No abstract

This paper presents a co-simulation model using MATLAB ® toolboxes to illustrate an interaction between the communication system and the energy grid, coherent with the concept of smart grid that employs IEC 61850 communication standard. The MMS (Manufacturing Message Specification) protocol supported by IEC 61850, based on TCP/IP, is used for the vertical communication between the Supervisory and Data Acquisition (SCADA) system and Intelligent Electronic Devices (IEDs) embedding the local control of different parts of the smart grid. In this paper an IED supporting the power control of a photovoltaic (PV) plant connected to a low-voltage (LV) utility grid is considered. Communication system consisting of the transport layer and a router placed on the network layer is modeled as an event-driven system using SimEvents ® toolbox and energy grid is modeled as a time-driven system using SimPowerSystems ® toolbox. Co-simulation results are obtained by combining different communication scenarios and time-varying irradiance scenarios for the PV plant when this one is required to provide a certain power in response to a power reference received from SCADA over the communication network. The analysis aims at illustrating the impact that stochastic behavior and delays due to network communication have on the global system behavior.

Integration of various equipments into a distributed automation project becomes a necessity for building large automation systems and rises problems of networking of heterogeneous nodes in a complex communication network. In this paper, we investigate the interconnection problems of nodes into an industrial network using Modbus protocol, and propose solutions to address the problems optimally.

The paper deals with the structure and the properties of a system implementing the remote laboratory, m the technical area, for university purposes. This system was intended for remote experiments on physical objects, but it allows virtual experimentation, too. The main contribution is the original software written for this laboratory, created by the authors and tested in the university. The key feature of the laboratory is that it allows the remote student to take full control of the equipment, in order to solve the didactical subject, protecting in the same time the laboratory against possible attacks. The described application is in the field of automatic control, hut remote experimentation in the field of electronics or other technical subjects is also possible. The student is allowed to collect data from the equipment, to reconfigure on-line the structure of the equipment and to write his own automatic control algorithm, without being limited to predefined algorithms. 0-7803-7596-3/02/$17.00 02002 IEEE

The paper presents a biomimetic sonar head with four degrees of freedom. The biomimetism is at the level of functions and structures, i.e. one emitter (mouth) and two receivers (ears). It focuses on simplicity and compactness to assure reliability and portability of the sonar head on various mobile objects. It includes the electronic circuits for control and signal processing. The reliability is assured by using the latest available digital servomotors and ultrasonic transducers. The portability is obtained by putting all electronic circuits in a single box connected only by USB communication port to an ordinary computer (PC). The sonar head is designed for mobile objects (e.g. autonomous vehicles, robots). The present paper presents the approach with fixed frequency (~ 45 kHz) and piezoceramic ultrasonic transducers. The first part presents the kinematics chain assured by the mechanical structures and the electric and electronic circuits of the sonar head. A detailed analysis to drive the basic relations for elevation and azimuth and the upper and lower working limits are considered also.