This master thesis focuses on the effect of variabilities in a Power & Free conveyor system on the flow continuity by an analysis on the product, process and production level (3P), a discrete-event simulation model and the theory of Cyber-Physical Production systems (CPPS) to control the product flow. Scenarios were evaluated with this model and the results show the effect of performance increase when variability decreases. Requirements are set to come to real-time control by developing this model into a digital twin as part of a CPPS. It can be concluded that the discreteevent model can be used to predict the performance and take control measures accordingly, subsequently real-time control is possible by implementing real-time sensor measurements in the model, thereby developing the model into a digital twin.