TIDUF87 November   2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Current and Voltage Controller
      2. 2.2.2 DC/DC Start-Up
      3. 2.2.3 High-Resolution PWM Generation
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F28P650DK
      2. 2.3.2 ADS8588S
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software Requirements
      1. 3.2.1 Opening the Project Inside Code Composer Studio
      2. 3.2.2 Project Structure
      3. 3.2.3 Software Flow Diagram
    3. 3.3 Test Setup
      1. 3.3.1 Hardware Setup to Tune the Current and Voltage Loop
      2. 3.3.2 Hardware Setup to Test Bidirectional Power Flow
      3. 3.3.3 Hardware Setup for Current and Voltage Calibration
    4. 3.4 Test Procedure
      1. 3.4.1 Lab Variables Definitions
      2. 3.4.2 Lab 1. Open-Loop Current Control Single Phase
        1. 3.4.2.1 Setting Software Options for Lab 1
        2. 3.4.2.2 Building and Loading the Project and Setting up Debug Environment
        3. 3.4.2.3 Running the Code
      3. 3.4.3 Lab 2. Closed Loop Current Control Single Phase
        1. 3.4.3.1 Setting Software Options for Lab 2
        2. 3.4.3.2 Building and Loading the Project and Setting up Debug Environment
        3. 3.4.3.3 Running the Code
      4. 3.4.4 Lab 3. Open Loop Voltage Control Single Channel
        1. 3.4.4.1 Setting Software Options for Lab 3
        2. 3.4.4.2 Building and Loading the Project and Setting up Debug Environment
        3. 3.4.4.3 Running the Code
      5. 3.4.5 Lab 4. Closed Loop Current and Voltage Control Single Channel
        1. 3.4.5.1 Setting Software Options for Lab 4
        2. 3.4.5.2 Building and Loading the Project and Setting up Debug Environment
        3. 3.4.5.3 Running the Code
      6. 3.4.6 Lab 5. Closed Loop Current and Voltage Control Four Channels
        1. 3.4.6.1 Setting Software Options for Lab 5
        2. 3.4.6.2 Building and Loading the Project and Setting up Debug Environment
        3. 3.4.6.3 Running the Code
      7. 3.4.7 Calibration
    5. 3.5 Test Results
      1. 3.5.1 Current Loop Load Regulation
      2. 3.5.2 Current Loop Linearity Test
      3. 3.5.3 Voltage Loop Linearity Test
      4. 3.5.4 DCM Start-Up
      5. 3.5.5 Bidirectional Current Switching Time
      6. 3.5.6 Thermal Performance
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author

3.4.2.3 Running the Code

Use the following steps to run the code for Lab 1:

  1. Use the test setup shown in Figure 3-9.
  2. Run the project by clicking TIDA-010090 from the menu bar.
  3. In the watch view, check if the BT4H_InputVoltageSense_V is from 12V to 15V in the Expression Window.
  4. Check the BUSY signal of the external ADC if the frequency is 50kHz using an oscilloscope. Figure 3-13 shows the ADS8588S BUSY and CONVST signals when the MCU is running.
  5. Set the following parameters from the Expression Window:
    • BT4CH_userParam_chX->dutyRef_pu = 0.06
    • Set the BT4CH_userParam_chX->en_bool = 1
    • Set the BT4CH_userParam_chX->Relay_ON to 1 to enable the output relay
    • See Figure 3-14 for the Expression Window settings
  6. The BT4CH_measure_V_I_chX variable shows output current and voltage of the DC/DC converter. Adjust the BT4CH_userParam_chX->DutyRef_pu to make sure the current is approximately 15A.
  7. Figure 3-15 shows the SFRA setup to extract the plant model for Open-Loop Current Control. Click on the Run SFRA icon from the SYSCONFIG page. The SFRA GUI pops up.
  8. Select the options for the device on the SFRA GUI; for example, for F28P65x, select Floating Point. Click on the Setup Connection button. In the pop-up window, uncheck the boot-on-connect option and select an appropriate COM port. Click the OK button. Return to the SFRA GUI and click the Connect button.
  9. The SFRA GUI connects to the device. An SFRA sweep can now be started by clicking Start Sweep. The complete SFRA sweep takes a few minutes to finish. Once complete, a graph with the measurement appears, as shown in Figure 3-16.
  10. The Frequency Response Data is saved in the project folder, under an SFRA Data folder, and is time-stamped with the time of the SFRA run.
TIDA-010090 ADS8588S CONVST and BUSY SignalFigure 3-13 ADS8588S CONVST and BUSY Signal
TIDA-010090 Lab 1 Expression Window, Open LoopFigure 3-14 Lab 1 Expression Window, Open Loop
TIDA-010090 SFRA Setup for Open-Loop Current ControlFigure 3-15 SFRA Setup for Open-Loop Current Control
TIDA-010090 Current Control Open-Loop Frequency ResponseFigure 3-16 Current Control Open-Loop Frequency Response