Stand-alone systems using renewable energy
sources, such as wind energy and photovoltaic (PV) energy with
storage battery banks are commonly used to supply remote
houses. Stand-alone hybrid wind-PV system with battery storage
is considered in this paper. It is proposed to employ squirrel-cage
induction generator (SCIG) in wind subsystem. Pulse-width
modulation (PWM) rectifier is used to control the SCIG. The
proposed control scheme employs the direct torque control (DTC)
strategy to modulate the ON / OFF durations of the switching
devices of the PWM rectifier to ensure maximum power
extraction through the SCIG operation. Furthermore, the control
scheme rids the proposed system from the need of dedicated
external capacitors for exciting the SCIG. Instead, the required
reactive power of the SCIG is provided by the switching of the
PWM rectifier. Simulation results are provided in the paper to
demonstrate the capabilities of the system.