Methods and Means of Eddy Current Testing of Soldered Lap Joints of Electrical Machines

This article is devoted to the non-destructive testing of the soldering integrity of soldered lap joints of the current-carrying busbars in electrical machines’ stator windings. The design of a two-element eddy current probe with tangentially positioned coils and active shielding for measuring the soldering integrity of soldered lap joints is developed. This paper considers the method of suppressing the influence of stray parameters on the testing results and the method of correcting the measurements in the case of a deviation in the electrical conductivity of the conductive busbar material. The test results demonstrate the performance of the developed eddy current probe for determining the actual value of the soldering integrity of soldered lap joints in the range of 0–100% with a permissible relative error of no more than 5%.