Application of a dynamic thermal rating system to a 132kV distribution network

Abstract

This paper presents learning points from the application of a dynamic thermal rating (DTR) system to a 132kV distribution network. The DTR system incorporates over 90km of 132kV overhead lines and is being deployed to facilitate the connection of in excess of 200 MW of wind generation. The benefits and principles of this DTR system are stated, and initial results from the deployment are presented.The system architecture is discussed and the process by which it evolved from a single-circuit field trial to a geographically disperse system, covering seven meshed circuits, is described. Key elements of the DTR system approach include (i) the system architecture (using intelligent remote terminal units (RTUs) to process and condition the system data); (ii) the system data requirements; (iii) the methodology used for locating the meteorological stations (which underpin the DTR system); (iv) the use of direct conductor temperature sensors to provide additional thermal visibility of the network; and (v) the requirements to ensure that long-term system reliability is maintained, whilst also considering the repeatability of the system for other network areas. The experiences described in this paper may serve as a useful reference for any other DNOs looking to adopt DTR systems.

Export cable rating optimisation by wind power ramp and thermal risk estimation

“…The alternative to the static cable ratings is the well-know dynamic rating calculations, which, estimate the amount of power that can be accommodated in real-time given measured conditions around the cable [6,7]. Several dynamic rating methodologies have been widely studied and validated in [8][9][10] for land cable installations proving to improve load capacity compared to static ratings [2]. Nonetheless, the application of the existing real-time rating algorithms in offshore export cables could not generate similar benefits because the load current in an offshore cable is not driven by demand but by variable wind power generation availability.…”

De-risking the implementation of real-time thermal ratings

“…The maximum current, and hence real-time thermal rating, for a given operating temperature is calculated by solving the energy balance between the heat generated in the conductor by the Joule effect (I 2 R) and the thermal exchange on its surface. The thermal exchange of the overhead line is dependent on the heat transferred to the conductor by solar radiation (Q S ) and dissipated to the environment through convective (Q C ) and radiative (Q R ) mechanisms, as given in (2).…”

“…Scottish Power Energy Networks (SPEN), the UK DNO, is working with Parsons Brinckerhoff, GE Energy, Nortech Management Ltd and Skye Instruments to deploy a real-time thermal rating scheme that covers >90km of the existing North Wales distribution network, providing the connection point for several prospective wind farm developments [2].…”

Enhancing PV Hosting Capacity Using Voltage Control and Employing Dynamic Line Rating

“…Reference [39] has demonstrated the capacity benefits of dynamic ratings in distribution networks for wind power expansions and the results have depicted an increment of wind power resources by 1.2 times through the same. The distribution network project applying the DLR in [40] has been presented that the implementation of real-time thermal ratings could facilitate the integration of more wind energy sources into the network.…”