SoC Architecture for High-Frequency Acquisition of Household Electric Signals

Accurate monitoring of current and voltage in residential power grids is crucial for effective energy manage-ment and the implementation of smart technologies for non-intrusive monitoring of persons, especially those with cognitive or physical impairments. The emergence of high-speed analog-digital converters (ADCs) and wireless Internet-of-Things (IoT) devices has significantly improved measurement rates and realtime data collection capabilities, but the acquisition rates for the correct recognition of some devices in a non-intrusive load monitoring (NILM) aplication might still be insufficient. In order to address this issue, this work describes a System-on-Chip (SoC) architecture based on a Field-Programmable Gate Array (FPGA) and a dedicated analog conditioning circuit for household elec-tric signal acquisition. The architecture simultaneously captures voltage with a bandwidth ranging from 500 Hz to 100 kHz; and current signals from 300 Hz to 100 kHz. It is based on a Zybo z7-10 development platform along with an AD7476A ADC and a conditioning circuit, which consist of a filtering stage, an isolation transformer and a voltage-level adapter. The system is adequate for realtime household electric signal acquisition and processing, being able to capture high frequency harmonics correctly, while enabling the possible implementation of further processing, such as the integration of artificial neural networks and/or machine learning algorithms for event classification, load identification, and the implementation of an alarm system for behaviour anomalies.