New pathways to future grid compliance for wind power plants

Abstract

Over the last decade, the rapid growth of wind power is driving an increase of efforts in defining the frameworks and rules for the connection of wind power plants (WPPs) through the grid codes and standards, making testing/validation more demanding and complex for wind turbine (WT) manufacturers and WPP developers. Traditionally, WT manufacturers carry out grid compliance tests at full-scale prototype turbines whereas WPP developers and Transmission System Operators (TSOs) mainly perform studies for new WPPs based on offline RMS and EMT simulations. Until now, these strategies have been sufficient for ensuring grid compliance of WTs and WPPs, however moving forward the wind sector needs new testing methods to meet the increasing WT capacity, WPP complexity, and deployment pace to achieve society's desired sustainability targets. In this paper, the emerging strategies that target these challenges are presented as: a) subsystems and component testing of WTs specified in IEC 61400-21-4; b) -hardware-in-the-loop (HiL) real time simulation for WT/WPP control and protection appraisals (future 61400-21-5). Finally, a future outlook is given on the importance of addressing model validation and how these strategies can be complemented with other modern analytical tools such as artificial intelligence/machine learning, data-driven dynamic modelling, digital twin technology, and software-in-the-loop (SiL) real time simulation.

Advancements on Grid Compliance in Wind Power: Component & Subsystem Testing, Software-/Hardware-in-the-Loop, and Digital Twins

“…Upon commissioning and operation of a new WPP, plant models can also be validated for setpoint changes and faults existing in the system. Experiences with validation of EMT models during operation have been recently shown in [40], where such methodologies and procedures are still in the early stages of the industry.…”

“…An example of that could be changing parameters in case the grid gets weaker after a disturbance in the nearby grid. • Validation of Models and Improvement of Performance: Validation of EMT models and other types of models is of special interest during operation, as such models, once validated, can be used for plantlevel studies during operation with updated grid conditions provided by the TSO [40]. An example of a successful application of DT could be an automatic flow of information from different sites to validate models, where reports and self-analytics tools are implemented to identify possible mismatches.…”

“…The challenges intensify due to expanding testing scopes and vulnerability to onsite weather conditions, leading to protracted test campaigns. Additionally, limitations in current testing equipment and site constraints mean that some grid compliance features cannot be tested by manufacturers, introducing uncertainties regarding turbine behavior under specific grid conditions [8].…”

“…In this context, efforts are underway to improve and speed up the processes of testing, validation, and verification of grid compliance at both the WTG and WPP levels [8]- [17]. Recently released or in-progress standards, such as "IEC CD 61400-21-4: Wind turbine components and subsystems," "IEC TS 61400-21-5: Configuration, functional specification, and validation of hardware-in-the-loop test bench for wind power plants," "IEEE P2800.2: Recommended Practice for Test and Verification Procedures for Inverter-based Resources (IBRs) Interconnecting with Bulk Power System," among others, define crucial strategies for testing and validating WTG and WPPs concerning grid compliance and connection requirements.…”

EMT model validation of an offshore wind power plant with SGRE DD wind turbines under real power system events

“…testing, the industry is making progress in component and subsystem testing, as well as implementing Hardware/Softwarein-the-loop real-time solutions [12][13][14][15]. It is foreseeable that the current model validation procedures, which are already widely adopted, will continue to evolve, leading to further enhancements in accuracy and reliability.…”