Evaluation of the Probability of Supraharmonic Interference in Low-Voltage Networks

Supraharmonics are present in low-voltage (LV) networks, and they can cause interference with equipment and power line communication. The propagation of supraharmonics is defined by the network impedance which in turn depends on the impedance of the devices connected to the network. The probability of interference due to supraharmonics is then dependent on the customers’ behavior. This article presents a case study for the evaluation of the probability of interference considering the uncertainty in LV customers’ supraharmonic emission and impedance. A stochastic analysis of the system characteristics and supraharmonic emission is used. The results for the case study presented in the paper show that there could be a 40% probability of surpassing the compatibility levels in certain nodes which translates into a risk of interference due to supraharmonics. The simulation results are supported by measurements performed in a laboratory, which can emulate a network like the simulated one. The simulation and measurements show that in the frequency range of 27 kHz to 150 kHz the compatibility levels are surpassed.