DQ-Frame Admittance Estimation of Three-Phase Converters with a Wide
Range of Operating Points
Abstract
The dq-frame admittance of closed-loop controlled three-phase
converters is a linearized model that is dependent on the operating
points of the system. Yet, it is impractical to measure the converter
admittance at all operating points. This paper, thus, proposes an
approach to estimating the dq-frame admittance of three-phase
converters at a wide range of operating points. The method applies
multidimensional interpolation to a given set of admittance data, which
is measured from the pre-defined operating points. The accuracy of
interpolation is then evaluated by using the posterior error estimation
method. The number of pre-defined operating points is next adjusted to
find a good compromise between the accuracy and efficiency of the
approach. Simulations and experimental results verify the effectiveness
of the approach.