It has been
demonstrated that the state of health of insulation can be
evaluated on-line during machine operation with measurement of
equivalent ground-wall capacitance, by measuring the commonmode leakage current generated by common mode voltage of
standard two-level PWM converters. Low cost implementation of
the monitoring system is key to wide adoption in industry. In this
paper, inexpensive off-the shelf current sensors are evaluated for
use in leakage current monitoring. A full low cost system is
designed, built and tested. The testing emphasis the both the short
term precision and long term accuracy of the measurement. It is
shown that it is possible to use low-cost sensors for long term
monitoring, with acceptable compromises
I. Tsyokhla, A. Griffo, J. Wang
IEEE Energy Conversion Congress and Expo ECCE 2019