I've noticed several threads recently where turning on VFD units has tripped the supply RCD. I too have had similar problems since first installing a VFD some years ago, recently this has seemed to become more of a problem.

I've just realised that since I replaced on old floodlamp fitting on the outside of the garage a few weeks ago, the problem has vanished. Now even my largest VFD doesn't trip the RCD when turned on.

I don't know if the issue was that the floodlamp was an open face type, or that the weather had got into the PIR motion detector housing.

Anyway – the learning (as I recall some have commented in other threads) is don't rush to blame either the VFD or the RCD, carefully check anything else fed from the same supply before buying a replacement RCD with different characteristic. In my case simply isolating the exterior lights at the MCB would likely have pointed to the cause a long time ago.