Graciela Mabel Toccaceli

An embedded system for evoked biopotential acquisition and processing

This work presents an autonomous embedded system for evoked biopotential acquisition and processing. The system is versatile and can be used on different evoked potential scenarios like medical equipments or brain computer interfaces, fulfilling the strict real-time constraints that they impose. The embedded system is based on an ARM9 processor with capabilities to port a real-time operating system. Initially, a benchmark of the Windows CE operative system running on the embedded system is presented in order to find out its real-time capability as a set. Finally, a brain computer interface based on visual evoked potentials is implemented. Results of this application recovering visual evoked potential using two techniques: the fast Fourier transform and stimulus locked inter trace correlation, are also presented.

RDG in weak grid for desalination plant. System topology and control strategy

Renewable Distributed Generation (RDG), such as production of electric power near to the load, is particularly beneficial when the distribution network is “weak” against specific demands, as in potable water production systems connected to coastal electrification networks. In these areas, the wind resource may be suitable for this type of generation. This work proposes the topology, the operation mode and the control strategy for a Reverse Osmosis Desalination Plant, “assisted” by a weak AC grid and “powered” by a variable speed wind turbine based on a three-phase BDFIG machine. The wind energy conversion is optimized through adequate control of the generator. The high pressure pump of the desalination plant is controlled for the maximum utilization of the generated power. The electric power fluctuations due to win turbulence are compensated through a controlled energy storage system based on a flywheel. The system configuration, its operation mode and control are presented.

A microgrid with EMS based on a standard data network. Analysis and evaluation

In order to achieve optimal operation conditions in a microgrid with Energy Management System (EMS), a communication system is needed. It is important to consider in depth different characteristics of communication systems regarding issues like determinism, time constrains, cost effectiveness etc. This paper reviews different type of network protocols which can be used in order to fulfill the different communication needs for protection, management and automation in a microgrid. We also present simulations about the behavior of different networks protocols, showing whether some of the above conditions are met or not.

An Embedded Hybrid BCI Speller

The present work proposes an embedded real time hardware-software platform for brain computer interfaces (BCI) based on steady state visual evoked potentials (SSVEP) and alpha rhythm. The complete implementation of the embedded system is described, including the electroencephalogram (EEG) amplifier, signal acquisition and processing stages, and practical implementation. The device is a 25 characters hybrid-BCI speller that uses 5 visual stimulus and visual alpha waves for control instructions. The system focuses on simplicity and portability, using only two electrodes, a simple EEG amplifier and an embedded computer. The speller does not require any training from the user and provides real time biofeedback to increase attention on stimuli. The platform is based on an embedded system with a real time operative system, Windows CE. Experimental results are presented in order to show the feasibility of the proposed system.

Stand-alone hybrid microgrid for remote areas. Topology and operation strategy

In remote regions, were a main Utility System for energy distribution is not available, the implementation of Microgrids with hybrid generation are very useful. In this context, a Stand-Alone wind/diesel/gas/battery/supercapacitors Hybrid Microgrid topology is proposed. The main scope is to create a low cost system to feed Residential loads through a local AC bus, using wind energy obtainable at system location. The random characteristics of the wind makes necessary to smooth the fluctuating supply in order to minimize the disturbances on local grid electric parameters. To overcome these problems, a Wind Turbine based on a DFIG machine and Strategies to control the power of a Storage Energy System are employed. An appropriate Supervisor Module with a reliable communication network is used to balance generation and loads, in order to properly operate the Microgrid. The system structure, operation modes and mathematical models for simulation and validation are presented.

Barcode reader sensor based on optical navigation technology

The Waste Electrical and Electronic Equipment (WEEE) cause a major ecological problems. This paper shows how to reuse an optical mouse and CD reader into disuse in the implementation of a linear low-cost scanner to be used for educational purposes. The heart of the device, the ADNS2610 sensor of AVAGO, has ability to record images in grayscale. It is equipped with optical navigation technology for computer mouse applications among other possible uses. The mechanical part of a CD reader is also rescued to perform the linear movement of the scanner.

Microgrid for remote areas with Water Pumping, based on wind-diesel DER and Energy Storage

In remote regions were a main distribution grid is not available, the implementation of Microgrids with Distributed Energy Resources (DERs) are very useful. In this context, a Stand-Alone Wind/Diesel Microgrid with modular architecture is proposed. The main scope is to feed Residential loads and a Water Pumping System through a local AC BUS. The random characteristics of the wind makes necessary to smooth the fluctuating supply in order to minimize disturbances in the pump and diesel generator. To overcome this problem, a compensation control strategy based in the power control of a Storage Energy System and the Water Pumping System is employed. An appropriate and reliable communication network is used to supervise and balance generation and loads, to maintain the correct functioning of the Microgrid. The system structure, operation and mathematical models for simulation and validation are presented.