Right now most conductivity tests for wind turbine (WTG) blades are performed via Rope Access: only the blade is measured, from the root of the blade to the receptors. When deploying Aerones robotic technology to do LPS measurements we use long wires to complete a full circuit test in order to check whether, in case of a lightning strike, the charge will actually be properly grounded.
Performing the full circuit test also allows us to find where the WTG LPS system has missing connections; i.e., between the hub and the nacelle, the nacelle and the tower, etc.
If the wind turbine has spark gaps, rolling lightning conductors, or carbon brushes, we create a shunt, i.e., a bridge, between these gaps.
Here's how our LPS inspection reports look like. We show the exact measurement of resistance for each receptor.
From our experience, there are many cases with no readings for the entire WTG blade. In such cases, we can do troubleshooting to locate the cause of the problem within the LPS.
The first type of troubleshooting is to measure from the tip of the WTG blade to each receptor: we put one end of the Megger probe on the tip of the blade (the equipment we use we call a "sock") whereas the other end of the probe the robot will bring to each receptor. There is a special kind of a "sock" for metallic blade tips as well as for blade tips with a receptor. In both cases, we can measure from tip to each of the receptors.
The other type of troubleshooting is to do the measurements from the WTG blade root to each receptor. We find that in most cases, the problem is somewhere between the last receptor and the root of the blade. The most common situation would be a broken wire or some issue within the lighting register box.
For the kind of cases where creepage problems, broken wires, or gaps exist, which usually form over time due to changes in temperature, different material expansion coefficients, mechanical damage, oxidation, or other reasons, here at Aerones, we have developed special equipment to test continuity within the LPS where classical measuring methods do not work: normally, low resistance Ohm-meters, with the measurement range up to 2 kΩ, are used. If there's a spark gap in the LPS, the resistance can go above a 100 kΩ (and even MΩ) range.
The High Voltage Gap Tester generates shots of high voltage pulses to overcome the dielectric strength of the material between the conductors. This way we have the opportunity to adjust the output voltage by changing the distance between etalon electrodes, and by doing so we can determine how big the gap is within the LPS.
Here is an example, how we measure how big the gap is within the LPS.
We create the spark, which will always travel through the shortest gap. If, for example, in the WTG blade the gap between two wires of the conductor will be 1 cm and in our test equipment 2 cm, the spark will jump through the wire in the blade.
If the gap in the blade is, for example, 2 cm and on the ground 1.9 cm, the spark will jump through the gap into the ground.
By performing this kind of test, it is not possible to damage anything within the WTG. For comparison: the voltage level for lightning strikes varies within the range of 10 to 120 MV. We use pulses of 100 kV: hundreds of times smaller than the lightning strike.
Throughout this season, we have done the Lightning Protection System (LPS) inspections already for more than 5,000 receptors and set a pace of conducting LPS inspections for 3 to 4 wind turbines per day using only one Aerones service unit. This is an unprecedented speed of LPS inspections for the industry.
Automation in WTG leading-edge repair is now a reality. Aerones is taking a step-by-step market approach with the introduction of robotic LE repair services. This low wind season Aerones are teaming up with rope access technicians to conduct LE repair campaigns.
With the Aerones robotic system's LE preparation tools, we are able to do the heavy lifting of the LE sanding and decontamination, boosting the Rope Access Technician (RAT) team’s productivity by 30-40%. This allows the RAT team to focus only on filler application and final painting.
Aerones in consultation with the world's leading OEMs and blade repair service providers are now developing a fully automated LE repair solution and it will be made available in the soon future.
We are happy to announce that Aerones technology for wind turbine services is recognized
by the biggest wind turbine OEMs in the world.
For the last month we are conducting a pilot project together with Vestas for
the Lightning Protection System (LPS) tests using the Aerones Robotic Technology.
Our team is able to demonstrate unprecedented speed for LPS tests by servicing
on average 3 turbines per day using only one Aerones unit. In addition to fast-paced
services, we are able to provide the safest solution on the market – using
our robotic technology there is no need for technicians to hang in the ropes
on the blade - the robot is doing it instead.
Currently, our units are operating in Europe and USA. If you are interested in scheduling demonstrations or LPS tests, feel
free to call
+371 2809 0999
or write to
sales@aerones.com
Latvian drone startup Aerones has announced a $1.6 million seed investment and a whole new direction for the business: the funding will go toward a ground-based robotics system for wind turbine maintenance and inspection. The round was backed by Change Ventures, YCombinator and the Sensum Group, as well as angels Paul Buchheit and Janis Krums.
The new ground-based system is based on a patented technology, wherein a computerised winch allows a robotic arm to perform many tasks, such as close-up photography, laser scanning, lightning conductivity tests, blade cleaning, and coating protective materials.
“Technicians who would otherwise hang hundreds of meters in the air manually working on each turbine blade, where safety concerns and weather limit operations, can now operate these inspection and maintenance services from the safety of a van, with controls that are as easy to use as a kid’s gaming console,” says Janis Putrams, the startup’s CEO.
Based in Riga, the Baltic business previously developed heavy-lift industrial drones, participating in YCombinator W18, finishing in the top three of Slush’s 100 Pitch Competition in 2018, and securing €2.7 million in funding just last August.
“In Aerones we see a company that has spent the last two years understanding in detail the challenges faced by the wind energy industry,” says Andris K. Berzins, managing partner of Change Ventures. “Using these insights, they re-invented their initial drone technology to tailor a robot & winch system that is so elegant that it will take the industry by storm.”
Some Aerones robots are already deployed in the US and Europe after completing successful pilots last year. The fresh funding will help increase commercial adoption and expand the company into the US.
The whole inspection is done in under 2 hours, including the set up and de-rigging.
We have achieved another great milestone in our technology advancement – an automated solution for Leading Edge Repair. We successfully conducted the first LE repair on-site using the Aerones robotic technology. Here is a video of how we repair the Leading Edge in less than 2 hours: https://youtu.be/M9KUZptq2SM
The automated LE repair consists of 5 steps:
No | Step | Description | Time necessary |
1. | Laser scan | Scan the blade before the repair and generate a 3D model of the blade in 12 μm (micrometer) precision to assess the blade condition and adjust the tools. | 15min |
2. | Grinding and sanding | Remove the damaged/eroded layer to allow for application of a new layer of filler. | 10-20min |
3. | Decontamination | Clean up the blade and prepare it for filler application to provide maximal durability of the material applied later. | 10-20min |
4. | Filler application and profiling | Apply an exact amount of the filler material on the blade and profile it in a high-precision. | 10-20min |
5. | Laser scan | Scan the blade after the repair to validate the result and guarantee the highest quality. | 15min |
- | Changing the robotic arms | After each of the steps it is necessary to change the robotic arms. Each of the robotic arms perform different task | 5min x 4 |
- | Total time | Time necessary to perform the whole process for one blade | 1.5h - 2h |
Besides LE Repair, the Aerones robotic blade care systems can perform:
Despite the current challenging situation around the world, Aerones crew keeps on working on wind turbine maintenance service projects in the USA and Europe while taking precautions and maintaining social distancing. It is a challenging time we all face, but thanks to unique Aerones technology characteristics, it is possible to continue the wind turbine maintenance services.
As for the latest project, we conducted a Lightning Protection System (LPS) conductivity test for 100 turbines in Texas, USA (See a video: https://bit.ly/2WUxJAc). In a team of two Aerones technicians and one Aerones service unit, on average we inspected ~3-4 WTGs a day, which is an unprecedented speed for such services in the industry. In terms of wind turbine downtime, this means only ~2h of downtime per turbine, including the set-up of the system.
Besides of conductivity test, Aerones also provide other automated wind turbine services using our robotized technology. The available services include:
Please receive an overview of the LPS conductivity test services HERE:
There you will find a video of how the process is conducted using Aerones robotic technology.
Aerones has started operating in the USA, Texas, where we are performing wind turbine lightning protection system conductivity tests using our automatized robotic system for turbines being at risk of possible lightning strikes. A short video of how are we doing can be seen here: Aerones In Texas.
So far we have done conductivity tests on dozens of turbines and our experience shows that most of the turbines are exposed to a significant risk of lightning strikes, as the lightning protection conductivity system is damaged or not working properly. An issued lightning protection system can lead to a total breakdown of the generators and blades, leading to unexpected costs of even more than $300,000. To be on the safe side and avoid such damages, contact us and order fast (3h per turbine), efficient and robotized services for your wind turbine lightning protection system test.
Besides of lightning protection system test, Aerones robotic system can provide the following services:
The technology offers efficient and unmanned operations with uncompromising health and safety concerns in mind. The whole Aerones robotic system can be assembled and disassembled in an hour, thus significantly minimizing the wind turbine downtime. Please see more in our brochure:
We have developed a new solution for automated Leading Edge preparation for the following repair or protective shell application. More efficient and much faster service than it was available until now!
We're committed to finding innovative ways to improve wind turbine maintenance. To increase labor safety and reduce costs and time spent, Aerones invented the world's first WTG maintenance robotic system. The technology offer efficient and unmanned operations with uncompromised health and safety concerns in mind. The whole Aerones robotic system can be assembled and disassembled in an hour, thus significantly minimizing the wind turbine downtime.
Using Aerones robotic system, you get everything from a single source:
Aerones were contracted to perform Vestas V80 wind turbine blade grease and accumulated dust removal using automated rope robotic system. Additionally, all lightning receptor conductivity tests were conducted to ascertain the lightning protection system proper functioning. Several malfunctioning receptors were found and reported to the client for remedial works.
To ascertain cleaning quality control, all of the turbine blades were photographed before and after the cleaning took place.
It took Aerones team 18 hours to complete the full cleaning process, close visual inspection and LPS tests (10 receptors per blade). All of the inspection findings were reported to the client. Data stored on Aerones secure servers for convenient access. PDF format reports were also made available to the client.
