Design of Cost-Effective Power Quality and EMI Sensor for Multinode Network

Multinode measurement systems are required to evaluate electromagnetic interference (EMI) propagation and power-quality (PQ) issues in microgrids or large buildings. PQ issues are a subset of electromagnetic compatibility (EMC), and identifying them can help track down problems in large networks. Commercial-off-the-shelf (COTS) sensors range from cheap smart plugs, with limited functionality and accuracy, to high-end measurement devices. For large-scale deployment and future research, a cost-effective solution is needed for distributed measurements. This letter discusses designing and evaluating a cost-effective PQ sensor that fits the gap between cheap smart plugs and high-end measurement devices. It is designed with expandability in mind while keeping the cost down. This allows the device to log other EMI parameters in the future by adding sensors without redesigning the device. An energy measurement accuracy of smaller than 1% is achieved, comparable to a class B energy meter of the EN-50470 standard. It can measure all the elementary electrical parameters so deviations to the EN-50160 can be logged in a (sub)second scale.