How does Windmills Work?

Everyone has seen all the moves towards clean energy in the past few years. Things like solar and wind energy have become the new standard for clean energy as they don’t seem to have the bi-product problems of things such as electricity. While electric engines burn more cleanly than your standard combustion engine runs off gasoline or petrol they still require an input system that is typically one built out of a dirty fuel such as coal. Windmills can produce and store more energy than solar cells and tend to be more efficient overall.

When you see windmills towering over the town below, it is easy to wonder how they know which way to face in order to catch the wind properly. One of the key components in the built in pitch control system. This uses hydraulics in order to adjust the way the blades face and even change the position of the head. This allows the windmill to turn more rapidly creating more stored energy as it travels down the base of the system.

The center of the windmill is wired to capture all the energy created by the spinning top. It then travels down the wires to the base of the windmill where a battery sits to capture the energy. Other wires go to the general power source. This means you can both draw power immediately and store it for future use. This gives you more freedom with this version of clean energy. While you can store solar power it does not have the same conversion rate and you lose much of the energy in the storage process.

As for the direction of the windmills, that is up to the person who sets up the farm. Some windmills can use the pitch control system to move the entire direction of the head, while other windmills are stationary. The stationary ones can still move the blades to better catch the wind but the windmill itself always faces the exact same direction. For those close to the water, this is often a great choice as the wind tends to only come from one way.

Helping Increase Safety with Computerized Motors

Car manufacturers and assembly lines have long relied on servo motors in order to increase productivity and consistency on the line. Now, these same AC servo motors are helping to increase safety levels both for the employees of the plants and for those who are driving the vehicles. Technicians have realized the increased parameter options allows for more control over the finished product. This means less variation so that the pieces fit together in a way making them more stable than ever before and increasing the overall safety of the vehicle.

The AC servo motors that control the line help prevent overheating. This type of condition can cause fires, meltdowns and other dangerous situations for those who are monitoring the line. By using a mechanism that makes adjustments immediately, like a servo, the problem never has a chance to develop. It takes much less time to make a correction from the beginning than undoing a problem scenario has blown out of control. Think of it along the lines of laying a drop cloth down when you are painting or trying to clean up the paint off the ground after you are done. One is a simple clean up job and the other is a protracted process.

For the output of the product, because a servo motor can monitor things so closely there are fewer problems with the end product. When bolts and pieces do not meet up exactly, vibrations and other processes can cause things to wiggle loose. This factor often results in tires falling off, seat belts failing, pieces of the engine getting knocked out or other disastrous scenarios. By ensuring everything is exactly uniform, there is less chance of this type of problem. Basically it was the next logical step in the development of motorized vehicle development and the assembly line. The companies had maxed out what could be done with just humans and found a way to utilize the computerized systems in order to increase safety and productivity at the same time. Helping to make life safer is a great side benefit of computerized advances.

How BLDC Motors Work

Before using BLDC motors, understand its mechanism.

You will be able to find BLDC motors or brushless DC motors in industrial equipment, appliances and medical instruments as they provide various advantages as compared to others like it.

However, before usingthese motors particularly for blade pitch control, you must first have a complete understanding of its mechanism which consequently results to a fast review of the construction of a DC motor.

A BLDC motor is particular type of servo motors which basically relies on wire coils on rotors and frames of rigid motors which on the other hand places permanent magnets all over the rotor.

Electric current passing through the windings make some magnetic field which either repels it from the magnet or attracts a winding to the magnet. Brushes placed on stators and contacts placed on rotors choose various windings as power while the rotors turn.

In BLDC motors, the coils make up the motors’ outsides and the rotors provide permanent magnets. Once again, the repulsions and attractions of the coils and the permanent magnets make the rotors spin. However, in BLDC motors, commutations do no occur on spinning shafts.

Even though these motors are more expensive than other brush-DC motors, they provide benefits. Their exterior coils dissipate heat better than those on rotors. BLDC motors do not have commutators or brushes to tire out or need maintenance regularly, thus they can function unattended for a very long period of time. Lastly, these motors don’t produce electromagnetic interference or EMI from machine-driven commutators.

Rather than utilizing mechanical commutators, servo motors like BLDC use automated commutation in switching the coils to on or to off. This kind of commutation is classified into two – the sensorless or the sensor-based.

The sensor-based motors, Hall-effect sensors are placed inside the coils of the motor to sense the position of the permanent magnets of the rotors. Microcontrollers or MCU read the states of the sensors and utilize a particular algorithm to know which of the coils to power as well as when.

On the other hand, sensorless motors require MCUs to measure the back electromotive force orr EMF produced across coils by spinning rotors’ magnets. The back EMF or BEMF defines the magnets’ positions.

However, the sensorless method is faced with a challenge because controller as well should power coils consequently to make the motors turn. Thus, how can one separate pulse-width signals of modulation which drive coils BEMF signals?

The answer is quite simple. Program MCUs to filter high-frequency PWM signals out as well as measure BEMF near the time when PWM signals pass through zero Voltage. The BEMF depends on various factors like coil resistance, number of coil windings, rotor magnets strengths and many others.