SDAA370 May   2026 UCC34141

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 End-Equipment Traction Inverter
    2. 1.2 Why is Safety Needed in Inverter?
    3. 1.3 FuSa Development Flow
      1. 1.3.1 V-Model Development
      2. 1.3.2 Inverter Safety Lifecycle
  5. 2FuSa Requirements for Traction Inverter
    1. 2.1 Traction Inverter Structure and Function Introduction
    2. 2.2 FuSa Requirements Derivation Process
    3. 2.3 Safety Goal
    4. 2.4 FuSa Concept
      1. 2.4.1 FSC Design Architecture
      2. 2.4.2 Fault Tree Analysis
      3. 2.4.3 FuSa Requirement
    5. 2.5 Technical Safety Concepts
      1. 2.5.1 TSC Design Architecture
      2. 2.5.2 Failure Mode and Effect Analysis
      3. 2.5.3 Technical Safety Requirements
  6. 3Safety Design Implementation on Inverter
    1. 3.1 TI FuSa Product
    2. 3.2 How Does TSR Implement?
      1. 3.2.1 Position Sensor
      2. 3.2.2 MCU
      3. 3.2.3 Logic Circuit
      4. 3.2.4 Smart Isolated Gate Driver
    3. 3.3 Dependent Failure Consideration
    4. 3.4 Detailed FuSa Design Structure for Traction Inverter
    5. 3.5 Achieving FuSa Requirements with TI Safety Devices
      1. 3.5.1 MCU
      2. 3.5.2 Gate Driver
        1. 3.5.2.1 Gate Monitor Circuit and Over Current Protection
        2. 3.5.2.2 Other Safety Mechanisms in UCC5881-Q1
      3. 3.5.3 Isolated bias supply
        1. 3.5.3.1 Centralized LV Isolated Power Supply Architecture
        2. 3.5.3.2 Fully Distributed LV Isolated Power Supply Architecture
        3. 3.5.3.3 Semi-Distributed LV Isolated Power Supply Architecture
        4. 3.5.3.4 HV Isolated Bias Supply
        5. 3.5.3.5 TI's Design for Isolated Bias Supply in Traction Inverter
      4. 3.5.4 Power Management IC
        1. 3.5.4.1 Multiple Paths Power Rail with Protection and Independent Thermal Shut-Down
        2. 3.5.4.2 Power Rail Voltage Monitoring
        3. 3.5.4.3 MCU Fault Monitor and other Protection Mechanisms
      5. 3.5.5 Position Sensor
      6. 3.5.6 Current Sensor
      7. 3.5.7 Voltage Sensor
        1. 3.5.7.1 Isolated DC Voltage Sensing
        2. 3.5.7.2 Non-Isolated DC voltage sensing
      8. 3.5.8 Temperature Sensor
  7. 4Summary
  8. 5References

2.1 Traction Inverter Structure and Function Introduction

The primary goal of the traction system is to efficiently drive the traction motor, typically the permanent magnet synchronous motor (PMSM), with high control bandwidth. The Field-Oriented Control (FOC) algorithm is implemented in the Microcontroller Unit (MCU) to generate corresponding PWM signals, which control the gate driver to preciously switch the power module, converting the DC input voltage from the high-voltage (HV) battery into three-phase symmetric AC currents to drive the PMSM. Figure 2-1 shows the block diagram of a traction inverter.

For the FOC algorithm, the system requires real-time measurement of phase currents, rotor position, and DC-link input voltage. This requires high-accuracy, low-latency sensors within the traction inverter. Additionally, high-reliability power management components are essential to supply all elements in the system.

Since the isolation is required between the HV side and low-voltage (LV) side, isolated gate drivers with reliable isolated power supply circuits are necessary elements. Through CAN transceivers, the traction inverter accurately receives command of driving torque and reports any potential fault information to the Vehicle Control Unit (VCU). During braking operations, the traction inverter can operate in regeneration mode to charge the battery while simultaneously generating braking torque.

Block Diagram of a Traction Inverter Figure 2-1 Block Diagram of a Traction Inverter