what is the principle of generator
Answers
Answer:
Both of these generators produce electrical power based on the principle of Faraday's law of electromagnetic induction. This law states that when a conductor moves in a magnetic field it cuts magnetic lines of force, which induces an electromagnetic force (EMF) in the conductor
Explanation:
Two studies published today in Science show different ways that beefing up the process by which plants create energy — called carbon fixation, or photosynthesis — could lead to a better future. In one, scientists decided that the entire process of carbon fixation was too slow and created a new, and faster, cycle. In the other, researchers engineered plants so they could absorb more sunlight. These enhanced plants grew up to 20 percent bigger, which is a big deal for food supply.
SCIENTISTS MADE A COMPLETELY NEW PHOTOSYNTHESIS SYSTEM
Plants are some of our best allies in the climate change fight. Global warming happens because of too much carbon dioxide in the atmosphere, and we add CO2 through activities like burning fossil fuels for energy. Because plants absorb carbon dioxide, they suck up some of the extra CO2 in the air and can even buy us extra time on global warming. But photosynthesis isn’t as efficient as it could be, so scientists are teaching plants how to do their jobs better to make our own lives easier. There may be other benefits besides locking down carbon: better plant growth means more food for a booming human population.
To make carbon fixation happen, organisms use molecules called enzymes. But the main enzyme doesn’t work very fast, says Tobias Erb, a synthetic biologist at the Max Planck Institute for Terrestrial Microbiology who is a co-author of one of the Science papers.
His team decided that they could design a way to make the process happen more quickly. They spent years figuring out which combination of enzymes would work together to get the job done. In the end, a combination of 17 enzymes fit the bill. These enzymes come from nine organisms (including e. coli bacteria and the human liver). Three of the enzymes were designed using a computer; that’s how delicate the balance is. When these enzymes are combined together, they can turn carbon dioxide into organic compounds better than plants and other organisms currently do. A dc generator is an electrical machine which converts mechanical energy into direct current electricity. This energy conversion is based on the principle of production of dynamically induced emf. This article outlines basic construction and working of a DC generator.
Construction Of A DC Machine:
Note: A DC generator can be used as a DC motor without any constructional changes and vice versa is also possible. Thus, a DC generator or a DC motor can be broadly termed as a DC machine. These basic constructional details are also valid for the construction of a DC motor. Hence, let's call this point as construction of a DC machine instead of just 'construction of a dc generator . A DC machine consists of two basic parts; stator and rotor. Basic constructional parts of a DC machine are described below.
Yoke: The outer frame of a dc machine is called as yoke. It is made up of cast iron or steel. It not only provides mechanical strength to the whole assembly but also carries the magnetic flux produced by the field winding.
Poles and pole shoes: Poles are joined to the yoke with the help of bolts or welding. They carry field winding and pole shoes are fastened to them. Pole shoes serve two purposes; (i) they support field coils and (ii) spread out the flux in air gap uniformly. Field winding: They are usually made of copper. Field coils are former wound and placed on each pole and are connected in series. They are wound in such a way that, when energized, they form alternate North and South poles Armature core: Armature core is the rotor of a dc machine. It is cylindrical in shape with slots to carry armature winding. The armature is built up of thin laminated circular steel disks for reducing eddy current losses. It may be provided with air ducts for the axial air flow for cooling purposes. Armature is keyed to the shaft.
Armature winding: It is usually a former wound copper coil which rests in armature slots. The armature conductors are insulated from each other and also from the armature core. Armature winding can be wound by one of the two methods; lap winding or wave winding. Double layer lap or wave windings are generally used. A double layer winding means that each armature slot will carry two different coils.
Commutator and brushes: Physical connection to the armature winding is made through a commutator-brush arrangement. The function of a commutator, in a dc generator, is to collect the current generated in armature conductors. Whereas, in case of a dc motor, commutator helps in providing current to the armature conductors. A commutator consists of a set of copper segments which are insulated from each other. The number of segments is equal to the number of armature coils. Each segment is connected to an armature coil and the commutator is keyed to the shaft. Brushes are usually made from carbon or graphite. They rest on commutator segments and slide on the segments when the commutator rotates keeping the physical contact to collect or supply the current.