TIDA-01606 11 kW Bidirectional Three-Phase T-type Inverter and PFC Demo Design

The TIDA-01606 10 kW AC/DC converter reference design with Texas Instruments and Würth Elektronik parts demonstrates how to implement a bidirectional three-level, three-phase, SiC-based active front end (AFE) inverter and PFC stage. The design uses a switching frequency of up to 90 kHz and an LCL output filter to reduce the size of the magnetics while maintaining a peak efficiency of 98.6%. Using these products, designers can easily implement a complete three-phase AFE control in the DQ domain. This bidirectional converter design enables both DC fast charging and vehicle-to-grid (V2G) power applications at up to 900 V.

The TIDA-01606 reference design features a range of Würth Elektronik passive components, including power inductors, ferrite beads, push-pull transformers, and more, supporting the design's capability as a three-level, three-phase SiC-based DC/AC grid-tie inverter stage. The incorporation of these Würth Elektronik parts contributes to the design's high efficiency (up to 99%), ability to handle high DC bus voltages (up to 1,000 V), and compact size due to a high switching frequency of 50 kHz.

To compensate for the voltage stresses generated by high-voltage DC chargers and solar arrays, updated topologies have been designed. Traditional half bridges block the full input voltage on each switching device. By adding additional switched blocking and conduction components, the overall stress on the device can be significantly reduced. This reference design shows how to implement a three-level converter. Higher-level converters are also possible, further increasing the voltage handling capability. Additional power density is also being enabled by moving to higher switching speeds of up to 90 kHz in the power converters. As this design shows, even a modestly higher switching speed reduces the overall size requirement of the output filter stage, a primary contributor to the design size. This reference design uses SiC MOSFETs alongside TI SiC gate driver technology to demonstrate the potential increase in power density. Despite the reduced footprint, a total harmonic distortion (THD) of less than 3% is achieved at maximum load.