In the master’s thesis we have described bearing currents in details. As a result of the converter type of a power supply they adversely affect the operation of the asynchronous motor or in relatively short period of time degrade or even damage the bearing of the motor.
Based on literature we have examined several causes of bearing current’s formation, how to measure them correctly and how to limit or eliminate them. In the first theoretical part, we defined and explained different types of bearing currents. In the second part, we described the procedures for measuring currents based on findings of other authors. Then we tried to find some procedures to eliminate unwanted bearing currents, which we have also supported with simulation models. Lastly we have performed practical measurements in the laboratory and in industry.
Since bearing currents are encountered on a particular industrial drive causing production shutdowns and more frequent maintenance, the purpose of the thesis is to find an adequate solution to eliminate unwanted currents.
We have focused on converter settings, grounding execution and application of two types of output filters. At the end of the thesis we described the measurement results in details and listed adequate solutions and improvements.
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