  This paper proposes a novel integrated multiport bidirectional back-to-back
power converter for a type-4 wind turbine that accommodates a battery and
supercapacitor for energy storage. The circuit topology reduces 4 switches
compared to the traditional configuration. Moreover, owing to the dual-buck
structure embedded in the phase leg, the circuitry has no short-circuit path,
therefore it withstands short-circuited events for a much longer time than the
normal phase-leg and prevents the reverse current in turn-off recovery. The use
of a hybrid energy storage system with battery and supercapacitor helps smooth
out the power output under wind gusts and stabilizes the DC-link voltage under
grid fault conditions. The case studies are carried out with a 1.5 MW wind
turbine system. Simulation results are provided for the theoretical validation.
