Aprimoramento da Técnica de Multiplexação no Domínio da Frequência para Acionamentos de Motores Trifásicos

Abstract

Currently, a lot of research is being carried out regarding the activation of three-phase motors for electric and hybrid vehicles. Cars like the Toyota Prius and Nissan Leaf use angular position sensors called resolvers to estimate the speed of your engines. The resolver generates two analog signals modulated amplitude. On the other hand, modern closed-loop control of a three-phase motor requires, in addition to the two resolver signals, the measurement of two currents. Therefore, four analog signals must be digitized. Many digital processors use an analog-to-digital converter with a analog multiplexer to discretize the input signals. The multiplexing in frequency domain was recently proposed to simplify the process of acquisition of signals, but the operating frequency of the resolver chosen in proposals previous studies obtained satisfactory but limited responses. This course conclusion work proposes an improvement in the technique of frequency multiplexing of current sensor signals and solving, through of using high operating frequencies to resolve and synchronize the outputs of the sensor solve with the modulation technique that controls the motor inverter. O result obtained shows that the system response is improved for more poles quickly, thus reducing the transitory period and, due to the proposed system, the error in steady state for higher excitation frequencies. It was then obtained a simpler multiplexing system with signal demultiplexing with greater accuracy than in other works.