HYB25-39
Control of Offshore Hybrid Power Plants Considering Aggregation of Plant Technologies
02 HYB25-39
Presented by: Aivaras Celna
1 Ørsted Wind Power A/S
2 DTU Wind and Energy Systems
Hybrid Power Plants (HPPs) are growing in popularity and have received more attention from technology OEMs, RES developers and grid operators. One of the primary motivations for HPP development is a reduction in power variability and an increase in the capacity factor, due to minimized need for curtailment[TS1] . Moreover, HPPs with individual technologies connected behind a single point of connection allow a reduction in cost due to improved utilisation of electrical infrastructure and enhanced participation in electricity markets by improved capabilities for the provision of ancillary services. With the increasing market for offshore wind power plants and the emergence of new concepts such as energy islands, large-scale HPPs with one or more offshore sub-plants are coming up, e.g., the Hollandse Kust project in the Netherlands (combination of offshore wind and storage). As the control of large offshore WPPs is already a complex task, it is crucial to investigate how to control HPPs consisting of offshore WPPs and other technologies.
To harvest HPPs' potential, individual asset dispatch and control must be coordinated. Centralised (hierarchical) control has gained[TS2] the most attention for HPP applications. HPP hierarchical control architecture usually involves three control layers: the highest - hybrid power plant controller (HPPC), sub-plant controller and lowest - asset controller, where the control function and responsibility domain at the HPP, plant and asset level are addressed accordingly. The higher-level controllers are responsible for dispatching control commands to the lower layers. Such control is well established in power systems, and some recent work on its application on HPPs can be found in the literature. However, all published HPP-related work (to the authors' knowledge) concerns the onshore-based HPPs and assumes that the distance between co-located sub-plants is short or negligible.
Large-scale HPPs consist mainly of inverter-based resources (IBRs), and large offshore WPPs have many turbines with complex power collection systems. Thus, modelling such a detailed system becomes a cumbersome, difficult to troubleshoot, long and computationally heavy task. Therefore, this research work explores whether the applicability of aggregation methods such as power loss or voltage drop can be accurately used for HPP modelling with offshore technologies. Furthermore, aggregation simplifies the studies and allows us to investigate whether the same onshore-based HPP hierarchical control architectures can be applied to offshore HPPs.
The work results show that aggregation of individual technologies can be achieved with reasonable accuracy, as presented by performed load flow analysis for detailed and aggregated systems. The aggregated HPP model is also suitable for investigating high-level hierarchical control architectures, even though some interactions between plant assets are lost. Finally, the challenges and limitations of the readily available onshore HPP hierarchical control architecture are highlighted, revealing limited applicability for offshore HPPs and providing suggestions for improvements.
To harvest HPPs' potential, individual asset dispatch and control must be coordinated. Centralised (hierarchical) control has gained[TS2] the most attention for HPP applications. HPP hierarchical control architecture usually involves three control layers: the highest - hybrid power plant controller (HPPC), sub-plant controller and lowest - asset controller, where the control function and responsibility domain at the HPP, plant and asset level are addressed accordingly. The higher-level controllers are responsible for dispatching control commands to the lower layers. Such control is well established in power systems, and some recent work on its application on HPPs can be found in the literature. However, all published HPP-related work (to the authors' knowledge) concerns the onshore-based HPPs and assumes that the distance between co-located sub-plants is short or negligible.
Large-scale HPPs consist mainly of inverter-based resources (IBRs), and large offshore WPPs have many turbines with complex power collection systems. Thus, modelling such a detailed system becomes a cumbersome, difficult to troubleshoot, long and computationally heavy task. Therefore, this research work explores whether the applicability of aggregation methods such as power loss or voltage drop can be accurately used for HPP modelling with offshore technologies. Furthermore, aggregation simplifies the studies and allows us to investigate whether the same onshore-based HPP hierarchical control architectures can be applied to offshore HPPs.
The work results show that aggregation of individual technologies can be achieved with reasonable accuracy, as presented by performed load flow analysis for detailed and aggregated systems. The aggregated HPP model is also suitable for investigating high-level hierarchical control architectures, even though some interactions between plant assets are lost. Finally, the challenges and limitations of the readily available onshore HPP hierarchical control architecture are highlighted, revealing limited applicability for offshore HPPs and providing suggestions for improvements.