TIDUF23 may   2023

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1  UCC5880-Q1
      2. 2.3.2  AM2634-Q1
      3. 2.3.3  TMS320F280039C-Q1
      4. 2.3.4  UCC14240-Q1
      5. 2.3.5  UCC12051-Q1
      6. 2.3.6  AMC3330-Q1
      7. 2.3.7  TCAN1462-Q1
      8. 2.3.8  ISO1042-Q1
      9. 2.3.9  ALM2403-Q1
      10. 2.3.10 LM5158-Q1
      11. 2.3.11 LM74202-Q1
    4. 2.4 System Design Theory
      1. 2.4.1 Microcontrollers
        1. 2.4.1.1 Microcontroller – C2000™
        2. 2.4.1.2 Microcontroller – Sitara™
      2. 2.4.2 Isolated Bias Supply
      3. 2.4.3 Power Tree
        1. 2.4.3.1 Introduction
        2. 2.4.3.2 Power Tree Block Diagram
        3. 2.4.3.3 12 V Distribution and Control
        4. 2.4.3.4 Gate Drive Supply
        5. 2.4.3.5 5-Volt Supply Domain
        6. 2.4.3.6 Current and Position Sensing Power
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
      1. 3.1.1 Hardware Board Overview
        1. 3.1.1.1 Control Board
        2. 3.1.1.2 MCU Control Card – Sitara™
        3. 3.1.1.3 MCU Control Card – C2000™
        4. 3.1.1.4 Gate Driver and Bias Supply Board
        5. 3.1.1.5 DC Bus Voltage Sense
        6. 3.1.1.6 SiC Power Module
          1. 3.1.1.6.1 XM3 SiC Power Module
          2. 3.1.1.6.2 Module Power Terminals
          3. 3.1.1.6.3 Module Signal Terminals
          4. 3.1.1.6.4 Integrated NTC Temperature Sensor
        7. 3.1.1.7 Laminated Busing and DC Bus Capacitors
          1. 3.1.1.7.1 Discharge PCB
    2. 3.2 Test Setup
      1. 3.2.1 Software Setup
        1. 3.2.1.1 Code Composer Studio Project
        2. 3.2.1.2 Software Structure
    3. 3.3 Test Procedure
      1. 3.3.1 Project Setup
      2. 3.3.2 Running the Application
    4. 3.4 Test Results
      1. 3.4.1 Isolated Bias Supply
      2. 3.4.2 Isolated Gate Driver
      3. 3.4.3 Inverter System
  9. 4General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines
  10. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 PCB Layout Recommendations
        1. 5.1.3.1 Layout Prints
      4. 5.1.4 Altium Project
      5. 5.1.5 Gerber Files
      6. 5.1.6 Assembly Drawings
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  11. 6Terminology

2.4.3.4 Gate Drive Supply

Low voltage domain of the isolated gate driver units (GDU) (UCC5880-Q1) is powered by the TPS7B6933-Q1 LDO. The high-voltage (HV) domain of the GDU is powered using UCC14240-Q1 isolated DC/DC modules. These modules were selected for their compactness and ease of use.

The voltage generated by UCC14240-Q1 is set to total 19 V ( VCC2 = 15 V and VEE2 = -4 V ). The high-voltage negative pole is a virtual ground for UCC14240-Q1.

The maximum power consumption on the high-voltage side of each UCC14240-Q1 DC/DC module can be estimated as a worst-case switching condition for fSWmax = 30 kHz and CL = 100 nF:

Equation 1. P2=fSWmax(VCC2-VEE2)2CL+(VCC2-VEE2)ICCq2

The secondary quiescent current of UCC5880-Q1 can be found in the data sheet as ICC2q = 15 mA. Resulting secondary power consumption is then calculated as 1.368 W. Assuming 50% efficiency this corresponds to 114 mA of supply current on 24-volt input side of each UCC14240-Q1.

These UCC14240-Q1 DC/DC modules require pre-regulated 24 V. 24-volt pre-regulator is implemented as LM5158-Q1 based SEPIC with coupled inductors. The SEPIC topology supports appropriate input voltage range and the LM5157/8-Q1 converters are designed for in this case because of their versatility and due to random spread spectrum also for the noise properties.

The component values for the power supply design were calculated using the LM5158 Quick Start Calculator tool for SEPIC. The main input parameters of the supply are shown in Table 2-2.

Table 2-2 SEPIC Converter Design Parameters for Gate Drive Power Supply
Parameter Value
Min Nom Max Unit
VINPUT 8 12 16 V
fsw 435 kHz
VLOAD 24 V
ILOAD 0.35 A

Each 24-volt SEPIC powers three UCC14240-Q1 therefore ILOAD = 0.35A is listed (see Figure 2-5).