Cost-Effective Tower-Sway Condition Monitoring
for a 50 kW Wind Turbine Fleet
How Venn Design Solutions and Lillie Systems collaborated to develop a real-time tower displacement sensor for Orenda Energy's Skye™ Wind Turbine.
Adding Tower-Sway Measurement to an Existing Wind Turbine Fleet
Orenda Energy Solutions manufacture the Skye™ Wind Turbine, an innovative 50 kW turbine with a 4th-generation SCADA system for remote monitoring, control, and preventative maintenance. They wanted to add tower-sway measurement to the nacelle sensor array to further enhance safety and reliability.
Commercially available displacement sensors were either unable to operate at the required low frequency (1 Hz) or were too costly and complex to retrofit into the existing Skye™ architecture. Orenda Energy needed a cost-effective condition monitoring sensor that could measure tower-top displacement with sub-second response time and 1 mm resolution, installed across their fleet with minimal effort.
Wind turbine monitoring systems typically rely on vibration measurement using multi-axis accelerometers to detect abnormal operation. However, correlating sensor outputs with turbine signals such as wind speed or rotor speed in real time is a challenging task — but necessary to reduce false-positives that result in lost revenue from unnecessary turbine shutdowns.
Custom Tower-Sway Algorithm on an Intelligent Accelerometer
Lillie Systems identified a 3-axis ±2 g intelligent accelerometer with CAN bus and logic output that had the required measurement accuracy and internal processing power to be customised for the tower-sway application. Lillie Systems collaborated with Venn Design Solutions on the development and testing of a tower-sway algorithm that could be integrated directly into the sensor firmware.
The algorithm had to be compact enough to compute real-time tower-top displacement with a sub-second response time and 1 mm resolution — permitting immediate detection and shutdown in the event of abnormal operation. This is an example of edge processing applied to vibration analysis: the sensor itself handles the computation rather than requiring external DAQ hardware or post-capture analysis.
To develop the algorithm, a sensor and CAN bus datalogger were first installed into one of Orenda Energy's wind turbines to capture tower acceleration data. Using this high-speed data, Venn Design derived a reduced set of equations that, once implemented into the sensor's microcontroller, enabled it to convert acceleration measurements to tower-top displacement in real time.
Validated Correlation Between Wind Speed and Tower Sway
Once programmed with the new measurement capabilities, the sensor was connected into the existing Skye™ SCADA sensor array. Data was collected over a period of several months and used to identify a strong correlation between wind speed and tower sway under normal power production.
This analysis allows Orenda Energy to optimise fault detection limits for tower-sway conditions, minimising false-positives and the subsequent loss of power production due to unnecessary shutdowns.
The tower-sway sensor can now be added to any Skye™ Wind Turbine's SCADA sensor array, enabling remote monitoring of tower-top displacement to analyse long-term changes in characteristic performance, as well as real-time fault detection and safe shutdown in the event of abnormal tower motion.
Testimonials
“The staff in Venn Design Solutions were great to work with — they understood our requirements, and worked to meet them in the most cost-effective manner without making concessions.”
“As to the project, I also really enjoyed working on it. It is not so often we get the chance to collaborate on projects in this way and seeing some of the results, so hopefully there will be more of this to come in the future.”
Download the Complete Case Study
Read the full implementation details, measurement results, and RMS displacement vs. wind speed analysis in the original case study by Venn Design Solutions.
Download Case Study (PDF)
A2E-TRI — High-Performance, Cost-Effective Industrial Vibration Sensor
For modern vibration analysis and condition monitoring applications, the A2E-TRI is a high-performance, cost-effective solution. It provides triaxial acceleration data and onboard FFT analysis over PoE Ethernet — no external DAQ hardware required.
- ✓ Triaxial acceleration + onboard FFT per axis
- ✓ Single PoE cable for power and data
- ✓ NTP-timestamped for multi-sensor correlation
- ✓ Industrial IP67 aluminium housing