PROCESS FOR DETECTING AGEING OF A DC BUS CAPACITOR OF A POWER CONVERTER

Method to estimate a remaining of useful life of a DC link capacitor (3) of a converter (1) through determination of a minimum value Clim of its capacitance C under which performances of the converter are considered as insufficient comprising:- implementing a real time model (130, 230) comprising a motor drive model and a capacitor model using decreasing capacitor values (140, 150, 240, 250) to calculate a forecasted minimum capacitance Clim sufficient for keeping at least one of DC voltage ripple, motor current ripple, speed ripple or torque ripple under a specified value;- calculating a time difference between a time Tactual, for which the capacitor has an estimated capacitance based on an ageing curve Ccurve, and a time Tlim for which the capacitor will have the forecasted minimum capacitance Clim, with the use of an ageing curve Ccurve of said capacitor and estimating the remaining useful life of said capacitor Tactual-Tlim (120).