Samuel Galceran

Development and implementation of a condition monitoring system in a substation

Maintenance is a key activity for utilities in order to assure the proper operation of their networks. And it implies a huge amount of human and economic resources. Saving maintenance costs means that it is needed to invest in innovation. In order to improve the effectiveness of the maintenance in the electrical utilities, a transformation from preventive maintenance based on time (TBM) to preventive maintenance based on condition (CBM) is taking place. The core element of the CBM strategy is the implementation of a condition monitoring system. This work treat about the development and implementation of a condition monitoring system in a pilot plant of an electric utility consisting in a 66/25 kV, 30 MVA power transformer and 66 kV and 25 kV circuit breakers. The system was implemented by using the monitoring functions of commercial protection relays equipped with IEC61850 communication capabilities. In this work, first a description of the monitoring system is presented, followed by the description of the pilot plant where the system has been installed and finally, the conclusions and further works are presented.

Sensorless control of PM synchronous motors and brushless DC motors - an overview and evaluation

This paper provides a review of the literature addressing sensorless operation methods of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, those methods based on back emf measurements, and those methods based on novel techniques not included in the previous categories. The paper concludes with a comparison table including all main features for all control strategies

Probabilistic assessment of wind power production on voltage profile in distribution networks

Distribution power networks are accommodating more and more generation and most of them are based on renewable sources, like wind power. Then, this new generation, generally known as distributed generation (DG), has a stochastic power production that affects technically the network in different ways. However, availability and power quality must be kept within standard limits. Deterministic approach can not cope with this issue and a probabilistic assessment is needed. Wind power has a high level of integration around the world. Then, its impact of voltage profile in a distribution network is analyzed.

A laboratory test bed for PM brushless motor control

There has been tremendous growth in the use of modern digital signal processors (DSP) in control and other applications in the past few years. While courses offered in the electrical and computer engineering disciplines cover such topics as mobile and digital communications, image and sound encoding and decoding, few courses focus on the use of DSP in real-time control of electrical machinery. On the other hand, there is a growing need in industry for engineers who can perform control design and system integration for various applications in motor control. This paper describes a laboratory test bed for PM motor control for a new course on control of electrical machinery offered at School of Industrial Engineering of Barcelona ETSEIB, Polytechnic University of Catalonia, Barcelona, Spain. An outline of the course structure, laboratory setup, and the design aspects for implementing modern real-time motor control applications are presented

Low cost sensorless control of permanent magnet motors - an overview and evaluation

This paper provides a review of the literature addressing sensorless operation of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, and algebraic manipulations of machine equations, those methods based on back emf measurements, and those methods based on novel techniques not included in the previous categories. A review of machine model equations is also treated. The paper concludes with a comparison table including all main features for all control strategies

Industrial processes susceptibility in relation to their environment

The perfection of sine wave power supply is always assumed, that is to say, voltage power supply has 50 or 60 Hz perfect sinusoidal waveform and its root mean square value is the rated one. It is known that electrical companies cannot supply this perfect kind of waveform, though in normal conditions they are within the limits imposed by regulations. Disturbances are generated under abnormal conditions such as lightning on a power system or the opening of a switch. These disturbances can affect electronic equipment. The equipment that requires a constant voltage is particularly affected. In this paper, the results of several tests accomplished are shown. The tests were carried out with linear power supplies, personal computers and programmable logic controllers (the last ones have switched power supplies) by means of the voltage sags generator designed by the Electrical Engineering Department of UPC. The latest technologies used in inverters of adjustable speed drives (IGBT for half power) have considerably increased bearing damage and dielectrics breakdown in induction motors due to use conditions of these converters. This fact has contributed to increasing the research to establish solid theories which explain these phenomena and help to find solutions for them. Problems related to voltage feeder disturbances also remain unsolved. This aspect is becoming more and more important for the users, since it is the main cause of interruption in multiple industrial processes. The aim of this study is to establish theoretical and experimental bases that help to understand and solve those problems arising in industrial applications, and also to provide users with useful tools for the correct operation and maintenance of the installation.

Comparative Experiences in Remote Automation Laboratories with Real Plants

In recent years, there has been a significant increase in remote learning courses. In some disciplines, including PLC (Programmable Logic Controller) automation, doing laboratory practice ‘at home’ with all the required material is difficult. In these cases, the possibility of doing laboratory practice remotely is of especial interest. We can use simulators to make an applet that simulates a PLC, but we discarded this because the students saw the practices as very artificial and unrealistic and hence their motivation decreased. In this paper, we describe how we have tried several possibilities of remote PLC programming and how their advantages and drawbacks have been analysed.

Use of IEC1131 programming in virtual laboratory

Virtual laboratories are being used in automation design for integrator systems. Since the use of IEC 61131-3 languages is standardised in the industrial automation programming, the authors consider introducing these languages in the develop of virtual laboratories. The Virtual Laboratory of Automation at the University of Oriente (Cuba) works towards this goal. The SDAI teaching system include model analysis and design in Petri nets, programming and simulation control system in ladder diagrams and sequential functions chart languages. The functional requirements in real installation are verified. The integrate work of all parts is achieved for the use of IEC 1131 graphical languages facilities.