Wind turbines are prone to vibration problems. According to research data, about 40% of all wind turbines have high vibrations which exceed vibration limits. These vibrations cause structural loads, increased wear, adverse start-up conditions, and often vibration-related shutdowns. Most vibration problems are detected too late. Condition monitoring systems—often used to measure vibration levels—are not always able to interpret the measured signals correctly. Downtime can occur more often as wind turbines age.
Rotating parts of wind turbines are balanced after production. Each blade is profiled and balanced to ensure it meets balancing tolerances. Balancing tolerance requirements are specified according to ISO 1940-1:2003 Standard for Rigid Rotors. There are two types of imbalance in wind turbine blades: Mass and aerodynamic imbalances. Mass imbalance is caused by voids and inclusions that happen during manufacturing, and aerodynamic imbalance is caused by shrinkage and inconsistency in the mold profile that cause blade angles variations and profile geometry deviations. Once the blades are profiled and balanced, they are installed on a blade hub and the system is inspected for possible parts mismatch that could add further imbalance.
The generator armature is also balanced after production. Manufacturing imperfections in laminates and coil layouts generate imbalance in the system. Armatures are balanced on a balancing machine, which displays the amount and location of imbalance. An operator would remove the laminate materials or add weights to the armature; the process is repeated until it meets balancing tolerances. The process is not only time consuming and expensive, but the generator can also lose power output.
Traditional balancing methods of removing materials or adding weights do not compensate for additional imbalances that occur in field due to icing, corrosion, damage to the rotor blade, debris deposits, and many more. When the wind turbine is overhauled, the balancing process would have to be repeated. The method does not solve the vibration problems at the source, but only acts as a bandaid.
XYO is a patented mechanical balancing technology that significantly reduces or eliminates vibration in rotating equipment. XYO could automatically and continuously balance rotating parts of wind turbines so that they produce less vibration and operate more efficiently. XYO can be installed on or built into rotating parts of the wind turbine, such as the blade hub cone and rotor shaft. XYO’s unique feature is its ability to continuously adjust to changing imbalances in the system; it is a mechanical system that is cost-effective to implement and does not require any electronic control systems to operate.
XYO provides a solution for high maintenance and inefficient wind turbines, and benefits include:
- Improved energy efficiency
- Reduced vibration
- Greater power output
- Lower maintenance costs
- Reduced noise emission
- Less mechanical wear.
Implementing XYO would improve balancing precision and energy efficiency. Downtime could be minimized and the wind turbine can spin faster, thus increasing energy output.
Research on implementing XYO in wind turbine systems is currently underway. The investigation includes the effect of different imbalances to the power output of the generator and a feasibility study of applying the XYO Technology to wind turbines. Modeling and simulation would help us shorten the prototyping stage. A prototype will be built to confirm the simulation results. Our goal is to quantify the value and benefits of implementing the XYO Technology in wind turbines.
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