A Non-isolated Modified Zeta Converter-fed DC Motor under Load Condition

HIGHLIGHTS

• Use of boost power stage ensures improved voltage gain for the existing Zeta converter.

• The proposed Zeta topology produces high voltage gain at low duty ratio itself.

• Low voltage stress is observed on both power switches.

• Characteristics of the DC motor-generator set are obtained by duty ratio adjustment.

Abstract

In this paper, the steady state performance characteristics of a separately excited DC motor fed by a non-isolated positive output DC-DC converter of high voltage gain Zeta topology are presented. The suggested Zeta converter configuration energized by a DC source is operated in continuous inductor current mode. The DC motor is mechanically coupled with a DC generator. The armature voltage and hence the speed of the motor is controlled by varying the duty ratio (k) of the converter for the given converter input voltage and generator-side load resistance. The proposed DC motor speed control scheme is simulated in MATLAB/SIMULINK platform for performance validation. The various performance measures such as torque, speed, armature current, armature voltage, load current, and efficiency for the motor-generator set are explored. The comparison of voltage gain of existing Zeta topologies and the voltage stress calculation are also illustrated.

Keywords:
Continuous inductor current mode; DC motor-generator set; Duty ratio; MATLAB/SIMULINK; Performance characteristics; Zeta topology