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This paper presents an approach to model the transfer function of a four-conductor power-line cable for power-line communications. The model is derived from multiconductor transmission-line theory by taking into account all couplings between the conductors. The model allows one not only to determine the transfer function, but also the interference characteristics of that transmission medium. The transfer function for a straight line without branches is obtained first, and then crosstalk is derived. Finally, an N-branch network is simplified based on a generalization of the transmission matrix method. The transfer characteristics of the equivalent network are derived in a similar way as for a straight line.

Applying DSM for balancing renewable energy sources (RES), makes it possible to increase energy production of RES without the need for expensive (spinning) reserve on fossil power plants. The potential of DSM has already been demonstrated for peak shaving, but not for balancing RES. This paper illustrates the general and financial potential of DSM, describes the current practice and discusses some important aspects when using DSM for balancing. To conclude, the balancing potential of domestic freezers has been analyzed.

Power system states are not accurately known ahead of real time and are subject to natural variability, which leads to uncertainty in the system. Sources of uncertainty are amongst others load, renewable energy sources and contingencies. An aggregate measure for system's uncertainty is determined in order to have a single quantified value of the uncertainty level in the system. This allows to compare performance of power system reliability management according to various reliability criteria at different uncertainty levels in a transparent manner. A case study for a 5 node test system illustrates the use of the aggregate uncertainty measure and the impact of different uncertainty levels on short term reliability management of transmission system operators according to three reliability criteria. Results of the case study illustrate that probabilistic reliability management can lead to significant improvements in performance in terms of total system cost and curtailment of non-flexible load compared to reliability management based on deterministic N-0 and N-1 criteria, especially at high uncertainty levels in heavily loaded system conditions.

Transmission system operators apply selective load-shedding plans to prevent system wide interruptions and black-outs due to generation and transmission adequacy issues. If the load-shedding plan is activated, the electricity supply is intentionally switched off in indicated areas for a fixed period of time. The burden of load-shedding plans thus falls on a subset of consumers, while the benefits accrue to all consumers. This results in public opposition as illustrated with the publication of the load-shedding plan in Belgium in the winter of 2014 - 2015. To improve the social acceptability of load-shedding plans, we analyzed the unfairness of load-shedding plans based on Gini-based inequality indices and studied a top-down socialized compensation scheme and bottom-up priority service contracts to indirectly reduce the unfairness. The analysis is executed for a simplified version of the Belgian load-shedding plan for the winter of 2014 - 2015.

Electrical energy applications rely ever more on an information infrastructure (info'structure), consisting of heterogeneous off-the-shelf information and communication technology for hardware, software and networking. This provides flexibility for the application, but also implies vulnerabilities as the electrical energy infrastructure depends on the correct functioning of the info'structure, in spite of random (physical) and malicious faults. In order to provide a robust application behaviour for the energy application, the info'structure needs to be fault-tolerant and able to deal with a dynamic environment; middleware can provide the required graceful degradation in case of unrecovered failures, rather than resulting in a complete breakdown.