The paper presents a virtual instrument based on a quasi-balanced bridge designed to measure the parameters of an inductor, a capacitor or a resistor. The unknown element, in series with a reference resistor, forms the real half of an ac bridge, while the software model of a resistive potentiometer shapes the virtual half. Actually, one acquires the supplying voltage and the voltage across the reference resistor respectively, after which these signals are digitally processed according to the quasi-balanced bridge algorithm. Both the hardware and the software of the prototype model are described. The experimental results and the error analysis are also presented.
展开▼
