Polytechnic Institute of Lisbon

About: Polytechnic Institute of Lisbon is a education organization based out in Lisbon, Portugal. It is known for research contribution in the topics: Monetary policy & New Keynesian economics. The organization has 261 authors who have published 368 publications receiving 3569 citations. The organization is also known as: Polytechnical Institute of Lisbon.

A design approach to fdi/ftc of complex networked control systems

Abstract: The design of fault tolerant control (FTC) systems for large-scale complex networked control systems (NCS) is a difficult task due to the large number of sensors and actuators spatially distributed and networked connected. Despite the research effort on developing FTC systems most of these developments are designed globally leading to centralized FTC solutions inadequate to NCS. In this paper we present the first version of a toolbox based on multi-agent systems to design FTC systems for large-scale complex NCS. This toolbox is based on a decentralized FTC of NCS which relies on causal graph partitioning of the NCS digraph model and on intelligent distributed computing using multi-agents systems.

Bidirectional multilevel converter for electric vehicles

Abstract: In this paper is presented an H-Bridge Multilevel Converter topology for Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs). The topology of the presented multilevel converter allows the interface between the batteries, the electric motor of the vehicle, and the electrical power grid. Thereby, taking into account that the proposed multilevel converter requires the use of isolated voltage sources, the interface between the batteries and the multilevel converter is evaluated regarding the converter operation as a Battery Management System (BMS), controlling the charging and discharging processes. The interface between the multilevel converter and the electrical power grid is described considering a bidirectional operation. These modes of operation occur during the batteries charging process, denominated as Grid-to-Vehicle (G2V), and during the operation as Vehicle-to-Grid (V2G), that consists in delivering back to the electrical power grid a small amount of the energy stored in the batteries, in accordance with the electrical grid requirements and with the vehicle driver accordance. In both modes of operation, the waveform of the AC current of the electrical power grid is kept sinusoidal with unitary power factor, contributing to maintain a good level of power quality.

Residential PV systems with battery backup power attained already grid parity

Abstract: Due to the demise of FiT, PV grid connected systems focused towards self-consumption. A residential customer installing a grid-connected PV system, usually called a “prosumer”, is paid for the exported electricity less than 5 c€/kWh (or nothing) by the electricity provider while charged about 16/17c€/kWh for the same kWh. At this exchange rate it is more economical to consume than to export. Residential consumption does not coincide with PV production and the majority of the energy produced will be exported to the grid instead of self-consumed. NPV maximizes at a 95% of self-consumption in the best case studies which usually is attained with small percentage of self-sufficiency and low power installed. With further increase of retail electricity prices and decrease of PV costs the business case for storage becomes economically viable for residential customers with the advantage of increasing self-sufficiency and energy efficiency (energy is generated locally).