SPRUJF4A October   2024  – December 2024

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
    5.     General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines
  7. 2Hardware
    1. 2.1 Hardware Description
      1. 2.1.1 Auxiliary Power Supply
      2. 2.1.2 DC Link Voltage Sensing
      3. 2.1.3 Motor Phase Voltage Sensing
      4. 2.1.4 Motor Phase Current Sensing
        1. 2.1.4.1 Three-Shunt Current Sensing
        2. 2.1.4.2 Single-Shunt Current Sensing
      5. 2.1.5 External Overcurrent Protection
      6. 2.1.6 Internal Overcurrent Protection for TMS320F2800F137
    2. 2.2 Getting Started Hardware
      1. 2.2.1 Test Conditions and Equipment
      2. 2.2.2 Test Setup
  8. 3Motor Control Software
    1. 3.1 Three-Phase PMSM Drive System Design Theory
      1. 3.1.1 Field-Oriented Control of PMSM
        1. 3.1.1.1 Space Vector Definition and Projection
          1. 3.1.1.1.1 ( a ,   b ) ⇒ ( α , β ) Clarke Transformation
          2. 3.1.1.1.2 ( α , β ) ⇒ ( d ,   q ) Park Transformation
        2. 3.1.1.2 Basic Scheme of FOC for AC Motor
        3. 3.1.1.3 Rotor Flux Position
      2. 3.1.2 Sensorless Control of PM Synchronous Motor
        1. 3.1.2.1 Enhanced Sliding Mode Observer With Phase-Locked Loop
          1. 3.1.2.1.1 Mathematical Model and FOC Structure of an IPMSM
          2. 3.1.2.1.2 Design of ESMO for the IPMS
            1. 3.1.2.1.2.1 Rotor Position and Speed Estimation With PLL
      3. 3.1.3 Field Weakening (FW) and Maximum Torque Per Ampere (MTPA) Control
    2. 3.2 Getting Started Software
      1. 3.2.1 GUI
      2. 3.2.2 Download and Install C2000 Software
      3. 3.2.3 Using the Software
      4. 3.2.4 Project Structure
  9. 4Test Procedure and Results
    1. 4.1 Build Level 1: CPU and Board Setup
    2. 4.2 Build Level 2: Open-Loop Check With ADC Feedback
    3. 4.3 Build Level 3: Closed Current Loop Check
    4. 4.4 Build Level 4: Full Motor Drive Control
    5. 4.5 Test Procedure
      1. 4.5.1 Startup
      2. 4.5.2 Build and Load Project
      3. 4.5.3 Setup Debug Environment Windows
      4. 4.5.4 Run the Code
        1. 4.5.4.1 Build Level 1 Test Procedure
        2. 4.5.4.2 Build Level 2 Test Procedure
        3. 4.5.4.3 Build Level 3 Test Procedure
        4. 4.5.4.4 Build Level 4 Test Procedure
          1. 4.5.4.4.1 Tuning Motor Drive FOC Parameters
          2. 4.5.4.4.2 Tuning Field Weakening and MTPA Control Parameters
          3. 4.5.4.4.3 Tuning Current Sensing Parameters
    6. 4.6 Performance Data and Results
      1. 4.6.1 Load and Thermal Test
      2. 4.6.2 Overcurrent Protection by External Comparator
      3. 4.6.3 Overcurrent Protection by Internal CMPSS
  10. 5Hardware Design Files
    1. 5.1 Schematics
    2. 5.2 PCB Layouts
    3. 5.3 Bill of Materials (BOM)
  11. 6Additional Information
    1. 6.1 Known Hardware or Software Issues
    2. 6.2 Trademarks
    3. 6.3 Terminology
  12. 7References
  13. 8Revision History

2.1.4.2 Single-Shunt Current Sensing

The single-shunt current-sensing technique measures the DC-link bus current, with knowledge of the power FET switching states and reconstructs the three-phase current of the motor. The detailed description of the single shunt technique is described in the Sensorless-FOC for PMSM With Single DC-Link Shunt application note.

On this reference board, implement the single-shunt current-sensing technique by removing two shunts and shorting the connection of the U, V, W ground of the power module as shown in Figure 2-8.

TIEVM-MTR-HVINV Single-Shunt Current-Sensing Resistor Configuration Figure 2-8 Single-Shunt Current-Sensing Resistor Configuration
  1. On the motherboard, remove current shunt resistors R81, and R82, just keep only shunt resistor R80 to sense the DC-Link current.
  2. On the TMS320F2800137 daughterboard, remove C23 to increase U3A bandwidth for single-shunt sampling.
  3. Use a thick wire to connect the NU, NV, and NW pins together.
TIEVM-MTR-HVINV Single-Shunt Current-Sensing Circuit for TMS320F2800137Figure 2-9 Single-Shunt Current-Sensing Circuit for TMS320F2800137

By default, the board has three shunt resistors. Figure 2-10 shows the layout of the shunt resistors. To implement single-shunt resistor sensing, remove R81 and R82 while keeping R80. Solder NU, NV and NW (pin 2 of R80, R81, and R82) together. All three phase currents now flow through only R80.

TIEVM-MTR-HVINV Shunt Resistors LayoutFigure 2-10 Shunt Resistors Layout

The DC-Link current is a unidirectional signal, so the DC current offset can be set to a minimum or maximum value to improve the ADC sampling range for the DC-Link current as Figure 2-11 shows. On the TMS320F2800137 daughterboard, change R23 from 10 kΩ to 1 kΩ/1% resistor for the reference voltage to have 0.3-V offset for DC current sensing.

TIEVM-MTR-HVINV DC Offset Reference for Single Shunt of TMS320F2800137 DaughterboardFigure 2-11 DC Offset Reference for Single Shunt of TMS320F2800137 Daughterboard

The transfer function of this current sampling circuit and the calculation for single shunt are the same as for three shunt.