Abstract: A kind of dual-redundancy LVDT displacement sensor and its converting circuit are introduced. To achieve dual-redundancy displacement measuring by the structure in series and the function in parallel, the differential transformer with series redundancy structure is designed. To solve the problems of low linearity which is the inherent characteristics of series dual-redundancy LVDT displacement sensor and unable to meet the target requirements of system, the method of digital fitting is used to measuring parameters. Then the linearity of measurement signal and control precision of system are improved; debugging time is shortened; efficiency is enhanced and the requirements of high reliability for the control system of new generation are met.

Key words: Dual-redundancy, LVDT, Displacement sensor