Due to the large-scale implementation of distributed generation, the power delivery system is changing gradually from a "vertically" to a "horizontally" controlled and operated structure. This transition has prompted the emergence of the active distribution network (ADN) concept as an efficient and flexible distribution system to deal with various challenging issues. This paper addresses a multiagent system (MAS) as a suitable technology to manage autonomous control actions and perform the coordination in an ADN. In this agent-based ADN a smart power router is implemented, which can flexibly integrate network areas and optimally manage power flows. Operational and control functions of the power router has been investigated in a laboratory experiment. In this lab setup, a configuration of the power router is established in a combination of a three-inverter system and an agent. The experiments show that the ADN can operate in an efficient and flexible way with the support of the power router interface. The control function of the inverters and the operation of MAS are thoroughly verified.