Caracterizador de propriedades elétricas de materiais com acesso remoto

Abstract

With new emerging technologies and increasingly widespread connectivity, old concepts of robust instrumentation equipment need to be updated. With the current tools and the world in our hands through smartphones, it can be said that having total control of the various existing commands to perform actions that occur inside a house, for example, while variables such as temperature and lighting inside this house are viewed simultaneously, has become a simple task. The possibility of remote access brings a great advantage to characterizing instruments by allowing them to operate remotely, eliminating the need for the operator to remain confined in a chemical analysis laboratory while tests with electrolytic solutions harmful to health are being performed, provided that the operator has full control of the process and can analyze the events that are occurring as the energy potentials are applied. Forsuch equipment to be designed, there needs to be an intermediator capable of reading process variables and making control decisions while communicating with the smartphone, sending and receiving such variables. The intermediator is a microcontroller, a component of low power and high processing power. By making use of converters that transcribe binary numbers into a corresponding voltage signal, this microcontroller can draw the most diverse types of power waveforms imaginable, from constant voltages to lagging sinusoids operating at high frequency. However, these converters operate at low voltages and low currents, só a voltage and the current gain stage are necessary for the equipment to be viable for instrumentation purposes. These gains are provided in separate modules, through the use of operational amplifiers and power transistors. Once these challenges were overcome, it was found that the resulting equipment is capable of powering high-power threephase circuits and has excellent reliability and accuracy, with errors below 0.5% even when no fine-tuning is performed. Moreover, it has enormous programming flexibility and integration with other modules that make it versatile equipment for application in other areas of instrumentation, which can range from a simple power supply to PID controllers, provided the proper adjustments are arranged. The components used in the work are easily found in electronic component stores and have low acquisition values, making the manufacturing of the equipment easier due to its low-cost production, but with an extensive range of applications.