Power Distribution Essay

Power quality involving voltage occurs in two main ways. These include under voltage and overvoltage. Under voltage occurs when the power in transmission falls below 90% of the total power transmitted for a period of more than one minute. When the power is totally out, the situation is described as a blackout. When the power is fully present, it is simply said to be full power. There is a transition between full power and blackout that is described as brownout. Brownout is identified by dimming of lights, blackout by no lights at all, and full power by all domestic lights been well lit. Under voltage is caused mainly by overloading Overvoltage on the hand refers to a situation when the voltage raises beyond the design limit. Overvoltage is caused by lightening, solar flares, and human activities such as electromagnetic induction. Electrical warfare has been established as another cause of overvoltage. Overvoltage of power can be disastrous. It can lead to destruction of appliances using the power, fires, and other associated problems.
Power frequency may present challenges during transmission. The variation in frequency occurs in three ways. First is the nonzero-low frequency impedance of the electricity circuit. Electrical impedance refers to the opposition a circuit presents to current when voltage passes through it. The nonzero-low frequency occurs when the load draws more power leading to low frequency, and hence the voltage drops. The nonzero high frequency impedance occurs when the load requires large current amount then stops such a demand suddenly. In such a case, the voltage dips or spikes due to inductance. Power harmonics also present a problem when the frequencies are integer multiples of the power system frequency leading to power distortion.
There are several methods used to correct power quality. These include and not limited to, power conditioning and establishment of smart power grids. Power conditioning involves modification of the power to improve its quality. It involves the use of the uninterruptable power supply that switches off the main power source in the event of a transient (a temporary power problem) in the power line. Large surge protectors are placed in power lines to stop overvoltage. Electronic filters are installed at convenient sections of the power line, even at the end user point to remove power harmonics. Modern systems have phasor measurement units placed in the power networks monitor, and in some instances correct the anomaly automatically. Smart grids have rapid sensing; automated responses in the power network that sense, and correct the power problem and restore its quality.
Energy demand is cyclic due to several factors. Seasons affect the demand for power. During the winter, a lot of power would be required to heat the house more than in summer. However, in summer more power may be required to cool and moderate temperatures in the rooms, but at least not more than required in winter. During the day, less energy is required for lighting compared to night time. In general, the demand of power varies greatly, and can even be affected by festive seasons or days when work in industries is mainly off.
The cost of production of power and its transmission is too huge in most instances. This leads to trading of power between utility companies. The cost associated with the maintenance of both systems may be too high. In some instances, the technicalities involved in both are different, hence requiring trade between the utility companies. Some utility companies have already established framework that would be appropriate for transmission of power. Others may be controlling the areas of production and the associated resources like lakes, rivers hence necessitating the trade.
Power outages are caused by the following; natural causes as lighting that damage the power circuits or transmission lines by hitting a tree that then falls on the line. Ice may build up on a tree making then lean on power lines creating a short circuit and hence a blackout. Wind, tornadoes, and hurricanes damage the power line and hence cause blackouts. Other accidents like vehicle accident involving the power line may also cause blackouts. Over usage can also lead to blackouts.