The auxiliary inductor plays an important role in the blower system. Apart from reducing ripple current in the capacitor bank it also limits current rise during SCR misfire conditions. This has the secondary effect of stabilising the DC link voltage.
In the event of an external instability e.g. a GTO of the main drive system misfires thereby loading up the alternator and ultimately distorting the wave form that the auxiliary inverter control board sees, a 10mH inductor can effectively mask any side effect of the distorted wave form. This is achieved by allowing complete cycles of the input voltage to be applied to the inductor capacitor filter network without significantly increasing the DC link voltage or the current through the conducting SCR’s.
The advantage of a larger auxiliary inductor is that it will stabilise the DC link voltage and limit SCR current during abnormal external events.
Original auxiliary inductors will measure at around the 3.5 – 6mH.
The much higher inductance of the CTI auxiliary inductor has been achieved by combining toroidal technology and the selection of specific core material.
Mounting and connection points have been maintained as per the original unit but the CTI auxiliary inductor will be supplied with longer mounting bolts.