Simulation software can be used not only for checking the correctness of a particular design but also for finding rules which could be used

in majority of future designs. In the present work the recommendations for optimal distance between a side feeder and a casting wall were

formulated. The shrinkage problems with application of side feeders may arise from overheating of the moulding sand layer between

casting wall and the feeder in case the neck is too short as well as formation of a hot spot at the junction of the neck and the casting. A

large number of simulations using commercial software were carried out, in which the main independent variables were: the feeder’s neck

length, type and geometry of the feeder, as well as geometry and material of the casting. It was found that the shrinkage defects do not

appear for tubular castings, whereas for flat walled castings the neck length and the feeders’ geometry are important parameters to be set

properly in order to avoid the shrinkage defects. The rules for optimal lengths were found using the Rough Sets Theory approach,

separately for traditional and exothermic feeders.

Afeeder automation (FA) system is usually used by electricity utilities to improve power supply reliability. The FA system was realized by the coordinated control of feeder terminal units (FTUs) in the electrical power distribution network. Existing FA testing technologies can only test basic functions of FTUs, while the coordinated control function among several FTUs during the self-healing process cannot be tested and evaluated. In this paper, a novel cloud-based digital-physical testing method is proposed and discussed for coordinated control capacity test of the FTUs in the distribution network. The coordinated control principle of the FTUs in the local-reclosing FA system is introduced firstly and then, the scheme of the proposed cloud-based digital-physical FA testing method is proposed and discussed. The theoretical action sequences of the FTUs consisting of the FTU under test and the FTUs installed in the same feeder are analyzed and illustrated. The theoretical action sequences are compared with the test results obtained by the realized cloud-based simulation platform and the digital-physical hybrid communication interaction. The coordinated control capacity of the FTUs can be evaluated by the comparative result. Experimental verification shows that the FA function can be tested efficiently and accurately based on our proposed method in the power distribution system inspection.

Feeder reconfiguration (FR), capacitor placement and sizing (CPS) are the two renowned methods widely applied by the researchers for loss minimization with node voltage enrichment in the electrical distribution network (EDN), which has an immense impact on economic savings. In recent years, optimization of FR and CPS together can proficiently yield better power loss minimization and save costs compared to the individual optimization of FR and CPS. This work proposes an application of an improved salp swarm optimization technique based on weight factor (ISSOT-WF) to solve the cost-based objective function using CPS with and without FR for five different cases and three load levels, subject to satisfying operating constraints. In addition, to ascertain the impact of real power injection on additional power loss reduction, this work considers the integration of dispersed generation units at three optimal locations in capacitive compensated optimal EDN. The effectiveness of ISSOT-WF has been demonstrated on the standard PG&E-69 bus system and the outcomes of the 69-bus test case have been validated by comparing with other competing algorithms. Using FR and CPS at three optimal nodes and due to power loss reduction, cost-saving reached up to a maximum of 71%, and a maximum APLR of 26% was achieved after the installation of DGs at three optimal locations with the significant improvement in the bus voltage profile.