The values posted above cannot be far from the real values.
Perhaps they use something like 700 A at 1400 V.
It is unlikely that they use a voltage over 1500 V, because the semiconductor switches used in the converter become much more expensive at higher voltages. A current of 700 A or even 1000 A can be easily handled by a single IGBT module. There are much bigger semiconductor switches that can handle several thousand ampere currents.
I should have been clearer, I did a web search and found other articles, which based on marketing information from the company, say it's 1000A and 1000V.
Perhaps they use something like 700 A at 1400 V.
It is unlikely that they use a voltage over 1500 V, because the semiconductor switches used in the converter become much more expensive at higher voltages. A current of 700 A or even 1000 A can be easily handled by a single IGBT module. There are much bigger semiconductor switches that can handle several thousand ampere currents.