dc drive

I am using three phase dc drive in put 380 v

final out put ( measured on dmm) when it works vary from 20 VDC to 215 VDC

full bridge is used .

final motor is dc motor. and max RPM is about 3000 RPM. but when i connect same motor on single phase ( full bridge) controller its speed is too higher than expcted. as it run for required 3000 RPM only on 28 - 32 VDC ( 6 Amp). And now its not carring load in my application.