Wind testing and inspection services help verify the safety, reliability, performance and compliance of wind, turbines and components. UL offers one-stop safety and performance testing services for wind turbines and their components based on international and national standards and regulations (IEC 61400 series, MEASNET, FGW). We operate world-class wind testing sites around the globe and perform inspections of operating equipment in the field. They provide excellent environmental conditions and on-site technical support that deliver quick, reliable results and reduced time-to-market.

Our services cover many areas in project development for planning and engineering, construction and commissioning, and operations and maintenance. We offer measurement services and instrumentation solutions to assess the power quality characteristics and grid compliance of wind turbines and wind farms, the acoustic noise emission of wind turbines, and the power performance and mechanical loads of wind turbines and wind turbine components. We also provide sensor calibration services, provisioning of wind energy measurement equipment, and training courses for industry professionals.


Validation & Type Testing

Validation testing is the process in the overall product development that helps verify that the wind turbine (component) is implemented in reality as designed. Type testing in the context of wind turbine type certification, however, helps verifying that the wind turbine (component) is in compliance with relevant and defined standards and rules.

UL provides field and laboratory testing to acquire the data needed to verify wind turbine function, safety, structural integrity, power performance, power quality, and acoustic noise emission characteristics. Besides worldwide testing activities with customer prototypes, UL operates two wind turbine test facilities offering favorable year round wind conditions for the testing of small and large wind turbines for extended periods.

 

Mechanical Loads

When developing new wind turbines, extensive measurements of the mechanical loads acting on the prototypes during operation are indispensable. The results of these load measurements carried out by UL are used in the design validation and certification of wind turbine prototypes. UL offers load assessments according to IEC 61400-13 or any customer specific scope on wind turbines and their components.

 

Power Performance

The measurement of wind turbine power curves is one of the key activities within UL services. The power curve summarizes a lot of the efforts that went into the design of a wind turbine and as such the power curve report is an integral part of every type testing campaign. Next to the classic setting of measuring a power curve using met tower based cup anemometry, UL is active in the development of the methodology utilizing ground based lidars to operate with the new wind speed definition of rotor equivalent wind speed.

UL offers nacelle based measurement approaches using data from cup anemometers, lidars or spinner anemometry. These are interesting alternatives in offshore environments as well as for turbines with large hub heights and when it comes to detecting yaw misalignment.

UL tests to the following standards:

  • IEC 61400-12-1
  • IEC 61400-12-2
  • Measnet Power Performance Measurement Procedure Version 5
  • FGW Technische Richtlinie 2, Rev 6 and FGW Technische Richtlinie 5, Rev 5
  • IEA wind, 15. Ground-based vertically profiling remote sensing for wind resource assessment
  • DTU E-0019, Procedure for wind turbine power performance measurement with a two-beam nacelle lidar

 

Electrical Characteristics

In the field of grid integration UL carries out measurements and evaluations to determine the electrical characteristics and grid compatibility of wind turbines. The measurements are required for planning grid connections and verifying applicable limits, but they also allow an exact analysis of the electrical behavior of the generation units and systems, which is important for their design, development and optimization. In this connection, UL also carries out calculations of required grid capacities as well as power quality and background interference measurements.

UL tests to the following standards:

  • Technische Richtlinien für Erzeugungseinheiten und -anlagen, Teil 3 (TR3): Bestimmung der elektrischen Eigenschaften von Erzeugungseinheiten und -anlagen, Speicher sowie für deren Komponenten am Mittel-, Hoch- und Höchstspannungsnetz; Rev. 25; Stand: 01.09.2018; Herausgeber: Fördergesellschaft Windenergie und andere Dezentrale Energien (FGW e.V.)
  • IEC 61400-21: Wind turbines – Part 21: Measurement and assessment of power quality characteristics of grid connected wind turbines; Edition 2.0 2008-08.

 

Low Voltage Ride Though (LVRT) Testing

Before any generating plant can be connected to the grid, the system operator normally requires a certificate. This in turn requires the measurement of electrical characteristics and also verification of the plant’s Low Voltage Ride Through (LVRT) capability. UL offers LVRT testing and measuring services to determine the electrical characteristics and grid compatibility of wind turbines.

UL tests to the following standards:

  • Technische Richtlinien für Erzeugungseinheiten und -anlagen, Teil 3 (TR3): Bestimmung der Elektrischen Eigenschaften von Erzeugungseinheiten und -anlagen am Mittel-, Hoch- und Höchstspannungsnetz; Rev. 23; Stand: 01.05.2013; Herausgeber: Fördergesellschaft Windenergie und andere Erneuerbare Energien (FGW e.V.)
  • IEC 61400-21: Wind turbines – Part 21: Measurement and assessment of power quality characteristics of grid connected wind turbines; Edition 2.0 2008-08.
  • Particular Grid Code requirements which may vary from country to country.