Abstract
The increased integrations of intermittent renewable energy sources into power systems cause more power grid congestions and therefore system operators need more advanced control to relieve this pressure. The dynamic thermal rating (DTR) system is able to increase the thermal constraint and subsequently maximum loading of existing lines. This dynamic rating is achieved through real-time considerations of weather data and it is usually much higher than the traditional static thermal rating system. The operational tripping scheme (OTS), a variant of the wider system integrity protection scheme, also relieves line congestions but it does this by tripping pre-selected generators and this have the unwanted consequence of reducing power adequacy. This paper proposes the novel integration of DTR and OTS, while considering the inherent uncertainties of their sensors based on fuzzy numbers, to avoid unnecessary generation tripping due to conservative line ratings. This novel Fuzzy-DTR-OTS delays the tripping of generations, enhances the adequacy of power supply, improves system security and avoids high risk cascading black out inducing events.
Highlights
The growing demand of electricity and awareness for cutting CO2 emissions to curb global temperature rise has drastically increased the integrations of intermittent renewable energy sources such as wind [1]–[4] and solar [5]– [8], energy storage systems to support renewables [9]–[11], demand response to actively manage load profiles [12]–[17], electric vehicles, FACTS devices for voltage and reactive power regulations and HVDC transmission corridors for long distance power transfer
Instead of triggering protection systems based on fixed thresholds, system integrity protection scheme (SIPS) dynamically adjusts the thresholds in realtime according to critical grid conditions that are monitored through various sensors
The specific Operational Tripping Scheme (OTS) considered in this paper is the generation rejection scheme (GRS), which trips generators after transmission line outages to prevent further unwanted cascading line outages, and this is possible as the tripping of specific generations would avoid sequential overloading on remaining lines, and instability altogether, and return grids to a secure operational state [23]
Summary
The growing demand of electricity and awareness for cutting CO2 emissions to curb global temperature rise has drastically increased the integrations of intermittent renewable energy sources such as wind [1]–[4] and solar [5]– [8], energy storage systems to support renewables [9]–[11], demand response to actively manage load profiles [12]–[17], electric vehicles, FACTS devices for voltage and reactive power regulations and HVDC transmission corridors for long distance power transfer. Modern power systems have become more complex and challenging to operate, which is due to higher number of faults on transmission networks, operations that are closer to security limits, and higher emphasis of reliability, economic and environmental factors that are all difficult to optimize together [18] In view of these challenges and uncertainties, there is a need for effective plans that can restore grid integrity to normal conditions as fast and as closely as possible with reasonable cost during contingencies, and the system integrity protection scheme (SIPS) fits this set of criteria [19]. The key benefit of deploying the DTR-OTS system is an improved understanding of conductor temperatures, and this new found information can be capitalized to optimally trip generations at the right time, to maximize line loadings and power deliveries, and to provide greater situational awareness to system operators [31].
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have