It is very hard to explain it to you briefly.
First of all there is no software that can automatically carry out a calculation of reactive power compensation.
The most important of parameters are:
1) in which the voltage level of compensation is done.
2) what kind of compensation you want. (for your factory is better to dynamic reactive power compensation with thyristors.)
3) which type of electrical consumers is necessary to compensate.
4) single-pole electric scheme of the plant (factory).
So I am at you complete disposal for any additional help and questions.