Power supply regulator 38V

A friend of me one person study about CNC , but stick the problem about power supply of 38V servo motor. Then beg me help to seek power supply regulator 38V Circuit , please. If there is many the circuit or get choose that best. This circuit is one in the choice. It uses Transistor be main part. Follow the circuit Q1 use the number BD139 or the other. For Q2 use 2N3055 highly popular numbers . And Zener Diode use 37V-40V power rate about 1A. The Transformer use 2A sizes. The BD1 use 4A - 6A 200V. Detail other sizes please see in the circuit. I hopes this circuit may in rows think in applying work other , please sir.

Power Supply   Switching Power Supply   DC to DC Converter   Inverter
Battery charger   Led flasher   Motor speed controller   LM317   IC 741
RF radiofrequency   Electronic control   Digital Circuit   Alarm home system
DC to DC converter step up voltage   Mini project   Temperature control
FM receiver   Dual power supply   Fluorescent lamp   Pic microcontroller
Led display   RF amplifier   FM transmitter   LM324   LM723   TL494
2N3055   LM338   SG3525   Li-ion battery charger   Pulse generator