Figure 3-1 shows a schematic diagram of a typical hybrid wind–diesel generation system. The main components of a hybrid wind–diesel power generation system are: wind turbine with associated controls, diesel engine; electrical generator with power electronic controllers (PEI), loads and bidirectional power electronic converter.
Wind turbine
The wind turbine should be capable of capturing maximum energy by Maximum Power Point Tracking (MPPT) during low wind speed as well as high wind speed conditions. The tip speed ratio has to be brought to a particular value to achieve MPPT during low speed conditions. This can be done by adjusting the electromagnetic torque of the generator by employing suitable power electronic controllers so that the quadrature axis component (the torque-producing component) of current in the three phase AC generator is appropriately manipulated. During higher wind speed conditions (greater than the rated wind velocity for which the turbine is designed), pitch control is activated so that generator capacity is not exceeded and the currents and voltages are within safe limits. During this condition, the generator will operate under constant power control.
Diesel engine/ generator
The generators used with the diesel engines are wound field three phase synchronous generators whose terminal voltage is maintained at the rated value by means of excitation control. The governor control mechanism of diesel engine controls the frequency. Normally the generator used along with wind energy is an induction generator (IG) or a PMSG. For night operation of a hybrid system a DFIG is used.
Squirrel cage induction generators (SCIG) with self-excitation which work in the generating mode only at super-synchronous rotor spee...
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...so within its safe speed limits. The load-side converter is controlled by chopper and an inverter as discussed above for maintaining the voltage across the DC link capacitor at a constant value.
DFIG control using current linked converters
The current linked converter uses thyristorized converters on the rotor side as well as on the load side for controlling real power. Such a configuration is as shown in fig 3-4. The motoring operation is done at sub-synchronous speed and generating operation for super-synchronous speed as the voltage can be reversed in both the converters, depending upon the firing angle range at which each of them is operating. For motoring operation at sub-synchronous speed the rotor side will function as a rectifier and the load-side converter will be operating as an inverter. This will be opposite in the super-synchronous generating mode.
The first type of forced induction system is the turbocharger. A turbocharger is essentially the same as a supercharger, except where they get their power from. A turbocharger is powered by exhaust gasses that have been produced by the engine and are forcing their way through the turbofold, or the exhaust manifold that the turbo is housed in. The exhaust gas pushes its way through the turbocharger and hit the turbine wheel. Vehicles that usually find the need for a turbocharger from the factory are four or six cylinder engines. Standard in most European vehicles such as Mercedes, Audi, Volkswagen and Volvo. These cars are known for their small displacement motors, and great gas efficiency, due to this setup...
These include the history of windmills and their role concerning the survival in the immense plains that range from east of the Rocky Mountains to the Mississippi River. The rise of the economic condition of those living around the wind farms along with the surge of investments from energy companies. Finally, the promising data relating to the amount of energy produced, and the consequences they will have on the environment. In the later and longer part of the article, the possible negative results or wind farms are brought up. Primarily, the points against wind farms have to do with the conservation of wildlife. This is separated into two sections, the first addresses the dangers wind turbines present to birds, the other on the dangers presented to bats.
A direct current in a set of windings creates a polar magnetic field. A torque acts on the rotor due to its relation to the external magnetic field. Just as the magnetic field of the rotor becomes fully aligned with the external magnetic field, the direction of the current in the windings on the armature reverses, thereby reversing the polarity of the rotor's electromagnetic field. A torque is once again exerted on the rotor, and it continues spinning.
The year is 2200. The world is going through a fossil fuel shortage. Oil reserves are almost completely consumed and it is becoming impossible to find new fossil fuel sources. Not prepared for this event to occur, The United States, has no alternative options. As a result of the oil shortage, the standard of living deteriorates. Heat in homes, supermarkets full of food, and transportation, all basic necessities taken for granted, will be depleted because fossil fuels are used to power almost everything. The key to the prevention of this future is renewable energy. Unfortunately the support for the use of renewable energy is weak and ineffective. Unless the US puts forth effort to research and promote the use of renewable energy to consumers, conversion from fossil fuels to renewable energy will no longer be an option.
Energy is the basic necessity of daily life. Nowadays, dependence on fossil fuels for energy needs becoming lower in numerous countries due to the potential of renewable energy to supply sustainable energy to the huge populations in many developing countries who are short of clean and continues energy. Generally, renewable energy can be defined as energy that is derived from natural resources which are constantly replenished and theoretically inexhaustible. Fossil fuels on the other hand can be described as energy that cannot be renewed and will eventually diminish. Thus, in many developing countries renewable energy is the alternative energy to replace non-renewable energy or commonly known as fossil fuels. In addition, according to Sorensen (2004), there is a greater demand for renewable energy sources nowadays due to the uncertainty of fuel price rise in living expenses. Commonly, there are many types of renewable energy available in our world such as wind power, biomass energy, solar energy, hydroelectric power and geothermal energy. However, the main three example of renewable energy are hydroelectric power, solar and biomass energy (Refer to Figure 1 in Appendix 1).
The invention of internal combustion engines in the early 19th century has led to the discovery of utilisation of cheap energy that is petroleum and this enabled the world to develop and progress into the modern world today. Humans were able to accomplish more work done with little manual labour, using internal combustion engines powered by fossil fuels. Internal combustion engine are mechanical power devices that convert heat energy to mechanical energy with the combustion process taking place in a system boundary (Rolle, 2005). Among the internal combustion engine invented in the 19th century were the Otto engine, Diesel engine and gas turbine engine. Gas turbine engine is one of the popular engines used today due to its high torque per weight ratio relative to other types of internal combustion engines. As explained by Cengel and Boles (2011), the gas turbine engine works on a 6 stages process, namely air intake, compression, fuel injection, combustion, expansion and exhaust (refer to Figure 1 in Appendix 1).
The Wind Turbine is a device that converts the kinetic energy of the wind into kinetic energy of turbines. The turbines turn to generate electricity but they work only when there is wind. The efficiency is 30-40%. The environmental impacts are needs many large turbines to generate electricity which can be noisy and unsightly. Turbines may endanger birds and bats.
The wind is an incredibly valuable renewable energy source and is in the forefront of renewable energy developments. It is used to convert wind energy into energy that can be harnessed and used via a variety of methods, including; wind turbines, windmills, sails and windpumps. For a renewable energy source, however, it is wind turbines that are used to generate electricity (see figure 1). Wind power has been used for this since the end of the nineteenth century, after Professor James Blyth of the Royal College of Science and Technology first attempted it (Boyle, 2012). However, It wasn’t until the 1980s that using wind power technology was sufficient enough to experience a rapid growth of the technology.
Why do we need to rely on renewable sources? Most of the energy that we use today come from fossil fuels such as natural gas, coal, and oil. All of these resources are non-renewable, it can finish one day. In order to have a better world and a healthy environment for the future, people are trying to obtain energy from natural resources instead of non-renewable sources. In the lecture “Renewable energy resources” (2014), Mistry focuses on some advantages and disadvantages of renewable energy. There are different kind of resources that we can use in order to produce renewable energy. Solar power, wind power, hydroelectric power are just some of the kinds of renewable energy that might be the best options to obtain energy because they come from
In chapter thirteen of our book, Environment by Raven and Berg, it shows us just how important renewable energy sources are. Currently the United States of America thrives on the use of fossil fuels and nuclear power. The main problems with these types of fuel are that they are both limited and can be extremely harmful to our environment. They cause global warming, air pollution, acid rain, and oil spills (Environment), and not only that, but in the grand scheme of things, these sources really aren’t even that cheap of a fuel source. There are many alternatives to these all but outdated fuel sources.
Wind is a form of solar energy. The term wind energy describes the process by which the wind is used to generate electricity or mechanical power. Wind turbines convert mechanical energy from the wind into electrical power. Wind turbines usually have three main parts. There are blades that connect to a central hub, a box behind the blades that contains the generator, and a long stem that connects to the ground. The way how it works is that the wind turns the blades, which spins a shaft that connects to a generator making electricity. After the electricity is produced it is sent through transmission lines to a substation that is sent to business and homes. For the sake of our planet, we must promote a renewable energy economy. Wind power can be a foundation of that sustainable energy future because it provides jobs in states that are building wind turbines, is a renewable energy source, and does not damage our environment. The environment will not be damaged by the pollution, the natural resources will not be used up, and there won’t be generating of hazardous wastes. Welcoming wind energy today will lay the foundation for a healthy tomorrow that will affect everyone in the United States. There are obstacles and challenges that will make it more difficult, but the environmental impact is well worth it to invest more money into wind energy.
The inverter works more or less like a UPS, the inverters are usually bigger and capable of providing greater outputs; they often use a bigger energy storage battery compared to the UPSs. The inverter is suitable both as a backup and for renewable energy
With the depletion of fossil fuel resources comes speculations and debates about alternative energy sources. The world, including the Philippines, is practically dependent on a dwindling non-renewable source of energy. Today, experts are debating about and considering three options: Nuclear, Solar, or Wind Energy. Everyone has been accustomed to the bad image of nuclear energy as a result of the Chernobyl and Fukushima incidents above all others. The popular belief is that radiation from a nuclear meltdown is very harmful to humans and other living things—which is true—and that nuclear power plants are very dangerous and not ideal—which is not. According to Smith, et. al (n.d), all the nuclear disasters that ever occurred were caused by human error and natural disasters like tsunamis, not one because of system failure. Putting the false beliefs aside, with proper engineering and adequate maintenance by experts, a nuclear power plant is a very ideal and viable source of energy for the following reasons:
Deal, W. (n.d.). Wind power: An emerging energy resource.Technology & Engineering Teacher, 70(1), 9-15. Retrieved from http://web.b.ebscohost.com/ehost/detail?sid=a747d6c4-9f9f-4066-be3e-d7d26a427ef2@sessionmgr115&vid=1&hid=114&bdata=JkF1dGhUeXBlPWNvb2tpZSxpcCxjcGlkJmN1c3RpZD1zc2Mmc2l0ZT1laG9zdC1saXZlJnNjb3BlPXNpdGU=
The stator is the stationary component while the rotor is the rotational component of the motor. Usually magnetic fields are created when an electric current is applied to a set of conductive wires wound together (Dixon, 2001). Magnetic fields can also be created using Permanent Magnets (PM). Electrical motors can also work as electrical generators (Correla, 1986). Electrical generators are devices capable of converting mechanical energy into electrical energy. An example would be a wind turbine which works as an electrical generator. It converts the mechanical energy of the rotating shaft caused by wind into electrical energy (Correla, 1986). The focus of this research will ...