ANEMÔMETRO BASEADO EM SENSOR TERMO-RESISTIVO OPERANDO A TEMPERATURA CONSTANTE COM AJUSTE AUTOMÁTICO DE FAIXA DINÂMICA

Abstract

The thermoresistive - based hot-wire anemometer operating at a controlled temperature is a classical architecture that is vastly found in the literature. Nevertheless, this architecture may present a problem due to dynamic range variation of its output voltage for significant variation of the fluid temperature. In this work, the classical architecture is revisited and the influence of the fluid temperature is verified. An alternative architecture of a controlled temperature anemometer implemented with a controlled current source with automatic compensation of the fluid temperature influence on the output voltage dynamic range is proposed. Simulations of the classical architecture and of the proposed system using the parameters from a commercial sensor are presented and compared. Results show that the output voltage dynamic range for the proposed architecture employing the automatic compensation is practically constant.