Hi! Check out Wiki https://en.wikipedia.org/wiki/Induction_generator which gives a brief description of induction generators and a worked example. The capacitors "tune" the device and make it work over a wider range of loads.
Practically could be obtained by drawing circle diagram from SC and OC(noload) as induction motor, then complete the circle to full circle to obtained operating points as generator, and from the working power factor as generator and supplied VAR, capacitance value(effect) could be obtained practically......