This a a larger version of the Philips MB12 type motor. Whilst it is rated with a high torque it does have significant angular speed variation. It may be possible to find improvements at different operating points, however the fundamental angular speed variation due to the design are not going to go away….
50Hz Mains.
60Hz clean supply and phase shift capacitor.
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60Hz Tuned phase – the 120Hz peak is still dominant (about 9dB better than the capacitor shifted operation) and is a reflection of the rotor speed variation.
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Speed plots – only 1/4 of a revolution plotted for clarity.
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