Aiming at the increasing number of off-grid problems caused by low-voltage ride-through of distributed PV
this paper proposes a static clustering and equivalent modeling method of large-scale distributed PV in distribution networks for low-voltage ride-through scenarios. Firstly
we analyze the low-voltage ride-through switching characteristics of distributed PV
and put forward the low-penetration off-grid risk indices considering the electrical distance and installed capacity of each distributed PV; secondly
we take the low-penetration off-grid risk indices as the basis of clustering
and divide the distributed PV clusters based on the distance cost function and the -means clustering algorithm; lastly
according to the principle of aggregation of the distributed PV parameters
we adopt the REI lossless network equivalence and the Ward network equivalence to lossless the distribution network. and conduct simulation in PSASP for case comparison
the results show that: large-scale distributed PV static clustering and equivalent modeling method for distribution network oriented to the low-voltage ride-through scenario can significantly improve the transient simulation accuracy.
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