0000000000297433
AUTHOR
A.e. Navarro
showing 5 related works from this author
Design of a virtual instrument for water quality monitoring across the Internet
2001
Abstract This article presents the design of a new distributed and multi-platform system for water quality monitoring, enhanced with powerful Internet capabilities. The measured variables are temperature, turbidity, pH, dissolved oxygen, and electrical conductivity. The signal-conditioning block has been simplified through the use of software routines for thermal compensation, hence, reducing the cost and dimensions. The system offers a wide variety of Internet capabilities, like e-mail alarm notifications, automatic storage of measured data in a remote machine via the FTP protocol, dynamic generation of HTML reports, real time graphs, and indicators visible from a remote web browser, etc. …
Control circuit design of the L-LC resonant inverter for induction heating
2002
In this article, the frequency variation control strategy for an induction heating L-LC resonant inverter is analyzed. The control consists of three loops, which are analyzed and reduced to their corresponding small-signal block diagrams. From these diagrams, the optimal structure of the compensation network and the design boundaries for first order closed-loop response are derived. The special case of phase limitation is analyzed because it is unstable in open-loop operation. Finally the implementation of the control circuit is described and experimental results are shown.
ISFET drawbacks minimization using a novel electronic compensation
2004
Ion sensitive field effect transistor (ISFET) and membrane field effect transistor (MEMFET) have some drawbacks related to: long-term drift, hysteresis and thermal drift. These factors limit the accuracy of ISFET/MEMFET based measurements systems, specially for continuous or long period measurements. Due to its accuracy, repeatability and easy-to-use features, electronic instrumentation systems are the best tools to design ISFET/MEMFET based measurement systems. A well-designed hardware and a qualified virtual instrumentation software are the key factors to overcome and compensate hysteresis, thermal and long-term drifts ISFET/MEMFET limitations. The paper is dedicated to show an instrument…
Novel voltage-controlled conditioning circuit applied to the ISFETs temporary drift and thermal dependency
2003
This paper describes a novel conditioning circuit applied to ion-sensitive field-effect transistors/membrane-ion-sensitive field-effect transistors (ISFETs/MEMFETs) sensors. The novel conditioning circuit allows the sensor polarization with the needed either voltage or current required in each application, thanks to two completely independent voltage-controlled blocks (current and voltage blocks). The control of the voltage block is the most critical point in our design because the voltage block maintains the sensor feedback stable, avoiding the thermal and temporary drifts of the sensor feedback.
A new efficiency low mass bi-directional battery discharge-charge regulator for low voltage batteries
2002
Since the policies of the space agencies are focused on the development of smaller satellites, it is becoming more and more important the save of volume and mass in the necessary satellite equipment. Due to this need, the authors introduce a bi-directional battery discharge-charge regulator for low voltage batteries that reaches these new goals and besides which has high efficiency.