Refinement is a powerful mechanism for mastering the complexities that arise when formally modelling systems. Refinement also bringswith it additional proof obligations -- requiring a developer to discover properties relating to their design decisions. With the goal of reducing this burden, we have investigated howa general purpose automated theory formation tool, HR, can be used to automate the discovery of such properties within the context ofthe Event-B formal modelling framework. This gave rise to an integrated approach to automatedinvariant discovery. In addition to formal modelling and automatedtheory formation, our approach relies upon the simulation of systemmodels as a key input to the invariant discovery process. Moreover we have developed a set of heuristics which, when coupled with automated proof-failure analysis, have enabled us to effectively tailor HR to the needs of Event-B developments. Drawing in part upon case study material from the literature, we have achieved some promising experimental results. While our focus has been on Event-B, we believe that our approach could be applied more widely to formal modelling frameworks which support simulation.