# Validation of Simplified Load Equations Through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower

## Abstract

As part of an ongoing effort to improve the modeling and prediction of small wind turbine dynamics, the National Renewable Energy Laboratory (NREL) tested a small horizontal-axis wind turbine in the field at the National Wind Technology Center. The test turbine was a 2.1-kW downwind machine mounted on an 18-m multi-section fiberglass composite tower. The tower was instrumented and monitored for approximately 6 months. The collected data were analyzed to assess the turbine and tower loads and further validate the simplified loads equations from the International Electrotechnical Commission (IEC) 61400-2 design standards. Field-measured loads were also compared to the output of an aeroelastic model of the turbine. In particular, we compared fatigue loads as measured in the field, predicted by the aeroelastic model, and calculated using the simplified design equations. Ultimate loads at the tower base were assessed using both the simplified design equations and the aeroelastic model output. The simplified design equations in IEC 61400-2 do not accurately model fatigue loads and a discussion about the simplified design equations is discussed.

- Authors:

- National Renewable Energy Laboratory (NREL), Golden, CO (United States)

- Publication Date:

- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)

- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Wind and Water Technologies Office (EE-4W)

- Contributing Org.:
- AnemErgonics, LLC, Arvada, CO (United States)

- OSTI Identifier:
- 1435409

- Report Number(s):
- NREL/TP-5000-67562

- DOE Contract Number:
- AC36-08GO28308

- Resource Type:
- Technical Report

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 17 WIND ENERGY; SWT; fatigue; simplified loads approach; IEC 61400-2; modeling; FAST; design load case; damage equivalent loads

### Citation Formats

```
Dana, Scott, Damiani, Rick R., and Van Dam, Jeroen J..
```*Validation of Simplified Load Equations Through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower*. United States: N. p., 2018.
Web. doi:10.2172/1435409.

```
Dana, Scott, Damiani, Rick R., & Van Dam, Jeroen J..
```*Validation of Simplified Load Equations Through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower*. United States. doi:10.2172/1435409.

```
Dana, Scott, Damiani, Rick R., and Van Dam, Jeroen J.. Tue .
"Validation of Simplified Load Equations Through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower". United States.
doi:10.2172/1435409. https://www.osti.gov/servlets/purl/1435409.
```

```
@article{osti_1435409,
```

title = {Validation of Simplified Load Equations Through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower},

author = {Dana, Scott and Damiani, Rick R. and Van Dam, Jeroen J.},

abstractNote = {As part of an ongoing effort to improve the modeling and prediction of small wind turbine dynamics, the National Renewable Energy Laboratory (NREL) tested a small horizontal-axis wind turbine in the field at the National Wind Technology Center. The test turbine was a 2.1-kW downwind machine mounted on an 18-m multi-section fiberglass composite tower. The tower was instrumented and monitored for approximately 6 months. The collected data were analyzed to assess the turbine and tower loads and further validate the simplified loads equations from the International Electrotechnical Commission (IEC) 61400-2 design standards. Field-measured loads were also compared to the output of an aeroelastic model of the turbine. In particular, we compared fatigue loads as measured in the field, predicted by the aeroelastic model, and calculated using the simplified design equations. Ultimate loads at the tower base were assessed using both the simplified design equations and the aeroelastic model output. The simplified design equations in IEC 61400-2 do not accurately model fatigue loads and a discussion about the simplified design equations is discussed.},

doi = {10.2172/1435409},

journal = {},

number = ,

volume = ,

place = {United States},

year = {Tue Apr 24 00:00:00 EDT 2018},

month = {Tue Apr 24 00:00:00 EDT 2018}

}