Abstract:In order to measure the revolving rotational speed of the variable displacement piston pump of servo power plant precisely,a miniaturized Hall-type rotational speed sensor which has the characters of hypersensitive,anti-interference,high reliable and wide temperature range is designed. In allusion to the disadvantage of the inductance type transducer,such as the low sensitivity and the bad capacity of resisting disturbance,a design approach of the Hall-type rotational speed sensor is presented. The specialty of hall circuit,which is hypersensitive to the magnetic field signal is utilized. Besides,a high threshold voltage transformational circuit is used to enhance the characters of hypersensitive and anti-interference of the hall circuit. According to the task demands,a miniaturized design is proceed,a kind of material which has wide temperature range is selected and a derating design is used. On the basis of experimental verification,the Hall-type rotational speed sensor can measure the rotational speed of the full range of the electrical machine (from slow to quick) accurately. The sensitivity of the rotational speed senor doesn’t change with the rotational speed of electrical machine and unaffected by the external magnetic field. The parameter performance meets the requirements of the model. This kind of Hall-type rotational speed sensor has a broad application prospects.
