Generators Used in Wind Power Term Paper
- Length: 8 pages
- Sources: 15
- Subject: Energy
- Type: Term Paper
- Paper: #54999629
Excerpt from Term Paper :
The little occasion utmost torque of a rotor twice-fed electric machine is of higher frequencies and capabilities unlike other machines used within the frames of generating power in the society. Several avenues of operation are used within this notion of realizing the existence and consequence of having a firm body of generating any amount of energy to be used in the field. In order to foster equitable management of the practices and operations of producing energy in the field, there is much reputation of the available facilities to be used as capable parameters in designing the amount of energy needed for production in the field (Flannery, 2008).
Example of the machine
Squirrel cage induction generator
In this machine, the field windings are used within the stator of the motor and the rotary movement of the field of magnetism in the rotor. The relational motion that exists between the field of magnetism and movement of the rotor produces an induced electric current within the bars of conduction in the available fields. In revolve, the currents lengthwise in the conductors changes in a manner similar to the magnetic behavior of the motor (Eremia, 2013). This results in the creation or production of a force that appears to be acting at a tangent orthogonal to the rotor. This force is a subject matter to the generation of a torque in the shaft. The rotor becomes one of the factors of operation that are used within the stakes of the magnetic field but within the notion of lower rates in rotation. The lower rates of rotation result in what is termed as slip and increase in the overall amounts of loads (Rashid, 2010).
The functionality of many conductors is found within the range of torque functionalities. The lengths of the available torques and other gadgets of operation are reflected within a single mechanistic platform of reflection on the fluctuations of torque and their resultant speeds. Reducing the production of the rotor ensures the existence of few instances of a large production of noise and many related features in the production avenues. The skewing of the conductors is done solely to reduce the instances and chances of noise pollution in the process of producing energy in the field (Earnest & Wizelius, 2011).
The function of the iron core is related to the magnetic fields that happen through the rotor conductors. This happens because the magnetic field in the rotor is alternating with time. The core aims are done within the facet of construction of the transformers in order to reduce energy loses that occur within this category of operation in the field. The facet of operation within this category of the machines is done with the use of thin laminations, separated by varnish insulation, to reduce eddy currents circulating in the core. The material I made of a material of low carbon, but with high silicon iron, that has a number of resistivity of pure iron in them (Ackermann, 2012).
This similar basic design is used within the single-phase and three-phase motors over a wide range of sizes. The category of rotors for three-phase will have variations in depth and shape of bars. This is done in order to suit the design classification. Within the efficiency parameters of this material, thick bars have good torque and are efficient at low slip. This happens because of the fact that they have lower conductivity to the EMF. When the slip of the material increases, skin effect starts to reduce the effective depth and increases the resistance. This matter has its own effects as it results in reduced efficiency but still maintaining torque (Kaz-mierkowski et al., 2002).
Effectiveness and differences in their topologies
A single-phase motor and a copper pipe are supposed to be used in order to have a clear demonstration of the stator . When a good amount of AC power is supplied to the stator, there is a development of an alternating magnetic field that revolves around the stator. In case a copper pipe is inserted inside the stator, there occurs a new facet of induction in the induced current pipe. This current works with production of the current that produces another magnetic field. The relationship that is established between the stator-revolving field and motor induced field leads to the production of a torque and thus rotation. This rotation is very instrumental in the general generation of current or power in the field (Flannery, 2008).
Diagram of Squirrel cage induction generator
Permanent magnet synchronous generator
A permanent magnet synchronous generator uses the principle of the excitation. This is one of the fields where the excitation field is provided by a permanent magnet and not the coil as in other machines. Several synchronous generators are the majority source of marketable power (Pyrhonen et al., 2008). These gadgets are commonly used to convert the mechanical power output of many sources like gas turbines, steam turbines, and other types of engines like reciprocating engines, hydro turbines, and wind turbines into electrical power for the grid. These materials are referred to as synchronous generators. The reason or explanation behind this notion is because of the speed of the rotor that must always match the supply frequency (Rashid, 2010).
Within the normalized avenue of permanent magnet generator, the magnetic field within the rotor is produced through the influences of the permanent magnets. There are other categories of generators that use electromagnets to manufacture electric forces within the rotor windings (Earnest & Wizelius, 2011). The direct current within the rotor field winding is determined through a slip-ring congregation or manufactured by a brushless exciter on the same shaft. This categorical facet differentiates between the several facets of performance within the three major types of power generation mechanisms (Kinnunen & Lappeenranta, 2007).
The Permanent magnet generators within this category of the machine do not need a DC supply for the excitation circuit. Moreover, it does not require the need for slip rings and contact brushes. Nonetheless, large permanent magnets are pricey. This puts restrictions to the economic rating of the machine as compared to the other categories of the machines. The flux density of high performance permanent magnets is of little effect. The air gap flux cannot be controlled. This means that the voltage of the machine cannot be regulated with ease. This is another feature that states the difference between the two categories of the machines in the market (Gieras et al., 2008).
Diagram of Permanent magnet synchronous generator
Generators used in power generation appliances are of varying categories. From the clear understanding of the varying levels of performances in the three generators, there are some of the basic differences in their mechanistic properties and workability in the field. The Permanent magnet synchronous generator has the advantage of being flexible in its use in the field. Large voltages of power can be generated from this device. Moreover, the machine is effective, efficient, and covers a large degree of performance in the field of use. Unlike the other generators, the permanent magnet synchronous generator is multifaceted in nature. Nonetheless, it is highly consuming when it comes to management of the other features of use and management in the field of power production. The Squirrel cage induction generator has the advantage of being simple and easy in its use. Nonetheless, it is quite expensive and does not meet the diverse requirements of being fundamental in energy production in the market. On the other hand, the doubly fed induction generator is the best used in the field. It produces energy in continuous motions and mechanisms that are within the construct of many power generation plants. It beats the other generators in the field. Nonetheless, it is quite expensive for normal companies and organizations in order to afford and make use of them in the field of energy production.
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