Investigation of the precision and accuracy of RVDT interfaces for flight control applications

Rotary Variable Differential Transformers (RVDT) is a form of sensor used for measuring the angular displacement of moving objects. Because of its robustness and simple design, the RVDT is popular to use in the aviation industry for flight control systems. This thesis investigated the precision and accuracy of an analog signal conditioning circuitry for RVDTs. The study evaluated two AC/DC converter designs based on full-wave rectifiers implemented with operational (OP) amplifiers. Measurements were conducted using a simulated RVDT across an angular range of -40º to +40º, and under the temperature conditions from -25ºC to +85ºC. Results showed that the second AC/DC Converter design achieved the highest accuracy with angular errors within ±0.07º, fulfilling the desired requirements. The study concludes that OP amplifier-based full-wave rectifier solutions can be constructed with high accuracy for avionic applications.