IDOC Generation big scale

Hi guys, I am new in this comunity and I need your help.

I work with external system that comunicate directly SAP by IDOC.

My problem: To my system work correctly, some registers must be in my database like delivery, purchase orders, sales order and "notas fiscais" (Brazil).

How can I do generation a mass of IDOC with this types? There are some standard sap tcodes to do that?

Att,