José Miguel Ramírez Scarpetta

OPTIMAL U/f CONTROL FOR INDUCTION MOTORS

Abstract This article presents a methodology to find an optimal U/f curve that minimizes the energy consumption in induction motors that drive loads where the torque is proportional to the square of the speed, such as centrifugal pumps and fans; the experimental results presented here validate this methodology.

Design and construction of an energy management system for electric vehilce batteries

An user programmable power management system oriented on designing custom charging and discharging profiles for electric vehicles batteries was designed and tested. The charging process is in charge of a Buck converter controlled by a selective current/voltage controller with bumpless control transfer, and supplied by a configurable AC-DC converter that could use both single-phase and three-phase source. For battery discharging, a MOSFET working as a dynamic resistor is used. This power management system was tested programming a fast charging on a 12V sealed lead-acid battery and a low charging using one and two 12V gel batteries in a series array. Also was tested emulating an electric motorcycles engine and discharging a 24V gel batteries array according to a given drive profile.

Virtual tools for remote analysis and simulation

This document describes a general structure for the implementation of virtual tools for remote calculation through Internet. Two virtual tools for mathematical analysis (Analys) and simulation of dynamic systems (SimWeb), supported by the Matlabcopy, are described. These virtual tools, permit access to the Matlab from multiple work stations, without distance, power computer restrictions or users knowledge in Matlab language; in a similar way, they allow the simulations of block diagrams through a friendly user interface. The remote calculation tools have low cost of implementation, allowing to obtain a system of high calculation power and accessible for a great number of users. The tools are oriented to automatic control systems analysis and simulation, but their use is expandable to other fields of engineering and basic sciences