Search results for " Control"

Overview and experimental analysis of MC SPWM techniques for single-phase five level cascaded H-bridge FPGA controller-based

2016

This paper presents an overview and experimental analysis of the MC SPWM techniques for single-phase cascaded H-bridge inverter. The multilevel power converters are an alternative to traditional converters known as “three-level converters”. The voltage waveforms and the related frequency spectra, which have been obtained by simulation analysis in Matlab-Simulink environment, are here reported for all the proposed modulation techniques. The simulation results have been experimentally validated through means of a DC/AC, five-level, single-phase converter prototype with an appropriate test bench.

Computer Simulation for the Study of CNC Feed Drives Dynamic Behavior and Accuracy

2007

In the application of CNC feed drives it is desirable to predict the servo performance. By using computer simulation techniques it is possible to construct an accurate model of the servo drive. This simulation procedure makes it possible to anticipate machine design problems and correct them. This paper deals with a model of a feed drive, which consists of a motion control system driven by a DC motor. Both position and velocity feedback loops are present in the structure of the system. By means of MATLAB & Simulink software, simulation diagrams were built in order to test the behaviour of the system. Experimental data are also presented in order to confirm the accuracy of the theoretical mo…

Towards a SDN-based architecture for analyzing network traffic in cloud computing infrastructures

2015

Currently, network traffic monitoring tools do not fit well in the monitoring of cloud computing infrastructures. These tools are not integrated with the control plane of the cloud computing stack. This lack of integration causes a deficiency in the handling of the re-usage of IP addresses along virtual machines, a lack of adaption and reaction on highly frequent topology changes, and a lack of accuracy in the metrics gathered for the networking traffic flowing along the cloud infrastructure. The main contribution of this paper is to provide a novel SDN-based architecture to carry out the monitoring of network traffic in cloud infrastructures. The architecture in based on the integration be…

Review of web-based information security threats in smart grid

2017

The penetration of digital devices in Smart Grid has created a big security issue. OWASP is an online community of security professionals that identifies the most critical web application security risk in IT domain. Smart Grid also uses client-server based web-applications to collect and disseminate information. Therefore, Smart Grid network is analogous to IT network and similar kind of risk exists in the Smart Grid. This paper review the security risk in Smart Grid domain with reference to OWASP study. The Smart Grid security is more biased towards vulnerabilities associated with a machine to machine communication. Methodology to minimise the risk of attack is also discussed in this resea…

Joint routing and per-flow fairness in wireless multihop networks

2008

In wireless multihop networks communication between two end-nodes is carried out by hopping over multiple short wireless links. Traditional CSMA/CA based media access control does not work satisfactory in a multihop scenario, since an intended target of a communication may be subject to mutual interference imposed by concurrent transmissions from nodes which cannot directly sense each other, causing unfair throughput allocation. Although TDMA seems to be a more promising solution, careful transmission scheduling is needed in order to achieve error-free communication and fairness. In our previous work, a TDMA scheduling algorithm has been proposed that schedules the transmissions in a fair m…

Evolutionary approach to coverage testing of IEC 61499 function block applications

2015

The paper addresses the problem of coverage testing of industrial automation software represented in the IEC 61499 standard, one of the recent standards for distributed control system design. Contrary to model-based testing (MBT), the paper focuses on implementation coverage, not model coverage. An approach based on evolutionary algorithms is presented which generates coverage test suites for both basic and composite IEC 61499 function blocks. It employs two third-party tools, FBDK and EvoSuite. The evaluation of the approach was performed on a set of control applications for two lab-scale demonstration plants. Results show that the approach is applicable and shows good performance at least…

Towards Risk-aware Access Control Framework for Healthcare Information Sharing

2018

A PLC based monitoring and remote control architecture for Distributed Generation and Storage systems in LV smart grids

2021

(Abstract) This paper proposes a new power line communication (PLC) architecture for monitoring and remote control of Distributed Generators (DG) and Energy Storage Systems (ESS) connected to low voltage distribution networks. The final aim is to improve the performance of the PLC link in terms of robustness and efficiency in devices addressing. The proposed solution is based on a concentrator, to be installed in secondary substation, and a new PLC bridge, to be linked both to inverters and interface protection systems of DGs or ESSs. In this way, a communication link is obtained between distribution system operator (DSO) and DG or ESS owners. The proposed system is able to provide advanced…

Security, Reliability and Usability of mHealth Environments

2015

Mobile technologies confer mobility and autonomy on patients with the advantage of access to home care and health care services on demand. However, these benefits impose challenges to the future health care services. For instance, computation capacity of a conventional smartphone provides applications and services with sufficient power of calculation and automation to assist in daily life activities and medical purposes. Combined with a user-friendly interface, mobile technologies can be an easy and efficient manner to help people who are in a condition of cognitive deterioration or have a chronic disease which demands a close connection to near family members and/or to health care services.

Implementation and Experimental Tests of a Management System for MV/LV Distribution Grids

2019

The continuous monitoring of network power flows and the remote control of Distributed Generators and Energy Storage Systems are the essential elements to allow a full exploitation of Renewable Energy Sources and their real integration in distribution networks. Thus in the paper a management system is presented for load flow monitoring in MV/LV distribution network. Moreover, on the basis of calculated power flows, the management system is able to send control commands to DGs and ESSs, to vary their power production or power factor or eventually to disconnect them in order to maintain the network stability. The proposed solution was really implemented in the MV network of Ustica Island, dev…