The present invention is directed to a method of detection of topology changes in electrical networks, an electrical network communication modem and computer program for monitoring an electrical network topology model for network control, the electrical network comprising a plurality of communication paths, a plurality of switches on the communication paths, a plurality of power measurement devices, and a plurality of frequency analysis devices, the method comprising the steps of installing a plurality of couplers in the electrical network, wherein the couplers are installed such that at least one switch is present on a communication path between two successive couplers, and wherein the two successive couplers are a transmitting coupler and a receiving coupler, transmitting a signal generated via the transmitting coupler on the communication path between two successive couplers, measuring a received power at the receiving coupler via one of the power measurement devices, processing the signal received at the receiving coupler via one of the plurality of frequency analysis devices, deriving information regarding a state of the switch present on the communication path between two successive couplers, and updating a network topology model for network control based on the desired state of the switch.