Identification of a Dynamic Equivalent of an Active Distribution Network from Monte-Carlo Simulations

This paper deals with the derivation of a dynamic
equivalent of a distribution system for use in (phasor-mode)
dynamic simulations of large disturbances in the transmission
system. The original, unreduced system hosts inverter-based
generators such as photovoltaic units or full-converter wind
turbines. The individual behaviour of inverter-based generators
and loads is assumed to be reasonably well captured by a
parameterized model, but the values of its parameters are
uncertain. Monte-Carlo simulations involving random variations
of those parameters are performed, yielding a set of dynamic
responses to a given large disturbance. The equivalent is of the
”grey-box” type and its parameters are tuned in the least-square
sense to have its response falling in time-varying confidence
intervals obtained from the 5-th and the 95-th percentiles of
the distribution of dynamic responses. Simulations results are
reported on a variant of the CIGRE Medium-Voltage Distribution
Network Benchmark.