The distributed nature and uncertainty of distributed photovoltaic(PV) systems pose new challenges to their equivalent modeling methods. In response to the existing issues of complex modeling and low accuracy in multi-machine equivalent modeling of distributed PV
this paper proposes an intelligent partitioning and equivalent modeling method for distributed PV clusters that integrates improved -means and CNN-LSTM. Firstly
multi-dimensional features including output voltage
output current
active power and reactive power at the point of interconnection
and outer-loop control parameters of inverters are selected as the basis for clustering. The optimal number of clusters for distributed PV clusters is determined by introducing the elbow method. A -means clustering algorithm that uses dynamic time warping distance to calculate the distance matrix and optimize the initial cluster centers is adopted to achieve intelligent partitioning of distributed PV clusters
effectively reducing the subjectivity and complexity of clustering. This paper combines the advantages of CNN and LSTM
where CNN is used to capture the spatial dimension features in distributed PV data
and LSTM focuses on extracting the dynamic characteristics of time series data
thereby constructing a CNN-LSTM equivalent model for distributed PV clusters that can reflect spatial distribution and accurately predict temporal evolution. Finally
the accuracy of the equivalent model of the clustering method and the distributed PV cluster equivalent model proposed in this paper is compared through simulation in PSCAD. The proposed model improves the equivalent accuracy of active power by 1.3
0.32
and 5.89 percentage points
and the equivalent accuracy of reactive power by 0.85
0.80
and 4.91 percentage points under three different disturbances
verifying the effectiveness and practicality of this method in improving the modeling efficiency and accuracy of distributed PV systems. This provides a technical reference for the analysis and optimization of large-scale distributed PV grid-connected systems.
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