Switch-Driving Eddy-Current Displacement Sensing Based on Power Loss

The principle of a switch-driving eddy-current displacement sensor is analyzed based on the eddy current power loss. This sensor converts the power loss into a working current by using switching circuits, in which a DC current related to the gap is picked out with a low pass filter. The displacement of the target thus could be obtained. A series of static experiments are carried out with iron, aluminum and nonmagnetic stainless steel as the targets, finally giving promising results.