The Project involves the development, real-world testing and continuous refinement of a combined hardware and software system that provides real time status of a transmission line enabling accurate calculation of a dynamic line rating (DLR) for a transmission line.
The rating of a transmission line refers to its design current-carrying capacity based on the thermal capacity of the conductor. Conductor thermal ratings act as limits on the magnitude of electrical current passing through the line and hence the total power that can be transmitted. Excessive conductor temperature causes the conductor to sag beyond its required limits and can reduce the life of the conductor if subject to regular overheating. Sag must be managed to maintain statutory clearance limits from vegetation, infrastructure and the ground, ensuring the line does not cause a public safety or environmental risk. The thermal capacity of conductors can be significantly impacted by environmental conditions such as wind and ambient temperature.
To determine a line rating, Transmission Network Service Providers (TNSPs) in Australia typically consider the material properties of the conductor and then utilise a set of broad assumptions for environmental conditions in the region of the transmission line. For example, typical temperatures and wind speeds during night, day, summer and winter, produce a ‘static’ line rating commensurate with the conditions. Static line rating operating process is standard industry practice, as existing technology solutions that provide real-time data of circuit status to TNSPs are limited and expensive. This results in the underutilised capacity of transmission network assets.
The system being developed, also referred to as the Next Generation Dynamic Line Monitoring System, will provide valuable data on real time status of the transmission line circuit. The system can be integrated into the energy management systems employed by TNSPs and enable improved dynamic line rating systems performance. The benefit of increased capacity is realised by providing greater dispatch of renewable energy resources under AEMO control. The system will be installed by remotely piloted aircraft systems, or drones.
The Project will involve:
- Completion of final transmission line sensing units design and prototype manufacture.
- The manufacture and field trial of at least 20 transmission line sensors units on a live transmission line with TransGrid providing technical support and feedback.
- Completion of associated software and user interface to view all critical information associated with the circuit that enables increased dynamic capacity.
- Knowledge sharing deliverables as agreed with ARENA, including lessons learnt reports detailing the regulatory, commercial, and technical findings of the Project and final report detailing overall Project learnings including outcomes of the TransGrid trial.
The Project outcomes are:
- Reducing barriers to renewable energy uptake through developing technology that will enable the network operator to unlock additional transmission capacity to facilitate dispatch of a greater volume of renewable energy generation resources, whilst also mitigating grid connection related risk factors inhibiting investment in new-build renewable energy generation.
- Increasing skills, capacity and knowledge related to the thermal capacity of power lines and ways in which latent capacity on the network can be unlocked whilst maintaining system security and stability in the context of high renewable energy penetration.
- Improvement in the technological readiness level and commercial readiness level of Infravision’s Next Generation DLR.
In addition to the benefits of optimised asset utilisation, the real-time data from the Next Generation DLR can provide increased situational awareness for networks and market operators as well as support asset lifecycle monitoring. The device can determine the depth information about the lower conductors as well as vegetation growing upwards from below, therefore having the capacity to detect and take preventative action for potential fire hazards.