Gheorghe Manolea

Informational decision support for risk reduction related to hailstorm in Oltenia region: Romania

This paper deals with the design of a system for decisional support dedicated to an anti-hail system. It is proposed a specific system for Romania anti-hail network, which completes the existing systems with specific information in order to identify the best solutions for both coordination and launch. The main topics refer to the system structure, information handled in the system and reconstruction of a signal based on Bayes criterion. The system comprises two main components: a subsystem of launch decision and a subsystem for assisting the launch decision. In order to achieve this system, the following important issues are considered: the use of communication via GPRS, monitoring the parameters throughout all operating period, log-values, status and alarms, operator actions logs, friendly graphical interface and the generation of tabular and graphical reports for any period. The system enables an increased efficiency by shortening the time for action, a good organization and a high degree of security.

Solutions for quality pre-control of crimp contacts used in electric power systems and electrical machines

Crimping is the most widely used method of pressure connection for permanent electrical contact between a wire conductor and a wire conductor terminating device. In this paper we present two solutions for connections quality pre-control of crimp contacts used in electric power systems and electrical machines and for early identification of the improperly executed connections, before final assembly. Thus can be avoid any damage that may occur during operation. The first solution supposes an experimental determination of specific losses by calculating the initial rate of temperature rise. This can be made drawing the tangent at the origin at heating curve. The method can be used to identify bad connections by passing a current through the winding at ambient temperature and simultaneously recording connections temperatures in the first few minutes since the current is setting. The second proposed solution is to apply to each element crimping an one level thermal indicator and making a test heating with a heating current corresponding to indicator critical temperature.

An improved control technique of a very precise positioning system used in hail suppression systems

A control strategy for positioning systems used in hail suppression is presented in this paper. The proposed position control solution is designed to obtain a precise control of the launch pad position over the azimuth and elevation, resulting in controlling a system with two degrees of freedom. The proposed strategy has been simulated starting from a permanent magnet synchronous motor that was modeled by means of an inversed magnetic model. The control algorithm initially takes into consideration a regulation of the main motors electrical quantities: torque, speed and position. Then a mechanical model for the system was developed, accounting for the experimentally determined static torque, total reduction factor (worm gear and launch pad), total inertia and efficiency. The simulation work has been developed in Matlab Simulink, and it considers two different systems, each one formed by one motor, along with its worm gear and the corresponding mechanical parts. The simulation results are provided for both positioning systems, for the azimuth and elevation. The obtained results demonstrate that the proposed control solution is able to meet the application requirements and can be implemented with a real-time processor.

Control of the electric drive of the anti-hail launching system

In the present, the Romanian anti-hail launchers are manually operated. This means that the positioning of the launcher on the two directions (azimuth and elevation) are adjusted based on the commands, by the human operator. The paper describes the implementation and experimental results of the electric drives of the two axes by using permanent magnets synchronous motors (PMSM) supplied by smart drives. The solution offers the possibility of automation and integration of the anti-hail launchers within intelligent systems.

Current distribution in crimped connections

In the paper, the direct current distribution in the rectangular cross-section strands of stranded conductor, in the case of crimped connection of two identical stranded conductors is studied. The influence of relative contact resistance and of the number of strands in conductor is analyzed. Two configurations are considered: interleaved and superposed strands. The contact resistances between adjacent strands are considered equal to each other.

The hardware structure of the monitoring system for the Romanian anti-hail rockets launch units

A national anti-hail system was established in Romania in 1999, and recently was established a National Authority. Presently, in Romania an anti-hail system is functioning, and it is desired to implement a large scale National Anti-hail System. This paper deals with the design of a monitoring system for an anti-hail system. It is proposed a specific system for Romania anti-hail network, which completes the existing systems with specific information in order to identify the best solutions for both coordination and launch. The main topics refer to the overview of system, the main blocks of the Master and Slave modules, the experimental results regarding functioning of the system are fully discussed. Finally, some conclusions are collected in section 5. In order to achieve this system, the following important issues are considered: the use of communication via GPRS, monitoring the parameters throughout all operating period, log-values, status and alarms, operator actions logs, friendly graphical interface and the generation of tabular and graphical reports for any period. The interface of the monitoring system is underlined in section 2 where are presented the main functions of the command buttons. The system enables: an increased efficiency by shortening the time for action, a good organization and a high degree of security.

Contributions to the development of the Romanian anti-hail system

The method used in Romania for combating hail is the sowing of the clouds method, with missiles launched from the ground. This paper presents contributions of the University of Craiova, Center for Innovation and Technology Transfer in the development Hail Suppression System.

Access system for vehicles powered by photovoltaic panels

To access the vehicles in different areas are frequently used automatic barriers. This paper presents such an access system, achieved a small scale that uses photovoltaic panels as main energy source.

Design of a virtual intrument in LabVIEW for crimped connection temperature measurement

This paper proposes a solution for crimped connection temperature measurement using data acquisition system NI PCI 6221, LabVIEW and thermocouple. The solution offers a modern alternative to traditional temperature measurement systems: a flexible virtual instrument with the advantages of changing the functionality by the users according to their needs. Virtual instrument was design in LabVIEW and enable user the possibility to measure temperature of crimped connection and display in real time on graphical form, save measured values and select one up to 8 physical channels. Finally, experimental determinations were made in order to verify the functionality of the equipment and different possible situations in which the solution can be used were outlined.

Technological solution for increasing the quality of crimped connections

In this paper we propose a new technological solution for crimping, to increase the quality of crimped connections by reducing the contact resistance and increasing the connection reliability. The method use two adjacent crimp indents in opposite sides. To evaluate the quality of crimped connections we make experimental determinations of contact resistance corresponding to two crimp method: the first method uses one crimp indents and the second is a proposed method with two crimp indents. All the used samples are with 8 copper wires 7.1 × 3 mm2. After we measure the contact resistance, we compare the obtained values for the two crimp method and present the conclusions.