TIDUFB1 December   2024

 

  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
      1. 2.2.1 Control System Design Theory
        1. 2.2.1.1 PWM Modulation
        2. 2.2.1.2 Current Loop Model
        3. 2.2.1.3 DC Bus Regulation Loop
        4. 2.2.1.4 DC Voltage Balance Controller
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F280013x
      2. 2.3.2 UCC5350
      3. 2.3.3 AMC1350
      4. 2.3.4 TMCS1123
      5. 2.3.5 UCC28750
      6. 2.3.6 LM25180
      7. 2.3.7 ISOTMP35
      8. 2.3.8 TLV76133
      9. 2.3.9 TLV9062
    4. 2.4 Hardware Design
      1. 2.4.1  Inductor Design
      2. 2.4.2  Bus Capacitor Selection
      3. 2.4.3  Input AC Voltage Sensing
      4. 2.4.4  Output DCBUS Voltage Sensing
      5. 2.4.5  Auxiliary Power Supply
      6. 2.4.6  Isolated Power Supply
      7. 2.4.7  Inductor Current Sensing
      8. 2.4.8  Gate Driver
      9. 2.4.9  Isolated Temperature Sensing
      10. 2.4.10 Overcurrent, Overvoltage Protection (CMPSS)
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
      1. 3.1.1 Getting Started Hardware
        1. 3.1.1.1 Board Overview
        2. 3.1.1.2 Test Equipment
    2. 3.2 Software Requirements
      1. 3.2.1 Getting Started GUI
        1. 3.2.1.1 Test Setup
        2. 3.2.1.2 Overview of a GUI Software
        3. 3.2.1.3 Procedures of Test With GUI
      2. 3.2.2 Getting Started Firmware
        1. 3.2.2.1 Opening the Project Inside Code Composer Studio™
        2. 3.2.2.2 Project Structure
        3. 3.2.2.3 Test Setup
        4. 3.2.2.4 Running Project
          1. 3.2.2.4.1 INCR_BUILD 1: Open Loop
            1. 3.2.2.4.1.1 Setting, Building, and Loading the Project
            2. 3.2.2.4.1.2 Setup Debug Environment Windows
            3. 3.2.2.4.1.3 Using Real-Time Emulation
            4. 3.2.2.4.1.4 Running Code (Build 1)
          2. 3.2.2.4.2 INCR_BUILD 2: Closed Current Loop
            1. 3.2.2.4.2.1 Running Code (Build 2)
            2. 3.2.2.4.2.2 Building and Loading the Project and Setting Up Debug
          3. 3.2.2.4.3 INCR_BUILD 3: Closed Voltage and Current Loop
            1. 3.2.2.4.3.1 Building and Loading the Project and Setting Up Debug
            2. 3.2.2.4.3.2 Running Code (Build 3)
          4. 3.2.2.4.4 INCR_BUILD 4: Closed Balance, Voltage, and Current Loop
            1. 3.2.2.4.4.1 Building and Loading the Project and Setting Up Debug
            2. 3.2.2.4.4.2 Running Code (Build 4)
    3. 3.3 Test Results
      1. 3.3.1  IGBT Gate Rising and Falling Time
      2. 3.3.2  Power On Sequence
      3. 3.3.3  PFC Started by GUI
      4. 3.3.4  Zero Crossing Under 380VAC, 9kW
      5. 3.3.5  Current Ripple Under 380VAC,10kW
      6. 3.3.6  10kW Load Test With Grid Power
      7. 3.3.7  9kW Load Test With AC Power Source
      8. 3.3.8  Power Analyzer Results
      9. 3.3.9  Thermal Performance
      10. 3.3.10 Voltage Short Interrupt Test
      11. 3.3.11 Efficiency, iTHD, and Power Factor Results
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 Bill of Material (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

2.2.1.4 DC Voltage Balance Controller

A split capacitor is used for the output voltage bus in the Vienna rectifier. The voltages across these capacitors do not necessarily stay balanced naturally, hence a DC balance controller loop is added. This loop modulates an offset, which is added to the duty cycle thus, modulating the current through the midpoint to balance the voltages on the split capacitor.

A simple proportional gain is used for the DC bus balance controller, with the output of the balance loop given as in Equation 6.

Equation 6. G s _ o u t = V b u s _ P M - V b u s _ M N × G s _ g a i n _ K p