Quickly understand the high voltage structure and principle of Audi E-tron models

Based on the Audi original self-study materials, this article uses diagrams to share with you the structure and function of the high-voltage components of the Audi new Q2L E-tron. Understand and recognize the structure of the electric drive system of the Audi Q2L model from a basic level, and prepare for the basic maintenance work. I hope that this article can help you quickly understand the high-voltage structure and principle of the Audi E-tron model.

1. Overview of high voltage components

1. Connection diagram of high voltage system

2. Overview of high voltage system connection wires

2. High voltage components

1. High voltage charging interface

DC charging interface UX4

AC charging port UX5

2. High voltage charger AX4

2.1 The pulse inverter converts AC power into DC power and supplies it to the high-voltage battery. 2.2 High-voltage charger control unit J1050

3. High voltage heater Z115

3.1 Heating the coolant and providing warm air to the vehicle 3.2 Control unit J848

4. Air conditioning compressor V470

4.1 Electric compressor V470 activated by the climate control unit J255 4.2 Control unit J842

5. Power electronics device JX1

Electric drive system control unit J841

Air conditioning compressor fuse S355

Inverter A37

Transformer A19

C25

High voltage wire

12V vehicle power grid interface

Coolant connection

Structure description: A37: DC/AC, AC/DC A19: High voltage DC/Low voltage DC

Electric drive system control unit J841

The motor rotor position sensor G713 detects the position of the traction motor V141.

The motor temperature sensor G712 detects the temperature of the traction motor V141.

Detect the temperature of JX1 internal components through the JX1 internal temperature sensor

JX1 master control function

5.1 Discharge process of power electronic device JX1: (1) Active discharge

Terminal 15 is disconnected, a collision occurs, and the safety line is opened. A19 is used to reduce the high voltage to 60V within 4 seconds. (2) Emergency discharge

When A19 is damaged, the discharge resistor performs emergency discharge for about 4 seconds. (3) Passive discharge With the help of the resistor of JX1, passive discharge is achieved, which lasts for 120 seconds. This process exists at any time. 5.2 Functional status description of power electronic device JX1 (1) Electrical idling function

Terminal 15 is disconnected, the vehicle can move at walking speed. Terminal 15 is connected and in N gear, idling is switched to a maximum of about 50km/h. (2) Active short circuit

Terminal 15 is disconnected, the moving speed exceeds the walking speed. Terminal 15 is connected and the moving speed exceeds 50km/h. There will be greater mechanical resistance when actively short-circuited.

6. Three-phase AC drive motor VX54

The motor structure consists of: Electric traction motor V141 Traction motor temperature sensor G712 Traction motor rotor position sensor G713 Two coolant interfaces and three phase interfaces

6.1 V141 as an electric motor

The A37 converts DC into three-phase AC to adjust the speed by changing the frequency and adjust the torque by changing the on-time of a single pulse width. The 6.2 V141 acts as a generator

A37 converts the generated three-phase AC power into DC power transformer A19 converts the high-voltage DC power into 12V DC power for use in the vehicle power grid

7. High voltage battery switch box SX6

7.1 Composition of high voltage battery switch box SX6

High voltage battery current sensor G848

High voltage battery power protector 1 J1057, HV positive

High voltage battery power protector 2 J1058, HV negative

High voltage battery pre-charge protector J1044, HV positive

High voltage DC charging contactor 1 J1052, positive

High voltage DC charging contactor 2 J1053, negative

High voltage battery protection resistor N662

High voltage system fuse S350

High voltage system capacitors

J840

7.2 High voltage battery switch box SX6 charging structure

Conditions for opening the power protector contactor

Terminal 15 closed

The airbag control unit J234 sends a crash signal via the data bus

Airbag control unit J234 sends crash signal via discrete wires

Maintenance plug TW open

Power protector terminal 30C power supply fuse is damaged

The 12 V supply to the hybrid battery unit J840 is interrupted

Security line interrupted

8. High voltage battery AX2

Vehicle underfloor

The battery module consists of 16 modules, and every 8 modules are connected to 1 battery module control unit. 192 cells, 6S2P are combined into 1 module, and the module voltage is 22V.

High voltage battery AX2 control unit

Control unit J840

Monitoring safety line

Monitoring collision signals

Main control functions of battery monitoring control units J1208 and J1209

Control protection relay

Charge state regulation

Insulation protection device monitoring

Measuring the current before and after the protection relay

3. High voltage system connection relationship

4. Low voltage control components Maintenance plug TW

30C power supply fuse