2100 Words9 Pages

ABSTRACT

In an electric power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. The higher currents increase the energy lost in the distribution system, and require larger wires and other equipment. Because of the costs of larger equipment and wasted energy, electrical utilities will usually charge a higher cost to industrial or commercial customers where there is a low power factor. A high power factor is generally desirable in a transmission system to reduce transmission losses and improve voltage regulation at the load. It is often desirable to adjust the power factor of a system near to unity. PFC schemes may be applied by an electric power transmission*…show more content…*

The PFC schemes can be done by using different converters viz,.buck, boost, buck-boost, Cuk, SEPIC and Sheppard - Taylor converters. The implementation of buck converters is explained in [1] and the use of buck converter[8] has the limitation of performing only buck operation[9]. Another disadvantage is that isolation cannot be provided by the converter. PFC scheme using boost converter is detailed in [2] and [3] and the disadvantage of using boost converter is that it cannot perform buck operation. [4] gives the PFC scheme based on buck-boost converters and the main demerit in using buck-boost converter is polarity inversion, i.e, the output will be in opposite polarity to the input. The Sheppard-Taylor topology is explained in [5] and the demerit of using Sheppard-Taylor is the control of the two synchronized switches is difficult. Cuk converters given in [6] also have the disadvantage of Polarity inversion. The comparison of different schemes is done in*…show more content…*

Figure 4 Equivalent circuit when switch is OFF

IV.DERIVATION OF STEADY STATE MODEL OF SEPIC CONVERTER The transfer function using steady state analysis is given by the formula The input matrix is given by = AX + BU

When switch is ON the input matrixis given by When switch is OFF the input matrix becomes The ouput matrix equation is given by

Y = CX + DU

Y=

Where D = [0]

And A=A1d + A2 (1-d)

B = B¬1d + B2 (1-d)

After computation the matrices are given as, A = ; B = ; C =

By substituting these values in the formula T.F=〖C[SI-A]〗^(-1) B+D the transfer function can be obtained. It is given by

T.F=

V. TUNING OF A PID CONTROLLER USING TYREUS-LUYBEN METHOD

The steps to tune the PI controller using Tyreus-Luyben method [7] are given as follows Determine process transfer function Implement proportional control and introduce set point by setting Ki and Kp at minimum values Increase the value of Kp until sustained periodic oscillations are obtained Record ultimate gain and period Evaluate control parameters as prescribed by TYREUS-LUYBEN method as

In an electric power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. The higher currents increase the energy lost in the distribution system, and require larger wires and other equipment. Because of the costs of larger equipment and wasted energy, electrical utilities will usually charge a higher cost to industrial or commercial customers where there is a low power factor. A high power factor is generally desirable in a transmission system to reduce transmission losses and improve voltage regulation at the load. It is often desirable to adjust the power factor of a system near to unity. PFC schemes may be applied by an electric power transmission

The PFC schemes can be done by using different converters viz,.buck, boost, buck-boost, Cuk, SEPIC and Sheppard - Taylor converters. The implementation of buck converters is explained in [1] and the use of buck converter[8] has the limitation of performing only buck operation[9]. Another disadvantage is that isolation cannot be provided by the converter. PFC scheme using boost converter is detailed in [2] and [3] and the disadvantage of using boost converter is that it cannot perform buck operation. [4] gives the PFC scheme based on buck-boost converters and the main demerit in using buck-boost converter is polarity inversion, i.e, the output will be in opposite polarity to the input. The Sheppard-Taylor topology is explained in [5] and the demerit of using Sheppard-Taylor is the control of the two synchronized switches is difficult. Cuk converters given in [6] also have the disadvantage of Polarity inversion. The comparison of different schemes is done in

Figure 4 Equivalent circuit when switch is OFF

IV.DERIVATION OF STEADY STATE MODEL OF SEPIC CONVERTER The transfer function using steady state analysis is given by the formula The input matrix is given by = AX + BU

When switch is ON the input matrixis given by When switch is OFF the input matrix becomes The ouput matrix equation is given by

Y = CX + DU

Y=

Where D = [0]

And A=A1d + A2 (1-d)

B = B¬1d + B2 (1-d)

After computation the matrices are given as, A = ; B = ; C =

By substituting these values in the formula T.F=〖C[SI-A]〗^(-1) B+D the transfer function can be obtained. It is given by

T.F=

V. TUNING OF A PID CONTROLLER USING TYREUS-LUYBEN METHOD

The steps to tune the PI controller using Tyreus-Luyben method [7] are given as follows Determine process transfer function Implement proportional control and introduce set point by setting Ki and Kp at minimum values Increase the value of Kp until sustained periodic oscillations are obtained Record ultimate gain and period Evaluate control parameters as prescribed by TYREUS-LUYBEN method as

Related

## Nt1310 Unit 6 Lab Report

631 Words | 3 PagesThis most likely affected the angle between the board and string. Therefore we then could have used inaccurate quantities when determining our answer. Another source of error that could have happened would be failure to account for a factor. An example of this would be station number four. To determine the weight of the board we used a leaning tower which had a “hidden” weight.

## The Cox Proportional Hazard Model

705 Words | 3 PagesUnlike polynomials, allow for a more local fit to the data and fitting after the knots can be limited to the linear. Generally, there are three methods to estimate splines: smoothing splines, polynomial splines and penalized splines. Better performance of polynomial splines depends on the number and location of knots. To overcome this problem, smoothing splines uses all of points as knots. But when you have a large number of discrete time points, the number of parameters that must be estimated to be high and this is will be complicated calculations.

## Descarte's Theory Of Substance Dualism

737 Words | 3 PagesMost famously advocated by René Descartes, substance dualism is the view that minds, which are essentially thinking and consist of mental substance, and bodies, which are necessarily extended and made of material substance, are ontologically separate entities. The material and mental have entirely different natures, so a mind cannot be equivalent to a body. Human beings, therefore, must be mixtures of the two substances. Substance dualists assert that, despite lacking properties in common, mind and body connect through the capacity of each to causally affect the other (Kim 34). While this position may initially appear intuitive and commonsensical, Descartes and subsequent dualists have faced a multitude of challenges concerning mental causation.

## The Advantages Of Covariance-Based Approaches

821 Words | 4 PagesNevertheless, covariance-based approaches produce severe modeling errors, which lead unreliable results when a model is in mixed constructs. While, PLS is capable of estimating both reflective and formative constructs under athe same model (Lowry & Gaskin, 2014). PLS is sensitive to moderator effects than most of the covariance-based approaches are. Moreover, PLS is better handling measurement errors, thus this characteristic of PLS helps to studies that have smaller sample sizes. Furthermore, in case of a complex model, covariance-based approaches require an enormous sample size for precise estimations.

## Furnham And Mak Analysis

745 Words | 3 PagesThey believe that even in the same country, commercial channels differ considerably in their viewing figures, style, and funding. For example being national, regional and their focus of audience affect their commercials. Therefore they assert that it is “near-impossible to find “equivalent channels” in different countries” (Furnham & Mak 1999). The second is the sample equivalence. The time of the day is different for viewer categories therefore it effects the commercials.

## Michael Porte's Competitive Advantage

837 Words | 4 PagesAdditionally, efficient distribution channels, optimal outsourcing and vertical integration, bargaining power to negotiate the lowest price for production inputs as well as high buying capacity all participate in making cost leadership a go-to strategy for high return on investment and profitability. The possible downsides of this strategy can vary from low workers remunerations to exploitation of unskilled workers. The advantages of cost leadership are often threaten by external business environment threats such as higher minimum wages laws. Examples of successful cost leadership organisations: WAL-MART.INC (ASDA), Costco, MCDONALD 'S, IKEA. Cost advantages stem from the fact that a company can quickly reap higher profit margins despite selling products or services at competitors price due to lower production costs.

## Porter's Five Forces In The Trucking Industry

726 Words | 3 PagesThe threat of new entry can change in the trucking industry depending on the scale you want to implement on. Cross-country trucking, for example, would have a much higher entry cost than trucking within a couple of states, as for the former you would need many more trucks, drivers, and fuel, all of which cost money. While even a small number of trucks and drivers costs a large amount of money, this number is more palatable for many individuals, which leads them to start their own small scale trucking company. It is much easier to enter into the LTL trucking industry than it is to enter the TL trucking industry. For many companies that do both, their profit margins on LTL or VLTL tend to be higher than their profit margins for TL.

## Essay On Diesel Truck

619 Words | 3 PagesWith the parts that do not last long that means regular maintenance and up keeping when something goes wrong. Although a diesel truck is more expensive, you can expect much more out of it. A 2015 Ford XLT Super Duty is around $51,000 brand new. Although it is much more expensive, the price comes with dependability. With a diesel engine, the parts are made stronger and makes the truck much more dependable.

## Disadvantages Of Economic Growth

1571 Words | 7 PagesINTRODUCTION Economic growth is defined as the increased capacity of an economy to be able to produce goods and services in comparison from one period of time to another. This is figured by the genuine Gross Domestic Product (GDP) and development, and is measured by utilizing genuine terms such as “Balanced Inflation”. These terms help to remove any distorted views on the perceived outcome of inflation on the cost of merchandises produced. Likewise, Economic growth is related to the high expectations in a person’s standard of living. If the standards are high, it wouldn’t be beneficial for the economy as the working class individuals will face a lot of trouble.

## And Disadvantages Of Foreign Direct Investment

1029 Words | 5 PagesTake note that larger corporations would usually offer higher salary levels than what you would normally find in the target country, which can lead to increment in income. List of Disadvantages of Foreign Direct Investment 1. Hindrance to Domestic Investment. As it focuses its resources elsewhere other than the investor’s home country, foreign direct investment can sometimes hinder domestic investment. 2.

### Nt1310 Unit 6 Lab Report

631 Words | 3 Pages### The Cox Proportional Hazard Model

705 Words | 3 Pages### Descarte's Theory Of Substance Dualism

737 Words | 3 Pages### The Advantages Of Covariance-Based Approaches

821 Words | 4 Pages### Furnham And Mak Analysis

745 Words | 3 Pages### Michael Porte's Competitive Advantage

837 Words | 4 Pages### Porter's Five Forces In The Trucking Industry

726 Words | 3 Pages### Essay On Diesel Truck

619 Words | 3 Pages### Disadvantages Of Economic Growth

1571 Words | 7 Pages### And Disadvantages Of Foreign Direct Investment

1029 Words | 5 Pages