adjustable IGBT current?
With an inductive load and PWM.

IGBT's are optimised to be Discrete ON or OFF devices and do not have a linear/active region like MOSFET's and BJT's.

The CS8312 shows an example setup with an inductive load and a sense resistor.

This particular chip works by increasing the threshold by 45%


  Changing the CLI pin from a logic low to a logic high increases the
  FLAG turn on voltage by approximately 45% and the regulation sense
  voltage by approximately 39% respectively.


Other methods are via simple comparator for hysteresis control or PI controller to then generate a PWM signal that is indirectly used to drive the IGBT