LAUSR

Abstract The lifetime of the wind power converter is strongly influenced by the thermal behaviour of the power devices and their mission profile. This paper focuses on the fundamental-frequency thermal cycles of the Impedance source inverter based wind power generation system. Impedance source inverters, e.g., quasi-Z source inverter, with two different modulation strategies have been explored to improve the reliability from reducing the power devices fundamental thermal cycles. A comparative evaluation of power losses, thermal performance, number of cycles to failure of the power devices in qZSI wind power system is performed for the two strategies. Such comparison can guide researchers to select a better modulation strategy to improve the lifetime of impedance source inverter so as to reduce the system cost and maintenance rate. The modulation effects on instantaneous power loss and thermal cycle in different wind speeds are evaluated. Simulations are carried out to validate the theoretical analysis and comparison.