SLVAG13 April   2025

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2DC vs. AC Power Grids: A Comparative Overview
  6. 3DC Microgrids Across Industries
  7. 4TI Solutions for DC Applications
    1. 4.1 10kW GaN-Based Single-Phase String Inverter with Battery Energy Storage System
    2. 4.2 Bidirectional, Dual Active Bridge Reference Design for Level 3 Electric Vehicle Charging Stations
    3. 4.3 11-kW, Bidirectional Three-Phase Three-Level (T-Type) Inverter and PFC Reference Design
    4. 4.4 300V-1,000V Input 48W Isolated Auxiliary Power Reference Design with Low Standby Power
    5. 4.5 AFE for Insulation Monitoring in High-Voltage EV Charging and Solar Energy Reference Design
  8. 5Conclusion
  9. 6Reference

4.3 11-kW, Bidirectional Three-Phase Three-Level (T-Type) Inverter and PFC Reference Design

Connecting the DC microgrid to the AC grid requires a bidirectional power supply. This supply handles AC-to-DC conversion with a high power factor and must be able to perform DC-to-AC conversion as an inverter. Because of the power levels, efficiency as well as thermal management are of top concern.

TI’s bidirectional three-phase reference design, shown in Figure 4-3 and Figure 4-4, has a 11kW bidirectional inverter and PFC stage that can handle 600V to 900V on the DC bus, as well as three-phase 400VAC from the grid.

Bidirectional Three-Phase Reference Design Board Photo and Block DiagramFigure 4-3 Bidirectional Three-Phase Reference Design Board Photo and Block Diagram
Bidirectional Three-Phase Reference Design Block DiagramFigure 4-4 Bidirectional Three-Phase Reference Design Block Diagram

The full reference design consists of two separate boards. The main board has all the switching devices, an LCL (inductor-capacitor-inductor) filter, sensing electronics and power structures. The second board hosts the control circuitry, based on a C2000™ digital signal processor control card. The complete design achieves a peak efficiency of 98.6% and has a power density of 2.2kW/L.