Wind power grows rapidly

Wind turbines are usually installed in remote locations where there is no shelter.

It is understood that the development of wind turbines and electrical energy conversion equipment has made this green energy a mainstream.

The potential of wind energy Wind power has a wide potential for development throughout the southern United States, but many people still regard it as a local phenomenon in California. In fact, South Dakota has the greatest potential for wind energy, and Texas has the world's largest wind power plant. In the rankings of wind power potential in major states, California's rankings are actually quite late. The prairie region is the largest potential resource.

Wind power is showing a steady development momentum, although it currently only occupies a small part of the total electricity generation in the United States. In 2006, the total generation of wind power was 11,600 MW. However, according to estimates by the American Wind Association (AWEA), by 2007, there will be an increase of 3,000 MW, and it will show accelerated growth thereafter. (We can compare this figure with a conventional thermal power plant that generates 600MW to 800MW per year and a fuel cell power plant that produces no more than 150MW per year.)

At present, the biggest obstacle to the rapid development of wind power generation is the insufficient production of power generation equipment. Because the government is undecided about renewable energy policies, wind turbine manufacturers are reluctant to increase output. Randall Swisher, Executive Director of AWEA, said: “We have seen many new wind power plants being built and wind turbine generators have some exciting investments. But these are just the tip of the iceberg compared to our demand for wind energy. It is imperative that the U.S. government must issue a complete, long-term tax deduction system for energy production and a national renewable energy industry standard, so that we can make better use of renewable energy to generate electricity. Such a policy is bound to be urgently needed by the country. Renewable energy supply provides good support."

Location and Dimensions If a wind turbine is installed in the right place, it will be in operation 60% to 80% of the time. If the size of the wind turbine is also suitable, it will be at full capacity operation for at least 10% of the time. In this way, although a wind turbine anywhere may realize full-load power generation at a certain moment, a highly-utilized wind turbine will generate only 30% to 35% of the theoretical maximum power generation in one day. % of electricity.

If you want to calculate the level of power generation, take your fingers and count it. The constant power output of the power station is only 20% of the installed capacity. In other words, a wind power plant with an installed capacity of 10 MW actually produces 2 MW. Some people think that this level of power generation is very low, but it truly reflects the balance between cost, efficiency, and power generation. The wind turbine generator's blade size and power generation are most closely related to the wind conditions in a certain area and are the two main design parameters.

The output of the wind turbine is affected by the surrounding environment, and its output can only be optimized through the steering controller and the blade pitch adjuster. This poses special challenges for the unified control and power output of multiple wind turbine generators. A wind power station that supplies electric power to a region functions as a thermal power station or a nuclear power station. In addition, the power generation capacity of wind power plants should be able to meet different requirements, but it is not possible to switch off the fire on the specific operations like the thermal power station.

Complex control requirements Because the output of wind turbines is constantly changing, if a wind power station is to be integrated with a conventional power generation platform, a complex control system is bound to be required. The US Energy Monitoring Committee (FERC) is responsible for adjusting power generation equipment to ensure that wind turbines will work on existing platforms without conflict or affect the power supply in a certain area.

When wind power weakens, wind power generators slow down or stop running. At this time, the traditional control system will only set the wind turbine off-line. When the wind turbines are restarted, they must be manually returned to the online working state. In 2008, FERC will release a new control system, which will then give a solution to this type of low voltage or no voltage output. The control kit will keep the wind turbine on-line during this period, and automatically restore power when the output power increases.



Wind turbines of all sizes have the same basic structure, including adjustable struts, steering controls, acceleration gear boxes, and generator sets.

This month, Siemens plans to fully load new wind turbine blades at a plant in Fort Madison, Iowa, as an initiative to increase production of power generation equipment. The factory is producing blades for 35 new wind turbines with a capacity of 2.3 MW. The wind turbines will be installed at the Sweetwater wind power station near Abilence, Texas (TX). These blades have a single length of 48 feet and a single weight of 12 tons. The new platform plans to employ 400 employees.

Texas currently has more than 3,000 MW of wind power generation equipment, including three of the nation's five largest wind power stations, and is the nation's leader in the use of wind energy. In contrast, California's potential for wind power generation is not great, and the amount of electricity that can be utilized is only 2,376 MW. Wind power resources in Iowa, Minnesota, and Washington are among the top five countries in the United States.

In New York's Lackawanna area, there is a remarkable installation of wind power equipment. Eight new wind turbines rise from a field of scorched earth, originally a Bethlehem steel plant. This area was previously abandoned due to heavy industrial waste pollution and the disease was breeding. Wind power projects have brought new life to it. Today, wind turbines (daily) provide 20MW of electricity to the local community. There are similar projects in the northeast region. In these places, wind power plants have replaced the original mining or sewage treatment plants.

Operational considerations A significant drawback of wind turbine generators is that they operate normally only when the wind speed remains within a certain range. Therefore, their power generation capacity will change with weather conditions. Wind generators rely on wind sensors to sense the wind direction and wind speed to maintain good work efficiency. This sensor can be installed on a single wind turbine or in the middle of a wind farm. The wind turbine can be rotated centered on the support column (steering controller) to achieve the best windward angle, and can also achieve a specific rotation rate and torque by adjusting the tilt of the blades. These functions can be achieved by means of mechanical or hydraulic devices inside the wind turbine.

If a wind turbine stalls due to insufficient wind speed, once the wind speed reaches 9mph (4m/s) again, it will resume work through a set of startup procedures. The blades of the wind turbine are first turned to 0 degrees and then start turning. At this time, a speed adjustment period will adjust the speed of the blades to rotate the generator at a preset speed of approximately 900 rpm. Once this speed is reached, the control system shuts down the power converter and the generator, minimizing the problem of excessive output current.

The speed adjuster can balance the output of the speed and power of the leaf. Since the output power requirement of the generator is relatively constant, the control system compensates for changes in wind speed by finely adjusting the inclination of the blades. When the wind turbine is operating, this fine tuning is performed continuously to ensure that the blade torque is approximately constant.

If the wind turbine is to be stopped due to a mechanical fault or excessive wind speed, etc., a combination of reversed blade pitch and mechanical braking can be used. It is well known that if a massive object has a large momentum, it cannot stop moving in a short time. However, it takes only a few seconds for the wind turbine to brake in an emergency. When the wind speed is too fast, the blades can safely stay in a certain position.



Wind power plants can stabilize the voltage output when the load is constantly changing or high. They are equipped with a control device that can output energy statically even if the energy cannot be dynamically output, thereby keeping the system working. In this way, wind power plants have the ability to output a constant voltage while the surrounding environment is constantly changing. Power plants such as thermal power plants and nuclear power plants that use conventional technologies do not have such functions.

Wind power plants have this kind of function, and their role is not limited to simple power generation, but can be used as a key guarantee for power supply in a certain area. Victor Abater, GE Energy's vice president for renewable energy projects, said: “Wind generators and wind farms with static energy output and voltage control functions can provide a stable voltage for some sensitive systems. Expand this capability to none In the case of energy output, the benefits that traditional power generation equipment cannot bring can be obtained."

Nowadays, wind power stations are more and more remote, which poses a challenge to power transmission. An extreme example is that somewhere in the North Sea, a new offshore wind power station is being built 60 miles (100 km) from the German coastline. The installed capacity of this wind power station is 400MW. Once it is completed, it will be the largest offshore power station, and it is also the most remote one off the coast. This project will use ABB's HVDC (high-voltage direct current) optical transmission technology to enable tight control of equipment on land. Since wind turbine output is unpredictable, using this technology is critical. Peter Leupp, head of Power Systems at ABB, said: "Utilizing renewable energy to generate electricity will be severely challenged by the surrounding environment and distance."

The problem is not that wind power plants are considered by many to be intangible and it is impossible to achieve the desired results. The typical ideas are:

They are disguised. Although manufacturers do their best to increase power generation efficiency, some people still have this subjective mistake in their minds. Just imagine how could a device equivalent to a 30-floor building be disguised?

They make a lot of noise. Well, when the wind generator is running, it will make a slight buzz, but the size of the sound you can hear is related to which side of the machine you are standing on. In fact, the sound produced by wind generators is very light, and only people standing nearby can hear it.

They are birds and bat "killers." According to a survey by the National Academy of Sciences, birds are more likely to die from insecticides or to collide with cars and buildings than to die on wind turbines. Even the Audubon Society (a community of bird-lovers) has approved wind turbines.

There is such a case that reflects the problem: Hannover Park near the editorial office of Control Engineering, IL municipalities are considering a proposal to add a 1.6MW wind turbine on a junior high school campus. The electricity generated by wind turbines during their working years can save the school about $8,000,000 in funds. However, some people in the community are opposed to doing so. In their imagination, doing so is to build a 250-foot-tall monster in the community. This proposal may eventually be decided in court.

On the other hand, some people are welcome to wind power generators. Farmers can not only grow crops on the farmland under wind turbines, but also get a royalty of US$3,000 per kilowatt per year of electricity generation. This will inevitably bring double benefits to the rural community.