Monitoring Low Voltage Electrical Networks Using Low Cost PMUs: a Case Study

This article presents further development of a Phasor Measurement Unit (PMU) prototype, whose main goal is to monitor low-voltage networks using low cost equipment, aiming at a large scale deployment. The device is built around an ARM-based board and commercially available modules. Two units were assembled, calibrated and tested according to the guidelines of IEEE standards. A case study ensues where three experiments are carried out: a comparison with a commercial PMU device, the recording of an interconnected power system event and a low voltage test with controllable loads. The results show that the device (costing between US$ 100.00 and US$ 150.00) can be used to monitor low voltage networks as well as frequency events in interconnected power systems.