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Component Description For Power Electronics Control Unit - GF08.20-P-1001GRH

Engine 276.821 in model 166 

Fig 1: Power Electronics Control Unit Components Location - Engine 276.821 In Model 166 (Shown On Model 166.063)
G14134066Courtesy of MERCEDES-BENZ USA

Shown on model 166.063 

Shown: power electronics control unit 

Location 

The power electronics control unit is located on the underfloor in the vicinity of the front passenger seat.

G14134067Courtesy of MERCEDES-BENZ USA

Shown on high-voltage distributor plate (F34/6) with electrical fuses 

G14134068Courtesy of MERCEDES-BENZ USA

Structure 

In the power electronics control unit there is the power inverter for actuation of the electrical machine.

IMPORTANT Interlock circuit

The interlock circuit is used as contact protection to protect people against inadvertent contact with high-voltage components. The interlock is an anticipatory contact which opens a little before the high-voltage connection when opening a high-voltage connection. In this way timely discharging of the high voltage intermediate circuit is achieved by the control units of the high-voltage components.

In order to do this, a 12 V/88 Hz interlock signal is looped through all high voltage on-board electrical system assembly parts that can be removed or opened. To do this there is an electrical bridge in each removable high-voltage connection which interrupts the interlock circuit during removal of the high-voltage connection. The interlock circuit is also led switched in a series over the 12 V control units plug connection of the high-voltage components.

Task 

General 

The power electronics control unit actuates the electric machine (A79/1) upon request of the ME-SFI [ME] control unit (N3/10) with 3-phase AC voltage. It monitors the temperature and position of the electrical machine and provides diagnoses and forecasts about the available torque to the ME-SFI [ME] control unit.

Coding 

The power electronics control unit is flashable which means that the complete software in the control unit can be updated.

CAN network 

The power electronics control unit is connected via the hybrid CAN (CAN L) to the vehicle CAN network and exchanges data with other control units.

Input and output signals 

Input factors and initial parameters for the following components are read in or output over direct lines by the power electronics control unit and are needed by the engine timing:

Input factors over a direct line Initial parameters over a direct line Supplemental information
Circuit 30c (crash signal from battery compartment prefuse box (F33) - -
Circuit 30 - -
Circuit 31 - -
Circuit 50 (shut down) from control unit ME - -
Circuit 87f - -
Engine speed signal (internal combustion engine) - TNA
Interlock circuit Interlock circuit -
Electrical machine rotor position sensor (L20) Power supply for electrical machine rotor position sensor (L20) -
Electrical machine temperature sensor (A79/1b1) Electrical machine temperature sensor power supply (A79/1b1) -

The following components are connected over output connections with the power electronics control unit:

Output connections + Output connections - Supplemental information
High-voltage battery (A100g1) (discharge current) High-voltage battery (A100g1) (discharge current) -
High-voltage battery (A100g1) (charging current High-voltage battery (A100g1) (charging current) -
  Phase U (actuation for engine operation mode, charging current from alternator operation mode Electrical machine (A79/1)  
- Phase U (actuation for engine operation mode, charging current from alternator operation mode Electrical machine (A79/1) -
  Phase W (actuation for engine operation mode, charging current from alternator operation mode Electrical machine (A79/1)  
High-voltage connection for battery management system control unit (N82/2) High-voltage connection for battery management system control unit (N82/2) -
High voltage positive temperature coefficient heater high-voltage connection (N33/5) High voltage positive temperature coefficient heater high-voltage connection (N33/5) -
Electrical A/C compressor high-voltage connection (A9/5) Electrical A/C compressor high-voltage connection (A9/5) -

Input factors and initial parameters for the following components and control units are sent or received by the power electronics control unit via the CAN:

Input factors via hybrid CAN (CAN L) Starting data via hybrid CAN (CAN L) Supplemental information
Battery management system control unit (N82/2) Battery management system control unit (N82/2 -
DC/DC converter control unit (N83/1) DC/DC converter control unit (N83/1) -
Charger (N83/5) Charger (N83/5) -
Powertrain control unit (N127) Powertrain control unit (N127) Contained signals of further control units which are connected via the CAN network.