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

2.4.3.6 Current and Position Sensing Power

The current and position sensing (resolver) is powered from the +12 V_LEM power rail. The LEM LF 510-S current transducers require symmetrical power supply of positive and negative 15 V.

The current draw for one current measurement channel from +/-15 V power supply is defined as (for details see LEM LF 510-S data sheet):

Equation 2. ICCLEM[mA]=44 mA+0.2 IMEAS[A]

Where 44 mA is the quiescent current of the transducer and IMEAS is the measured current. Peak measured current determines the maximum power draw. In our case we assume maximum 509 A of peak measured current (see note in the schematic diagram). This corresponds to 146 mA current consumption.

+15 V rail powers the resolver excitation amplifier. The current consumption naturally depends on the resolver type. Estimated current budget for this function is 150 mA from the +15 V rail.

A dual output SEPIC topology was selected to provide symmetrical 15V supply featuring LM5157-Q1. Similarly, as LM5158-Q1 this wide Vin converter has random spread spectrum for better noise performance. LM5157-Q1 simultaneously drives two independent SEPIC stages connected in series. To be able to use the LM5157/58 calculation spreadsheet for component calculation the total ILOAD must be determined. If we assume to be the VLOAD = 15 V we need to multiply the current transducer consumption by a factor of two. This represents two driven branches (creating the +/-15 V). ILOAD can be calculated as:

Equation 3. ILOAD=150 mA+2×3×146 mA=1026 mA

Where factor of three represents the three channels connected to the power supply and 150 mA represent the power budget for resolver excitation.

For component calculation in the calculation spreadsheet following parameters have been used:

Table 2-3 SEPIC Converter Design Parameters for Current and Position Sensing Circuits
Parameter Value
Min Nom Max Unit
VINPUT 8 12 16 V
fsw 435 kHz
VLOAD 15 V
ILOAD 0.35 A