Test and comparison of LVDT signal conditioner performance

This paper presents the results of a novel digital signal processor (DSP) based technique for signal conditioning of Linear Variable Differential Transformers (LYDTs). Signal conditioning is achieved through a modified DSP-based Costas receiver. This system is tested and compared with two commercially available analog signal conditioners and a second DSP-based signal conditioner. The system developed by the authors has better dynamic response than existing solutions and better noise rejection than commercially available solutions. Static testing of the system using both 4-wire and 5-wire LYDTs verifies that the conditioner meets or exceeds the linearity performance of existing signal conditioning systems over the full-scale operating range. In addition, this system requires no phase compensation network or manual tuning.