East Aurora, NY’s Dr. Sherif El-Henaoui is the Engineering Director of Moog Inc.
If you go to YouTube and search for “wind turbine explodes,” you’ll find footage that may be used in an ad touting the advantages of pitch-control devices. The technology does not receive much attention outside of those who design and manufacture these devices. However, it should. The key to maximising and safeguarding a multimillion-dollar wind turbine is a pitch-control system. Pitch controls, which are located in the hub of a wind turbine, allow the operator to alter the angle or pitch of the blades. Pitch controls account for around 3% of the cost of a wind turbine, according to the European Wind Energy Association. When the weather turns nasty, a simple investment, like an insurance policy, can make a significant impact. In 2007, Intercedent Asia experts assessed that 90 percent of new wind turbines included pitch controls. Although they are extremely universal, little is known about them. When the wind speed reaches 25 m/sec (50 mph), a wind turbine’s blades must be angled downward, lowering the load and bringing the wind turbine to a halt. Electric and hydraulic pitch controls are the most common types of pitch controls used for turning. Pitch control isn’t just for emergency scenarios. When the wind speeds up to around 12 to 13 m/sec (27 to 29 mph), which is when most turbines reach optimal performance, these systems will modify pitch (or turn) the blades a few degrees to set the turbine’s blades at an angle for best output.
“A pitch controlled wind turbine requires some creative engineering to ensure the rotor blades pitch exactly the amount required,” the Danish Wind Industry Association said recently. Because most wind turbine manufacturers (with the exception of Enercon and Vestas) outsource pitch control systems, design nuances may go unnoticed. It’s vital to realise that most wind turbine manufacturers are committed to using either hydraulic or electric pitch control technologies. Manufacturers of wind turbines rarely employ both types. “Their choice of pitch-control mechanism and design is totally a function of their choice of manufacturer,” according to Intercedent Asia research.
Nobody would recommend buying a wind turbine based just on the type of pitch control it offers. Understanding the differences between these systems, on the other hand, might help a consumer make a more informed purchase decision.
Those who are familiar with pitch controls have differing opinions on which system is better and why. There is no possibility of hydraulic fluid leaking with electric pitch control. As a result, there are no environmental concerns with these systems, as there would be with a system that relied on oil under high pressure. There is also less usage or waste of energy. Because hydraulic pitch controls require a pump to be active at all times, electric pitch controls utilise less energy. That pump uses energy to keep the system’s oil at high pressure and to be ready to turn the rotor blades at a moment’s notice.
Failsafe batteries or capacitors, on the other hand, are a weakness in electric pitch control systems. The life of a pitch control battery is two to three years. It is a major undertaking to replace it once its useful life has expired. Consider scaling a 2MW turbine tower to replace a battery in the prop’s hub.
“Supporters of hydraulic and electric systems always claim advantages for each type of technology,” Intercedent Asia researcher Peter Baldwin stated. ” On one hand, there is a strong case for electric vehicles due to environmental concerns. Electricity also has the advantage of being preferable for colder areas because hydraulic fluid loses viscosity as the temperature drops. Hydraulic systems, on the other hand, have a distinct advantage in terms of speed and reliability.
“With hydraulics, maintenance and diagnostics are considered to be easier because fewer technical components are utilised,” Baldwin continues.
In addition, despite rising oil prices, the cost of hydraulic fluid in pitch controls isn’t substantial because it’s a closed system that recycles almost all of the oil it consumes.
However, upcoming developments may provide wind-turbine manufacturers a third option: hybrid control. The blades of the wind turbine are spun electrically with a hybrid control, while failsafe elements, which prevent blade damage, are run hydraulically. Proponents of the hybrid concept claim that the risk of oil leakage would be reduced because the pitch control would be mostly powered by electricity. They claim that energy prices would be reduced as well. Advocates note out that because a hybrid pitch control relies on a hydraulic system for failsafe power, buyers won’t have to worry about a failsafe battery losing charge after a few years.
Pitch controls, regardless of type, play a key part in protecting and profiting on a wind turbine investment, in addition to assisting in the efficient production of power from the wind. Buyers owe it to themselves to grasp this often overlooked technology and utilise that knowledge when purchasing a wind turbine, whether the design team chooses electric, hydraulic, or hybrid.
Moog, Inc.’s European marketing manager is Dr. Sherif El-Henaoui. He also oversees initiatives for key industries like plastics machinery as well as emerging markets like wind energy and services.
Is it true that a wind turbine is a hydraulic system?
Pitch adjustment, yaw and rotor braking, cooling and lubrication, and power transfer are the most significant hydraulic operations of wind turbines. The rotation of blades weighing tonnes must be controlled in wind turbines. The blades will rotate faster under high wind speeds, causing damage to the turbine.
Is a wind turbine pneumatic or hydraulic?
Hydraulic systems are critical for wind energy generating. Wind turbines rely on hydraulics to generate the required air density for energy generation. Hydraulics are applicable to all types of wind technology, making them a versatile solution for wind energy plant power needs.
Modern wind turbines use hydraulic systems for brake control, blade rotation regulation/setting, and spinning the blades to increase wind speed. A hydraulic powertrain with a rotor and blades is created via a hydraulic system consisting of hydraulic hoses and hose assemblies. The rotor blades of small turbines are usually fixed, whereas bigger turbines require blades with a pitch. The precise pitch of the turbine’s blades is ensured by a hydraulic reservoir, motor, pump, and other equipment. Hydraulic pitch control and a hydraulic battery can operate without the use of external power, saving energy. This results in a faster stopping time and a wider working temperature range.
Hydraulic systems are becoming more and more common in wind technologies across the industry as a more lightweight, more powerful, and less expensive alternative to electricity.
Are wind turbines able to change their pitch?
The wind turbine’s aerodynamic power can be reduced via variable pitch control. By modifying the pitch angle of the wind turbine, the aerodynamic power produced by the wind turbine may be regulated.
In a wind turbine, how much hydraulic fluid is there?
At the moment, the average wind farm has 150 turbines. Each wind turbine requires 80 gallons of oil for lubrication, and this isn’t vegetable oil; this is a PAO synthetic oil based on crude… 12,000 gallons. Once a year, its oil must be replenished.
To power a city the size of New York, it is estimated that about 3,800 turbines would be required… For just one city, that’s 304,000 gallons of refined oil.
Now you must compute the total annual oil use from “clean” energy in every city across the country, large and small.
Not to add that the huge machinery required to construct these wind farms runs on gasoline. As well as the tools needed for setup, service, maintenance, and eventual removal.
Each turbine has a footprint of 1.5 acres, so a wind farm with 150 turbines would require 225 acres; to power a metropolis the size of NYC, 57,000 acres would be required; and who knows how much land would be required to power the entire United States. Because trees form a barrier and turbulence that interferes with the 20mph sustained wind velocity required for the turbine to work correctly, all of this area would have to be cleared (also keep in mind that not all states are suitable for such sustained winds). Cutting down all those trees is going to irritate a lot of tree-huggers who care about the environment.
A modern, high-quality, highly efficient wind turbine has a 20-year lifespan.
They can’t be reused, reconditioned, reduced, repurposed, or recycled on a budget, so guess what? They’re heading to specialised dumps.
What’s more, guess what else…? They’re already running out of space in these dedicated landfills for blades that have outlived their usefulness. Seriously! The blades range in length from 120 to over 200 feet, and each turbine has three of them. And this is despite the fact that wind energy currently serves only 7% of the country. Imagine if the remaining 93 percent of the country was connected to the wind grid… in 20 years, you’d have all those useless blades with nowhere to put them… Then another 20 years, and another 20 years, and so on.
I almost forgot to mention the 500,000 birds killed each year by wind turbine blade collisions, the most of which are endangered hawks, falcons, owls, geese, ducks, and eagles.
Smaller birds appear to be more agile, able to dart and dodge out of the way of the spinning blades, but larger flying birds appear to be less fortunate.
What applications do we have for hydraulics?
Hydraulics is the lifeblood of our company. We know everything there is to know about them, but we mostly see them in heavy machinery, such as rail calibration, maintenance, and installation. Hydraulics are also used in fastening, such as with hydraulic torque wrenches.
But isn’t it used for more than just lifting trains and tightening bolts? In the office, we wracked our brains for examples of where hydraulics are applied in everyday life. Here’s our list; can you think of any more?
- Pumps for gasoline. Hydraulics are used to transport the fuel from the storage tank to the vehicle.
- Cars. The brakes on all four wheels of a car are controlled by a hydraulic brake circuit.
- Vehicle maintenance and repair. A hydraulic system is what allows a very heavy car to be raised and lowered while it is being serviced.
- Dishwashers. Hydraulics are used to boost water pressure for better cleaning. Hydraulic-assisted dishwashers are typically generally quieter.
- Machines used in construction. Hydraulics are used to lift and lower objects by cranes, forklifts, jacks, pumps, and fall arrest safety belts.
- Airplanes. Their control panels are operated by hydraulic mechanisms.
- Rides at amusement parks. Attractions like the Ferris Wheel rely on hydraulic machines to provide and control motion.
- Theatrical presentations are those that are performed in front of an audience. Stages can be raised higher and returned to their original position using hydraulic force.
- Elevators. A hydraulic mechanism is used in some elevators to power the elevator car’s movement and to stop it when necessary.
- Snowplows. The plough may move up and down as well as side to side thanks to hydraulic mechanisms.
- Bakeries. Hydraulics are used to mass-produce breads and pastries, which allows them to be raised, flipped over, and pushed along conveyor belts for packaging.
- Chairs for barbers. The barber walks on a pump that employs a hydraulic lift mechanism to modify the chair’s height.
- Chairs for the workplace. As you adjust the chair’s matching levers, it can rise or fall, lean backwards or forwards thanks to hydraulics.
The list goes on since hydraulic equipment also power firms that build and fit everything from automotive parts and accessories to doors, fences, and hoses.
Consider what might have happened if hydraulics hadn’t been invented. Anyone want to go back to doing manual labour with wedges, inclined planes, and pulleys?
What are the average working pressures for the hydraulic pitch system of a wind turbine?
HAWE. HAWE Hydraulics’ small and light KA power units fit snugly into wind turbine nacelles and generate pressures up to 10,000 psi.
What is wind turbine pitch control?
Pitch controls rotate the blades of wind turbines so that they employ the optimum fraction of available wind energy to produce the most electricity, while also ensuring that the turbine does not exceed its maximum rotational speed.
In a wind turbine, what is the pitch angle?
The angle at which a propeller, rotor, or turbine blade is set with respect to the plane of rotation (the angle being measured between this plane and a straight line from one edge of the blade to the other in a direction perpendicular to its radius).