New method for experimental modal analysis of hydrogenerator's stator core using the excitation from the Poles

Abstract

The study of stator core vibrations generated by electromagnetic forces in electrical machines is of great practical and theoretical interest. An important part of the problem is the correct determination of mode shapes and eigen frequencies of the mechanical system. This work brings to discussion a new experimental modal analysis (EMA) method developed for synchronous machines in which the traditional instrumented hammer impulse is substituted by a magnetic pulse generated by currents applied in two poles. Experimental results obtained in a real 190 MVA hydrogenerator are shown.

Keywords

• stators
• electromagnetic forces
• modal analysis
• vibrations
• synchronous machines
• hydroelectric generators
• mode shapes
• eigen frequencies
• mechanical system
• experimental modal analysis method
• synchronous machines
• traditional instrumented hammer impulse
• poles
• stator core vibrations
• electromagnetic forces
• electrical machines
• great practical interest
• theoretical interest
• correct determination
• hydrogenerator
• EMA method
• magnetic pulse
• apparent power 190.0 MVA