Projects:2020s1-2512 A Hard Real-Time ROCOF "thing"

Introduction

Islanding is a condition where a distributed generator continues to power a region, even though electrical grid power is no longer present. Islanding can be dangerous to utility workers, and to equipment. In order to minimise risk, it is important to decrease the time in which an island is detected. One method for achieving this is to measure rate of change of frequency ROCOF, and to look for exceptional deviations.

In 2019 a prototype device was developed, where an Arduino (microcontroller) was embedded inside a Phase-Locked Loop (PLL). The advantage of this approach is that the most difficult part of the computation is carried out an an analogue sense, inside the PLL. This means that ROCOF can be estimated using a very simple digital microcontroller.

Project Team

Students

• Juwan Fernando
• Jude Perera

Supervisor

• Dr. Andrew Allison
• Mr. Salerno (External)

Definitions and Abbreviations

• RoCoF = Rate of Change of Frequency
• PLL = Phase Locked Loop

Aim

To develop a complete working device that can be deployed to any required location on an electrical network. The device must be capable of triggering local action that is safety critical. In this sense, the device must be capable of “Hard Real-Time” action in an “Embedded” environment. We propose the use of a platform that is capable of supporting a true Real-Time Operating System (RTOS), Vx-Works. One possible platform is the Beagle Bone Black. The device must also be capable of reporting conditions and activity back to a central location through an information network. In this sense, the device will be a sensor-node, or “thing”, in an Internet of Things (IoT). Given the safety-critical nature of the possible application, the communication must be secure