TIDUF77 June   2024 MSPM0G1507

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Terminology
    2. 1.2 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F2800137
      2. 2.3.2 MSPM0G1507
      3. 2.3.3 DRV7308
      4. 2.3.4 UCC28911
      5. 2.3.5 TLV9062
      6. 2.3.6 TLV74033
      7. 2.3.7 ISO6721B
      8. 2.3.8 TMP6131
    4. 2.4 System Design Theory
      1. 2.4.1 Hardware Design
        1. 2.4.1.1 Modular Design
        2. 2.4.1.2 Auxiliary Flyback Power Supply
        3. 2.4.1.3 DC Link Voltage Sensing
        4. 2.4.1.4 Inrush Current Protection
        5. 2.4.1.5 Motor Phase Voltage Sensing
        6. 2.4.1.6 Motor Phase Current Sensing
        7. 2.4.1.7 Over Current Protection of DRV7308
        8. 2.4.1.8 Internal Overcurrent Protection for TMS320F2800F137
      2. 2.4.2 Three-Phase PMSM Drive
        1. 2.4.2.1 Field-Oriented Control of PM Synchronous Motor
          1. 2.4.2.1.1 Space Vector Definition and Projection
            1. 2.4.2.1.1.1 ( a ,   b ) ⇒ ( α , β ) Clarke Transformation
            2. 2.4.2.1.1.2 α , β ⇒ ( d ,   q ) Park Transformation
          2. 2.4.2.1.2 Basic Scheme of FOC for AC Motor
          3. 2.4.2.1.3 Rotor Flux Position
        2. 2.4.2.2 Sensorless Control of PM Synchronous Motor
          1. 2.4.2.2.1 Enhanced Sliding Mode Observer With Phase-Locked Loop
            1. 2.4.2.2.1.1 Mathematical Model and FOC Structure of an IPMSM
            2. 2.4.2.2.1.2 Design of ESMO for the IPMSM
            3. 2.4.2.2.1.3 Rotor Position and Speed Estimation With PLL
        3. 2.4.2.3 Field Weakening (FW) and Maximum Torque Per Ampere (MTPA) Control
        4. 2.4.2.4 Hardware Prerequisites for Motor Drive
          1. 2.4.2.4.1 Motor Current Feedback
            1. 2.4.2.4.1.1 Three-Shunt Current Sensing
            2. 2.4.2.4.1.2 Single-Shunt Current Sensing
          2. 2.4.2.4.2 Motor Voltage Feedback
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Getting Started Hardware
      1. 3.1.1 Hardware Board Overview
      2. 3.1.2 Test Conditions
      3. 3.1.3 Test Equipment Required for Board Validation
    2. 3.2 Getting Started GUI
      1. 3.2.1 Test Setup
      2. 3.2.2 Overview of GUI Software
      3. 3.2.3 Setup Serial Port
      4. 3.2.4 Motor Identification
      5. 3.2.5 Spin Motor
      6. 3.2.6 Motor Fault Status
      7. 3.2.7 Tune Control Parameters
      8. 3.2.8 Virtual Oscilloscope
    3. 3.3 Getting Started C2000 Firmware
      1. 3.3.1 Download and Install Software Required for Board Test
      2. 3.3.2 Opening Project Inside CCS
      3. 3.3.3 Project Structure
      4. 3.3.4 Test Procedure
        1. 3.3.4.1 Build Level 1: CPU and Board Setup
          1. 3.3.4.1.1 Start CCS and Open Project
          2. 3.3.4.1.2 Build and Load Project
          3. 3.3.4.1.3 Setup Debug Environment Windows
          4. 3.3.4.1.4 Run the Code
        2. 3.3.4.2 Build Level 2: Open-Loop Check With ADC Feedback
          1. 3.3.4.2.1 Start CCS and Open Project
          2. 3.3.4.2.2 Build and Load Project
          3. 3.3.4.2.3 Setup Debug Environment Windows
          4. 3.3.4.2.4 Run the Code
        3. 3.3.4.3 Build Level 3: Closed Current Loop Check
          1. 3.3.4.3.1 Start CCS and Open Project
          2. 3.3.4.3.2 Build and Load Project
          3. 3.3.4.3.3 Setup Debug Environment Windows
          4. 3.3.4.3.4 Run the Code
        4. 3.3.4.4 Build Level 4: Full Motor Drive Control
          1. 3.3.4.4.1 Start CCS and Open Project
          2. 3.3.4.4.2 Build and Load Project
          3. 3.3.4.4.3 Setup Debug Environment Windows
          4. 3.3.4.4.4 Run the Code
          5. 3.3.4.4.5 Tuning Motor Drive FOC Parameters
          6. 3.3.4.4.6 Tuning Field Weakening and MTPA Control Parameters
          7. 3.3.4.4.7 Tuning Current Sensing Parameters
    4. 3.4 Test Results
      1. 3.4.1  Fast and clean Rising/Falling Edge
      2. 3.4.2  Inrush Current Protection
      3. 3.4.3  Thermal performance under 300VDC
      4. 3.4.4  Thermal performance under 220VAC
      5. 3.4.5  Overcurrent Protection by Internal CMPSS
      6. 3.4.6  IPM Efficiency with External Bias Supply under 300VDC
      7. 3.4.7  Board Efficiency with Onboard Bias Supply under 300VDC
      8. 3.4.8  Board Efficiency with External Bias Supply under 220VAC
      9. 3.4.9  Board Efficiency with Onboard Bias Supply under 220VAC
      10. 3.4.10 iTHD Test of Motor Phase Current
      11. 3.4.11 Standby Power Test
    5. 3.5 Migrate Firmware to a New Hardware Board
      1. 3.5.1 Configure the PWM, CMPSS, and ADC Modules
      2. 3.5.2 Setup Hardware Board Parameters
      3. 3.5.3 Configure Faults Protection Parameters
      4. 3.5.4 Setup Motor Electrical Parameters
    6. 3.6 Getting Started MSPM0 Firmware
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 Bill of Materials
      3. 4.1.3 PCB Layout Recommendations
      4. 4.1.4 Altium Project
      5. 4.1.5 Gerber Files
    2. 4.2 Software Files
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author
3.3.4.4.7 Tuning Current Sensing Parameters

Accurate current sensing is important to estimate the rotor angle and speed, and also have the best dynamic motor control. The current sensing parameters must match the hardware by setting the following related parameters:

  • Dead-band time, the rising edge delay time must be greater than (high-side turn on time) + (low side turn-off time) of the power module, and the falling edge delay time must be greater than (high-side turn-off time) + (low-side turn-on time) of the power module as shown in the following setting for a power module used in the reference design.
//! \brief Defines the PWM deadband falling edge delay count (system clocks)
#define MTR1_PWM_DBFED_CNT (uint16_t)(2.5f * 120.0f)  // 2.5us, (>2.0us)

//! \brief Defines the PWM deadband rising edge delay count (system clocks)
#define MTR1_PWM_DBRED_CNT (uint16_t)(2.5f * 120.0f)  // 2.50us, (>2.0us)
  • Minimum duration of pulse width PWM, specifies to be greater than (Hardware delay time + Dead band time + Ringing duration + ADC sampling time).
//! \brief Defines the minimum duration, Clock Cycle
#define USER_M1_DCLINKSS_MIN_DURATION   (450U)
  • Sample and hold delay time, specifies the time delay from PWM output to ADC sample time for current sensing. The delay time is dependent on the hardware and includes the propagation delay of the gate driver circuit and turn on and turn off delay of the power FET, and is less than or equal to (Minimum duration – ADC sampling time).
//! \brief Defines the sample delay, Clock Cycle

#define USER_M1_DCLINKSS_SAMPLE_DELAY   (430U)