Even if the motor is not dual voltage, I think you would just need a VFD with a 415V output.

With the terminal box lid removed its usual to find a diagram of what is required to convert from Star to Delta, may be yours has a diagram ? If your motor has two rows of three terminals and one row is linked together using 3 brass links or pieces of wire, then it can easily be converted to 220 volts. The row with the links needs connecting using the links, top terminal to one below, all three along. I’ve sent you a PM.  John

If the motor is 415V and star connected, then when running each winding has 240V across it.  If the windings are re-connected in delta, which will be very easy if both ends of each winding are brought out to separate terminals as Duncan says, the motor will run at full power from a 220V VFD.  One thing to watch out for is that you keep the ends of each winding that are presently connected to the mains input connected in the same way.  The other end of the winding is then connected to one of the other mains inputs.  It is possible if you don’t keep a record of what’s connected where, to get one of the windings reversed, and then the motor won’t run properly.  If you get all correct but find the motor runs in reverse just swap two of the 3 phase input connections.

220V output VFDs are significantly cheaper than 415V as no step-up is needed from a normal 230V mains supply.

If you don’t have a lot of electrical experience get a new motor and drive package fron Newton Tesla.
If you are happy with electrics buy a decent quality VFD and a new motor.
See post https://www.model-engineer.co.uk/forums/topic/warco-gh1330-conversion-from-440v-to-240v/#post-842429 for an example of a similar installation.

For an older star connected motor it is more effective to get a new motor unless you really want to learn about motors and rebuild it.

Robert.

Have you taken off the terminal cover plate?  If 6 terminals are exposed then it can be connected in delta to run on 220V.  Duncan has a good point though I have an old 3ph motor on my mill that runs perfectly happily on a VFD.  But a Newton Tesla package can be recommended.

Have a look in the terminal box. As has already been said if it has six terminals then it can be swapped from star to delta. There are some motors with four terminals. There will be one wire on each of the three terminals and three on the fourth terminal. This type can be converted to delta by taking the three wires off the single (neutral) terminal and putting one wire onto each of the three terminals (just make sure that you do not fit the ends of the same winding onto the same terminal as the motor will just sit still).

If the motor has only three wires then it is permanent star connected. If you open up the motor and look inside there will be three wires connected together to form a star point. It should be possible (with some care) to split the star point apart and add another three wires, bringing them out into the terminal box and then configuring the six ends into a delta configuration.

Obviously any re-configuration of the winding connection has to be done with some care but it should be within the skill set of a careful amateur.

Martin