Power consumption is an important issue on network-on-chip, especially in dynamic systems under different input traffic patterns. It has been proposed that a central controller be connected to all switches for network-on-chip control. This thesis project designs the control function of the central controller, which dynamically changes the network frequency, to minimize the link power on network channels. Control theory is adopted in the design process to provide a systematic approach. Uniform and b-model traffics with various parameters are used in the simulation to test the performance of the control function. The results show that the control function always works properly with acceptable response under both traffic patterns with different resource emission probabilities and b parameters. It can also be adapted to network with different sizes. Arguments in the control function can be modified to fit different situations if necessary. Sammanfattning Strömförbrukningen är en viktig parameter för network-on-chip, särskilt i dynamiska system med varierande trafikmönster. Det finns förslag på en central kontrollenhet