TIDA-00915: Bi-directional controlled rectifier

Dear Sam,

Many thanks for your patience. Please find the answers below:

1. This is a 3-phase inverter. Thus it works in 4 quadrants. Naturally we can use it as a rectifier. Correct?

 In principle yes.

2. If we use it as a rectifier and we measure output DC volt and current and use feedback loop, theoretically we should be able control output DC volt and power factor. Correct? If not why?

 There is no DC voltage measurement implemented. It was there for its previous version but we had removed it for the current version we promote on ti.com. I thought I just mention this in case you would be looking at an older version of the documentation. There is also no LCL-filter on the AC-side. You would need to add this and also add current and voltage sensing on the line-side of that filter.

3. If we use it as a rectifier, and assuming 240VAC input, will we be able to control the output DC voltage down to 48VDC?

 The 3-phase active rectifier can do power factor correction in boost mode only. So, the output DC voltage will be greater than 240* = 340V. So to get 48V DC, another power conversion stage is required to step down from output of rectifier to 48VDC.

4. If we use it as a rectifier will we be able to control power factor?

Yes, if current and voltage sensing is provided on the line-side prior to the LCL-filter.

5. The reference design states that peak power is ~2KW & continuous power is 1.25KW. Do we know the maximum duty cycle or peak power period?

The 2KW is calculated from the max current rating of the GaN MOSFETs in TIDA-00915. We did not take real measurements to determine the max power capabilities over time. The 1.25KW were measured for continuous load until temperatures had settled (>30min) at 25C and extrapolated to 50C.

Best regards,

Michael