Don't need a inverter and a rectifier both. An inverter normally takes DC 12 or 24 volt and turns it into AC 110 (so it rectifies and steps up all in one). If your 3 phase motor is putting out say 24 volts VAC at 20 amps at 3000 rpm (480 watts) then you only need to rectify it to DC and run a 24 volt system (look for something with a 95% effencience for this they have it). Not that pricey either) If your 3 phase motor is putting put 110 VAC at 20 amps at that same 3000 rpm (2200 watts) and you want to charge a 24 volt battery then you would need to rectify and step down the voltage (and raise the amps). Pricier but not by much. Now if you need to go from 24 volts dc to say 110 volt AC THEN you need an inverter and are losing 15% because the efficiency is usually only 85% on inverters!!!. And pricey unless you get a cheap on that fries easily. I replaced 3 inverters in 8 years but the charge cpntroller nevwr jad to be replaced. It is better to start with more voltage than you need and step down you have less loss of energy in the transfer compared to stepping up the voltage. The price of all these charge controllers for solar have dropped alot in the 10 years I have lived off-grid. My 12/24 volt 20 amp charge controller cost me $80 back then now you can get one from 10 to 20 dollars.