Why is reactive power compensation needed in a power. Reactive power compensation of transmission lines by. It can be capacitive leading or inductive lagging reactive power, although in most. As a result of the april 2004 report and recommendations of the. Real power or active power is the true power given to any load. The main reason for reactive power compensation in a system is. It limits the flow of load reactive current in lines and. For simplicity let us consider only the inductive reactance.
It comes in two flavors, inductive or capacitive depending on whic. Reasons for failure of transmission lines and their prevention strategies 2 event of the ice cover the intensity of work, repair and maintenance takes relatively longer time as compared to the other places. Reactive power is power that is stored during one part of the ac waveform, and returned a few milliseconds later during another part of the waveform. Transmission line parameters of different conductors which are used at sub station for bus bar connection and also the transmission lines are. To get this modeling and control of sssc for reactive power compensation in transmission lines project,visit us on. Voltage control in an electrical power system is important for proper operation for electrical power equipment to prevent damage such as overheating of generators and motors, to reduce transmission losses and to maintain the ability of the system to withstand and prevent voltage collapse. By reactive power compensation we can control the power factor and reduce the consumption of electricity. Shunt compensation of reactive power can be employed either at load level, substation level, or at transmission level. In this chapter the conventional methods employed for reactive power compensation, their relative merits and demerits, desirable features. Highvoltage transmission lines are sources of reactive power in the power system, where the reactive power depends on the power transmitted in the line, its length and parameters of the line itself. Reactive power control in electrical power transmission system.
The term reactive power compensation is for the higher capacity systems. Series compensation is the method of improving the system voltage by connecting a capacitor in series with the transmission line. With further improvement of controls, development of semiconductors and new arrangements of vsc technology todays reactive power compensation is a key method to establish a reliable ac power transmission. Basics of electricity power flow on ac transmission lines pjm2014 71120. The formation of ice cover is because of cold weather, air and humidity.
In present scenario, it becomes more important to control the power flow along the transmission lines to meet the needs of power transfer. There are two aspects to the problem of reactive power compensation. The principles of both, shunt and series reactive power compensation alternatives, are described below. The optimization can be done by adjusting reactive power in the transmission line. Reactive power compensation technologies, state ofthe. Reactive power compensation for transmission and distribution. Reactive power compensation is an important subject in power electronic systems. Many applications have been developed to enhance the stability of power systems with the utilization and. The proposed strategy includes the coordination of the performance of transient stability with an. As a general practice, the 500va control supply transformers will not require such compensation. In doing so, reactive power compensation decreases overall energy consumption and has lasting economic and environmental impacts.
For public companies, specifically those in the electric energy transmission segment. This is all about the importance of reactive power. The circuit diagrams and control characteristics of each compensation device are presented with its analytical expressions. In recent years static controllers and power electronics components are used. Electric power transmission lines, property values, and compensation article pdf available in journal of environmental management 271. A lot of research works have been carried out on the above listed aspects. Why is it desirable to inject reactive power into a transmission system. The effects of electric transmission lines on property. A study of reactive power compensation in power system.
Reactive power compensation in transmission line using. Since it is referred to the generator delivered power if it is negative that means the generator is underexcitated and gets reactive power from the gridinfinite. This paper presents the reactive power management for 765 kv extra high voltage ehv transmission system. Pdf transmission system performance improvement through. More power plants, substations, and transmission lines need to be constructed. Reactive power compensation in ac power systems ersan kabalci. Figure 1 shows the principles and theoretical effects of shunt reactive power compensation in a basic ac system, which comprises a source v.
This leads to the poor stability and voltageregulation. Importance of reactive power in power generation and. Reactive power and voltage relationship in power transmission line sumit maitra. In general, transmission lines connect the systems generators to its distribution substations. Their paper employs the shunt connected compensation statcom based facts devices for the control of voltage and the power flow in long distance transmission line.
What is the importance of reactive power in transmission. They were then asked a variety of questions concerning appropriate regulatory responses to emfs, willingness to pay for exposure control, etc. Transmission losses in these power networks are of great concern to engineers. Pdf effect of reactive power compensation on voltage profile.
The effects of electric transmission lines on property values. Principles for efficient and reliable reactive power. The calculation of the three basic transmission line parameters is presented in the following sections 17. The issues of reactive power compensation in highvoltage. Why is it desirable to inject reactive power into a.
At high levels of load, however, transmission lines absorb reactive power and thereby lower voltages. Chapter 8 reactive power compensation in ac power systems. The increased electric power consumption causes transmission lines to be driven close to or even beyond their transfer capacities resulting in overloaded lines and congestions. The less loaded a transmission line is, the greater reactive power it generates. Reactive power compensation in transmission lines using static var compensator by simulation in etap tamojit chakraborty dept. Importance of reactive power for system electrical notes. The main reason for reactive power compensation is to regulate the voltage magnitude. In other words, in series compensation, reactive power is inserted in series with the transmission line for improving the impedance of the system. It essentially facilitates the flow of energy in an electric system, and is generated or absorbed by many equipment connected to the power system network. Fundamental concepts of reactive compensation hvdc. Voltage stability of a system is affected by reactive power limit of the system.
It accomplishes useful work like lighting lamps, rotating motors, etc. Reactive power compensation rpc offers the most economic mean s to do so. Calculating the reactive power of a transmission line. Elaborating a risk matrix will help administrators make more informed decisions and provide a clearer vision of projectrelated risks. Ac power supply systems produce and consume two types of powers.
Transmission line compensation using neurofuzzy approach for reactive power 1gurmeet, 2daljeet kaur 1,2department of electrical engineering 1,2giani zail singh college of engg. Transmission lines are powerful investments realmoney. I would like to thank the readers for spending their time on this article. Here is a question for interested readers what is power factor and how can we achieve power factor compensation. Pdf reactive power compensation of transmission lines. To develop a good, qualitative understanding of the.
Since most loads are inductive and consume lagging reactive power, the compensation required is usually supplied by leading reactive power. Abstract in order to improve the stability of the system and reduce the power system losses, this paper proposes a grenade explosion algorithm for the reactive. Conclusion from all the previous discussion we can conclude reactive power compensation is a must for improving the performance of the ac system. Objectives describe the basic makeup and theory of an ac. Note that the compensation might be both positive and negative reactive power in, or reactive power out. This paper discusses a simulation to model power consumption in. The impedance of transmission lines and the need for. Background and policy issues congressional research service 3 facilitate power sales. Historical overview on dynamic reactive power compensation. Moreover repair and maintenance is not easy for the maintenance staff.
Reactive power compensation serves to increase the power factor of large industrial loads and increase the efficiency of power transmission. The quantity x l is the perphase reactance, l is the perphase inductance, and r is the perphase resistance. From all the previous discussion we can conclude that reactive power compensation is a must for improving the performance of the ac system. Thus, it improves the power transfer capability of the line. Transmission line parameters of different conductors which are used at substation for bus bar connection and also the transmission lines are.
Unlike most power generators, transmission lines are costplus assets, and those assets earn solid returns through good times and bad. Thumb rulescharts are available for the reactive power compensation of standard motor control center or motors at low voltage. Reactive power compensation is used to control the power system voltage stability and increase the power transfer capability of the transmission line. Reactive power var compensation is nothing but the control of reactive power to enhance the performance of ac system. Reactive power compensation techniques in transmission lines. Fundamental concepts of dynamic reactive compensation and hvdc transmission brian k. Var compensation is defined as the management of reactive power to.
By reactive power compensation we can control the power factor and reduce the. Facts devices improve the reactive power flow in system thereby improving voltage stability and these are used for controlling transmission voltage, power flow, dynamic response and reducing reactive losses in transmission lines. If is23 a then line reactive power it is xis223268. The maximum power transfer of transmission system can be increased by shunt var compensation 3. Reactive power compensation technique in transmission lines. Yongan deng, masc student at concordia university 1. Thus reactive power is essential to maintain the voltage to deliver active power through transmission lines. Pdf reactive power compensation in power transmission. The paper gives an overview from the early days of reactive power compensation towards the present transmission system.
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