voltage on-board electrical system and the electric drive. The "drivetrain operational" status is retracted after powering down, and the vehicle is no longer ready to drive.
Function requirements
- Drive train operational
Electric drive deactivation
The deactivation function resets the "drivetrain operational" signal if, for example, one of the following conditions is met:
- Circuit 15 OFF
- Charging cable is plugged in
- Drive authorization is not granted
- CAN bus connection to high-voltage components is disrupted
- Level 2 of electric drive monitoring has been triggered
- High-voltage battery voltage is not in permissible range
- High-voltage battery temperature is not in permissible range
- Electric machine is not operational
- Contactor is open
Depending on the model, the opening of the contactor is permissible for a short time when switching between one-and two-circuit operation.
If the operational readiness of the electric machine is reset due to a short circuit or a signal failure in the output stage, the electric drive is only deactivated after 60 s.
Depending on the model, the user can switch off the vehicle while driving. To do this, the user must press the start/stop button for approx. three seconds or three times within three seconds.
If the deactivation function in the powertrain control unit detects a serious fault on the drive system, it requests the deactivation of the contactor. The battery management system control unit reports the successful deactivation of the contactor in the status signal. If the status signal fails, the powertrain control unit sets the status of the contactor to a substitute value internally.
If the contactor has been switched off due to a crash event, the powertrain control unit requests the active discharging of the capacitors in the high-voltage intermediate circuit by the power electronics control unit. The power electronics control unit checks the voltage value in the high-voltage intermediate circuit and reports the complete discharging when a minimum value is undershot. If this status signal fails, the powertrain control unit sets the status of the intermediate circuit discharging to a substitute value internally.
Following the successful deactivation of the high-voltage on-board electrical system, the powertrain control unit sets the status of the drivetrain to "not operational".
The powertrain control unit transmits this status via the networking so that the message indicating that the drivetrain is operational is no longer displayed to the driver.
| Function schematics | |||
| Function schematic for electric drive deactivation | Model 243 | PE08.00-P-2505-97A | |
| Model 295, 296, 297 | PE08.00-P-2505-97B | ||
| Additional basic functions | |||
| Power electronics control unit, basic function | GF08.20-P-9891A | ||
| Electric drive powertrain control unit, basic function | GF08.20-P-9892A |