TIDUEY0A November   2020  – December 2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Li-ion Cell Formation Equipment
    2. 1.2 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 System Design Theory
      1. 2.2.1 Feedback Controller
      2. 2.2.2 DC/DC Start-Up
      3. 2.2.3 High-Resolution PWM Generation
      4. 2.2.4 Output Inductor and Capacitor Selection
      5. 2.2.5 Current and Voltage Feedback
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F28P650DK
      2. 2.3.2 ADS9324
      3. 2.3.3 INA630
      4. 2.3.4 UCC27284
      5. 2.3.5 REF50E
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software
      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 Test Bidirectional Power Flow
      2. 3.3.2 Hardware Setup to Tune the Current and Voltage Loop
      3. 3.3.3 Hardware Setup for Current and Voltage Calibration
      4. 3.3.4 Lab Variables Definitions
      5. 3.3.5 Test Procedure
        1. 3.3.5.1 Lab 1. Open-Loop Current Control Single Phase
          1. 3.3.5.1.1 Setting Software Options for Lab 1
          2. 3.3.5.1.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.1.3 Running the Code
        2. 3.3.5.2 Lab 2. Closed Loop Current Control Single Channel
          1. 3.3.5.2.1 Setting Software Options for Lab 2
          2. 3.3.5.2.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.2.3 Run the Code
        3. 3.3.5.3 Lab 3. Open Loop Voltage Control Single Channel
          1. 3.3.5.3.1 Setting Software Options for Lab 3
          2. 3.3.5.3.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.3.3 Running the Code
        4. 3.3.5.4 Lab 4. Closed Loop Current and Voltage Control Single Channel
          1. 3.3.5.4.1 Setting Software Options for Lab 4
          2. 3.3.5.4.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.4.3 Running the Code
        5. 3.3.5.5 Lab 5. Closed Loop Current and Voltage Control Four Channels
          1. 3.3.5.5.1 Setting Software Options for Lab 5
          2. 3.3.5.5.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.5.3 Running the Code
        6. 3.3.5.6 Calibration
    4. 3.4 Test Results
      1. 3.4.1 Current Load Regulation
      2. 3.4.2 Voltage Load Regulation
      3. 3.4.3 Current Linearity Test
      4. 3.4.4 Voltage Loop Linearity Test
      5. 3.4.5 Bidirectional Current Switching Time
      6. 3.4.6 Current Step Response
  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
  12. 6Revision History
3.3.5.1.3 Running the Code

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

  1. Use the test setup shown in Section 3.3.2.
  2. Run the project by clicking TIDA-010086 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 DRDY signal of the external ADC if the frequency is 50kHz using an oscilloscope. Figure 3-13 shows the ADS9324 DRDY and CONVST signals when the MCU is running.
  5. Set the following parameters from the Expression Window:
    • BT4CH_userParam_chX->dutyRef_pu = 0.02
    • 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 4.5A.
  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.
  11. After finishing the lab, set the following parameters from the Expression Window to stop the code:
    • BT4CH_userParam_chX->dutyRef_pu = 0
    • Set the BT4CH_userParam_chX->en_bool = 0
    • Set the BT4CH_userParam_chX->Relay_ON to 0 to disable the output relay
    • Terminate the program
TIDA-010086 ADS9324 CONVST and DRDY Signal Figure 3-13 ADS9324 CONVST and DRDY Signal
TIDA-010086 Lab 1 Expression Window, Open Loop Figure 3-14 Lab 1 Expression Window, Open Loop
TIDA-010086 SFRA Setup for Open-Loop Current Control Figure 3-15 SFRA Setup for Open-Loop Current Control
TIDA-010086 Current Control Open-Loop Frequency Response Figure 3-16 Current Control Open-Loop Frequency Response