Design and Performance Evaluation of a Battery-Assisted Fuel-Less Generator Using a Permanent Magnet Synchronous Generator with Automated Feedback Control

The energy insufficiency experienced in Nigeria is estimated to affect upwards of 85 million people, thus leading todependence on fuel-based generators. As such, environmental as well as socio-economic consequences are inevitable.This paper describes the process of designing, fabricating, and analyzing a closed-loop battery-assisted generator systemthat is fuel-free. The components used for the fabrication included a 12 V / 75 Ah battery bank, a 3 HP (2,237 W) DCmotor, and a three-phase PMSG of 10 kW. Also, a 6:1 belt and pulley speed ratio was employed to link the motor to thegenerator. The system was controlled using an auto-relay feedback loop which constantly monitored the voltage atterminals and redirected some of the generated current through a full bridge rectifier to recharge the battery. Thisarrangement extended the operational autonomy of the system without external intervention. Equations to determine theelectromagnetic flux linkage, mechanical power, pulley kinematics, system efficiency, and battery state-of-charge wereobtained and verified experimentally. Without any load, the prototype provided a constant voltage output of 220 V, 50Hz. During step load test from 35 W to 300 W, the maximum efficiency obtained was 74.88% at 100 W. When thefeedback loop was activated at 300 W, the system operated for 960 seconds compared to 360 seconds (2.67 times). Astatistical analysis of replicated experiments showed a mean efficiency of 74.88 ± 1.83 % at 100 W (95% CI: 70.26 to73.82%) using second order polynomial model.