Modeling and identification of load nodes with nonlinear current-voltage characteristics based on measurement data

The relevance of the research consists in improving the methods of modeling non-sinusoidal and asymmetric modes of complex electrical networks. The modes of complex electrical networks are calculated taking into account the distribution of the parameters of transmission lines, geometry of wire suspension, nonlinear properties of node loads. This significantly complicates the task, but at the same time provides new, more accurate information on the modes, in particular, the determination of contribution of this or that non-linear load to formation of voltage quality indicators and additional losses of electricity from current unsinusoidality. The existing variety of methods and approaches to modeling loads, reflected in the article, points to the relevance of the issue and significant scientific interest in their development. The main aim is to develop a new approach to simulation of nonlinear loads. The methods of the research. The time diagrams of voltage and current, obtained by instrumental examination, are used as the initial data to identify the industrial load node. The time diagrams of voltage and current of a six-pulse converter were obtained from the known analytical relationships. The authors have used the well-known approach to modeling nonlinear systems when developing the model and identification algorithm. The data of load measurements were obtained by the Regional center of resource saving TPU during the instrumental survey. The results. The authors proposed the functional load model with nonlinear volt-ampere characteristics and necessary design relationships, providing mathematical modeling in steady-state modes, and the algorithm for identifying nonlinear loads. The paper introduces the results of load identification in the form of a six-pulse converter and the load of a common industrial node of the 110 kV network as an example.