Abstract
Photovoltaic (PV) powered DC motors driving dedicated loads (e.g. water pumps) are increasingly used in the remote rural areas of many developing countries. The key to their success is simplicity (direct coupling, no DC-AC inversion, no storage batteries, etc.). In this paper, a PV powered DC motor is used to drive an isolated three-phase self-excited induction generator (SEIG). It is found that due to the unique torque-speed characteristics of the SEIG, utilization efficiency is close to maximum at all insolation levels with no peak-power tracking. The proposed arrangement is useful as part of an integrated renewable energy system (IRES), which takes advantage of the inherent diversity of wind and insolation in most developing countries to improve power quality. The SEIG is driven by wind turbine, DC motor, or both. Performance of the system under different insolation conditions is analyzed.