A PV array is a nonlinear d.c. source and its operation has to be care
fully matched to that of its equivalent electrical load in order to ex
tract the maximum available energy. Two PV pumping schemes are investi
gated to get the maximum gross mechanical power. The system based on t
he separately-excited d.c. motor is matched through the control of the
motor excitation, while for the system based on the induction motor,
the voltage source inverter frequency is controlled by maximum mechani
cal power operation. Copyright (C) 1996 Elsevier Science Ltd.