MICROPROCESSOR CONTROLLED COMMU- TATORLESS DC SERIES MOTOR

Abstract

The dissertation concerns the design, fabrication and performance of the microprocessor controlled commutatorless d.c, series motor by using induced voltage commutated inverter along with induced voltage sensor. The firing pulses for thyristors of the inverter are generated by the microprocessor in proper sequence with the help of synchronizing signal derived from the terminal voltages of the synchronous machine. A three= phase. synchronous motor supplied by a line commutated inverter (LCI) with the excitation winding connected in -series to the d.c. link becomes equivalent to a simple,commutatorless d.c. series - motor which gives excellent d.c. series motor characteristics. The steady state analytical model of the drive is deve-loped by using steady state equivalent circuit and performance is .computed therefrom. , The performance is obtained experimen-tally also using the fabricated system and ' the experimental- results have shown a good correlation with the computed results. The configuration of the firing angle control scheme -used in present work is comparatively simple and requires less software and hardware in comparison to the earlier schemes.