Wind Turbine Surge Protection

Strikesorb is the premier offering from Raycap for surge and lightning protection for wind power systems. To accommodate the need for green energy and next generation power technology, more wind farms continue to be built and current wind farms are being expanded. As this trend continues, both turbine manufacturers and wind farm owners/operators are becoming increasingly aware of the costs associated with damage to these systems from the environment. The costs that occurs when a turbine sustains a lightning strike comes in two forms: the monetary costs associated with replacement of machinery caused by physical damage and the costs associated with the system being taken offline and becoming incapable of producing power. Electrical systems inside of wind turbines are at risk and face continual challenges based on the open landscapes that often surround them because they are generally the tallest structures in an often times exposed area.

They are continuously at the mercy of harsh weather conditions, and the likelihood of a turbine being struck by lightning several times throughout its lifespan is very real. The costs of equipment replacement and repair must be factored into the business plan of any wind farm operator because direct and indirect lightning strike damage is created by intense electromagnetic fields that create transient overvoltages. These overvoltages are then passed through the electrical system directly to sensitive electronic equipment within the turbine itself. As the surges propagate throughout the system they produce both immediate and latent damage to circuitry and computerized equipment including components inside wind turbine generators, transformers, power converters, control electronics, communication and SCADA systems. Direct and immediate damage may be obvious, but latent damage that occurs as a result of multiple strikes or repeated exposure to surges can occur to key power components within a wind turbine, and many times this damage will not be covered by manufacturer’s warranties.

Offline costs are another major factor that must be figured into any business plan associated with a wind farm. These costs come when a turbine is disabled and must be worked on by a service team, or have components replaced which involves both purchase, transport and installation costs. The revenues that can be lost due to a single lightning strike can be significant, and the latent damage that is produced over time adds to that total. Raycap’s Strikesorb products significantly reduce these associated costs because they do not need to be reset or replaced , even after multiple instances of lightning strike.
Before Strikesorb, the major issue with SPDs designed for wind turbine installations had been their design. For many years the only surge protection technology available to wind turbine manufacturers were conventional Metal Oxide Varistors (MOVs) inside plastic housings with DIN rail mountings. While there are places that these types of SPDs are entirely suited, they are typically not the right solution for wind turbine protection. The direct or indirect strikes to wind turbines will produce surge levels many times far exceeding the capacities of these devices, and the possibility of multiple strikes and surges in a short period of time is high. Even the most mundane and routine instances of control system failures which resulted in triggers within the SPD require resetting or replacement in conventional SPD designs. The downtimes in between operations restoration by service crews was a major source of revenue loss due to production outage. Raycap’s state-of-the-art product, Strikesorb® requires no maintenance or resetting after triggering. This, combined with the fact that it is housed in a more robust cylindrical aluminum housing, provides lifetime protection to wind turbine systems. This patented design offers lifetime protection against surges as it resolves ageing issues that seriously impact the performance of the more traditional DIN rail mounted SPD technologies. Strikesorb SPDs can sustain multiple and successive lightning strikes and power surges without requiring maintenance.

Strikesorb is classified as a Class I or Class II SPD according to the international IEC 61643-11 standard for surge protection devices, and all versions are fully compliant to the UL1449 4th Edition Safety Standard.