Clarification on Maximum Voltage Limitation of EVLSTGAP3S6S Board

[Kranthi_Panuganti]

I am planning to purchase the EVLSTGAP3S6S evaluation board for my research. While reviewing the datasheet, I noticed that the board is specified to support a high-voltage rail of up to 520 V, limited by the MOSFETs and capacitors. However, I observed that:

• The board uses SCTH60N120G2-7 SiC MOSFETs, which are rated at 1200 V, 60 A.
• The film capacitor used (C4) is rated at 1.1 kV (Panasonic ECWFG1B335J).

Given that both components have voltage ratings above 1 kV, I would like to understand why the maximum voltage rail is limited to 520 V. I need to assess whether the board can support higher voltage operation (e.g., up to 800 V DC). Could anyone kindly clarify the reason for the 520 V limitation?

[AScha.3]

I can't tell you why the given voltage is 520, but I make inverter at work and so from my experience can say: you need a good safety margin for the switching devices, so 1200V is standard for use at 3 phase mains, 400 VAC.

We allow this also for use in USA, where the effective DC will be about 720 VDC, without problems. But still the nominal use is for 400 VAC.

Of course you have to adjust the switching and maybe the output inductor for the higher voltage, to get the same output power and not overload the inverter or the connected load. Then test it with the higher voltage and if all works fine, you can allow the higher mains with the tested settings and adapted load.

I think it's same here: the parts can work with higher voltage, but needs adapted parts and parameters and testing, to say: ok, working fine now at higher mains level.

[Kranthi_Panuganti]

Understood. Thanks a lot for your response.