A topological reconfiguration procedure for maximising local consumption of renewable energy in (Italian) active distribution networks

Distribution networks (DNs) are facing great changes, due to the strong increase in distributed generation (DG), often driven by renewable energy sources. Designed to deliver electrical power from the transmission system to the final consumers, they are now becoming active and may inject power into the transmission network. In case of large DN, a portion of the system can be absorbing power from the transmission grid, while another portion injects power into it. In order to satisfy the power balance as much as possible at the local level, the distribution system operators are interested in the minimisation of the power exchange with the transmission network, maximising the local consumption of DG energy. This paper presents a topological reconfiguration procedure, based on the branch exchange technique, for the maximisation of the local consumption of renewable energy. A case study is presented, based on a real DN located in northern Italy

Energy harvesting from slow rotational motion

An electromechanical rotating energy harvester design is presented. The Energy Harvester is devoted to extract energy from a rotating flange in an agricultural machinery designed for ploughing and laying seeds. The harvested energy is used to supply a motion sensor that sends wireless signals to a console controlling the process. The device is structured as an axial electromechanical generator with excitation provided by permanent magnets. As no contact with stationary parts is allowed, an inertial reference is provided by a pendulum. Integrated design of electromechanical generator and pendulum is performed and results in terms of maximum harvested power are provided

Dual-PEEC Modeling of a Two-Port TEM Cell for VHF Applications

Two-port TEM cells with rectangular cross section are commonly used to produce plane electromagnetic waves with high electric field. The non-uniform structure makes the use of numerical methods extremely useful in the design phase in order to achieve a very good behavior of the TEM cell over a wide frequency range of operation. In this paper an extended version of PEEC is used to study a real device and results are compared with experimental ones

On forward and reverse coupling of vibrating piezoelectric energy harvesters

This document provides information about the analysis of effects coupling the mechanical and the electrical phenomena going on inside a piezoelectric energy har- vester. Two characteristics are exploited in energy harvesting: direct piezoelectric effect where stress is resulting by the application of an electric field and reverse effect showing an electric field resulting by stress application. Piezoelectric patches, bonded on beams free to vibrate under a mechanical stimulus, can be used as active elements. Point-wise material characteristics are described by symmetric matrices coupling together stress and electric field to the strain and the electric polarisation leading to reciprocal direct and reverse effects. Under operating conditions, the stress and electric field values applied to the material patch are not uniform and do not have the same spatial pattern resulting in a non reciprocal interaction. An explanation of this phenomenon is attempted by applying the Euler-Bernoulli beam theory model that allows the computation of two geometrical coefficients for direct and inverse interactions under uniform stress distribution. Com- parisons versus experiments carried out on a Macro Fiber Composite piezoelectric patch show that the model is able to estimate the effect

Understanding Reinforcement Learning Control in Cyber-Physical Energy Systems

The possibility of modeling a renewable energy system as a Cyber-Physical Energy System (CPES) offers new possibilities in terms of control. More precisely, this document discusses the applicability of Reinforcement Learning (RL) techniques to CPES. By considering a benchmark algorithm, we focus on conceptual and implementation details and on how such details relate to the problem of interest. In this case, we simulate how a RL model can optimize the energy storage control in order to reduce energy costs. The work also discusses the issues that arise in RL models and the possible approaches to these difficulties. Specifically, we propose investigating a better exploitation of the memory mechanism