Rotary phase conversion (RPC) is what people used for home shops before the flood of cheap Variable Frequency Drives (VFD) that make them no longer the go-to option of choice. RPC use an idler motor to generate a wild leg that must be balanced for the design load using capacitors and even then the wild leg won’t be exactly the same as line voltage on the other two legs, but likely close enough for regular motors.
VFD create a three phase power that is much closer to spec than an RPC and allows cool features like variable speed, reverse, soft start, electronic braking, etc. Older VFD often relied on three phase input but could be de-rated if fed with single phase only and still produce a three phase output.
Newer VFDs are often designed for single phase input and provide three phase without derating. I have a source for VFDs that are single phase input vector drives up to 15 hp output and are blue tooth capable, and optimized for wood workers and machine operators. For a room full of three phase machines a large RPC will be cheaper than a VFD per machine, but for a home user that may have a lathe, Drill Press, TS, mill, etc I would recommend a VFD solution for all of the cool features they provide. I have a 15 hp RPC and a half dozen VFDs in the shop.
