Stability analysis of a current source rectifier based drive for aerospace applications

This paper presents a theoretical analysis of the criteria which govern the stability of a current source rectifier drive, for a switched reluctance machine or actuator. A small signal stability analytical model, employing a state-space averaging technique, is established and verified by a comparison with a timedomain numerical simulation study. In order to fulfil the power quality requirements of the ac bus, a passive input filter is employed in the drive, which together with the supply impedance may result in unstable operation, since a power electronic converter behaving as a constant power load exhibits negative incremental input impedance. Given the array of valid filter parameters, a seemingly well designed input filter which satisfies the power quality requirements, can often cause significant performance and control degradation when installed in to a closed-loop controlled switching converter.