The rapid growth of renewable electricity generation introduces technical challenges that were previously uncommon. These include, for example, problems with exceeding the permissible voltage values in network nodes, overloading of transformers and line sections located behind the transformer, as well as balance problems. This article proposes an original methodology for eliminating these problems. Four objective functions reflecting different operator priorities were used. Attention is drawn to the increasing importance of the development of electricity storage. The results confirm that coordinated optimisation of voltage regulation, energy storage, and flexible load management enables increased renewable energy connection capacity while reducing power losses and improving the grid voltage profile. The case study results demonstrate the effectiveness of the proposed approach under the considered operating scenarios. The proposed tool can support network operators in managing MV grid operation under the considered scenarios. The ongoing energy transition requires network operators to react quickly to emerging problems. Therefore, advanced computational methods are needed to mitigate operational risks and respond to emerging constraints.

A study of the relative permittivity and electric strength of dielectrics printed by focus deposition modeling was presented. These electrical parameters determined the life-time reliability of devices made of dielectrics. Samples of PLA, ABS, PETG and ASA were tested according to IEC specifications. The dependence of the electrical properties of the samples on the type of material and printing precision was observed. Relative permittivity tests were carried out in the acoustic frequency band from 20 Hz to 20 kHz. It allowed analysis in a higher band than has been done in other publications to date. The electric strength of materials at 1.2/50 μs surge voltage was examined, which has not been widely analyzed before. Weibull plots, as a basis for determining the risk of failure, were prepared. The PETG FR (flame retardant) had the highest electric strength value, while PLA had the lowest. The differences with respect to tests at AC voltage were demonstrated. The printing technique affects the electrical strength value and location of potential electrical break-down.