Error characteristic and its compensation method for GECS measurement system

The principle and measurement systems of grating eddy current sensor (GECS) are introduced in this paper. To improve accuracy of GECS, error sources and error characteristic are thoroughly analyzed. Conclusion is drawn that this sensor has a series of error sources including deficiency from sensor design, inaccuracy of the sensor fabrication, dispersiveness of electronic component parameters, etc. Furthermore, a new segmental line compensation algorithm based on the method of least squares curve fitting is presented as a result. Experimental results show that this algorithm needs fewer amounts of compensation data so that it not only solves insufficient MCU RAM resources, but also achieves high error correction performance, which lays a solid foundation for practical application and industrialization of GECS.