Narrowband powerline communication (NB-PLC) systems represent a key step for the real development of smart grids’ applications in the medium voltage (MV) and low voltage (LV) networks. This article sums up the results of a complete experimental measurement campaign aimed at investigating the low voltage NB-PLC channel in the frequency range from 9 to 500 kHz in various sites (i.e., rural, urban etc.) located in France. The noise features in time-frequency representation are studied at five different sites between the transformer substation and the smart electricity meter. The main contribution of this study consists in estimating the theoretical channel capacity which constitutes a major interest for the users and actors of the electrical system. The channel capacity calculation shows reliable results in the US Federal Communications Commission (FCC) band (a few Mbits/s). The quality of the communication in the FCC band enables to integrate new smart grids’ applications and services based on the existing NB-PLC communication for advanced metering infrastructure (AMI).

Controlling the cost of electricity consumption remains a major concern, particularly in the residential sector. Smart home electricity management systems (HEMS) are becoming increasingly popular for providing uninterrupted power and improved power quality, as well as for reducing the cost of electricity consumption. When power transfer is required between a storage system and the AC grid, and vice versa, these HEMS require the use of a bidirectional DC–AC converter. This paper emphasizes the potential value of an almost unexplored topology, the design of which was based on the generation of sinusoidal signals from sinusoidal half waves. A DC–DC stage, which behaved as a configurable voltage source, was in series with a DC–AC stage, i.e., an H-bridge, to achieve an architecture that could operate in both grid and off-grid configurations. Wide bandgap power switches (silicon carbide metal-oxide-semiconductor field-effect transistors [MOSFETs]), combined with appropriate control strategies, were the keys to increasing compactness of the converter while ensuring good performance, especially in terms of efficiency. The converter was configured to automatically change the operating mode, i.e., inverter or rectifier in power factor correction mode, according to an instruction issued by the HEMS; the latter being integrated in the control circuit with automatic duty cycle management. Therefore, the HEMS set the amount of energy to be injected into the grid or to be stored. The experimental results validate the operating modes of the proposed converter and demonstrate the relevance of such a topology when combined with an HEMS, especially in the case of an AC grid connection. The efficiency measurements of the bidirectional DC–AC converter, performed in grid-connected inverter mode, show that we exceeded the efficiency target of 95% over the entire output power range studied, i.e., from 100 W to 1.5 kW.

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