Learnings

Outcomes

WP3 has been completed.  Calculating True Power Factor (TPF) requires that the hardware precisely triggers the voltage and current acquisition at the same time to accurately determine the phase difference between the voltage and current along with respective magnitudes.  The Bushing Data Monitor (BDM) is the hardware responsible for acquisition of current and voltage in the monitoring device used for this project.  

With a regular BDM setup, the bushing and voltage cards are peripherals of the same device. It is therefore possible to guarantee that the device can start the acquisitions simultaneously.  In this project two methods of using a GPS source were used to timestamp data on the separate devices and ensure that any phased shift that is introduced is minimal.  It has been demonstrated that the devices measuring current and voltage can use separate GPS signals and be connected via WiFi to the BDM and calculate TPF.

Recommendations for further work

Further work could allow the wireless voltage reference to be a product for future use in monitoring assets rather than a practical demonstration of a theory.

Lessons Learnt

This project has focussed on 120HC/300HA Trench bushings.  In the course of this project it has been identified that there are two variations of bushing tap connectors.  Any future work connecting to this type of bushing should note the variant required for connecting equipment.

Where weather stations are deployed on sites that are required to communicate with other equipment over a significant distance (~ 100 m) then Wi-Fi repeaters have been found to provide a suitable solution.

Dissemination 

Dissemination activity will be planned when there are more results to report.