# Why are transmission lines rated in kV?

Contents

Because the limiting factor for most transmission lines is the insulation withstand voltage, the insulator size and materials and the air spacing between conductors and the distance above the ground. … But the voltage is always there; ready to deliver power on demand.

## What is kV transmission line?

Transmission voltages are defined as any line with voltage greater than 39,000 volts or 39 kV. The metric abbreviation kV for kilovolts is commonly used when talking about transmission line voltages. Commonly used transmission voltages are 69 kV and 138 kV.

## Why is transmission line 11kV?

But we already know that there are some voltage drop due to the resistance of the transmission lines. For this reason, they transmit 10% extra voltage. … Sending Voltage = 10kV x 10% = 11kV. While the receiving end voltage are 10kV due to voltage drop.

## What is the rating of transmission lines?

An overhead transmission line thermal rating (“line rating”) is a limit on the combination of the line-current magnitude and duration, for the purpose of restricting conductor temperature.

## Why is 400 kV used?

It is first stepped up to 400 kV by a transformer and then transmitted across the country in aluminium cables roughly 2 cm in diameter. High voltages are used because the power loss per kilometre (I2R) for a given power output will be much less at high voltage and low current than at low voltage and high current.

## Why spacers are used in transmission line?

The key function of a phase spacer is to prevent the approach of phase conductors on a high voltage overhead circuit due to formation of ice sleeves and the presence of strong wind. Such natural events can lead to deflection of conductors that are subjected to the increased mechanical loads being generated.

## Why are there 3 power lines?

A three-wire three-phase circuit is usually more economical than an equivalent two-wire single-phase circuit at the same line to ground voltage because it uses less conductor material to transmit a given amount of electrical power. Three-phase power is mainly used directly to power large motors and other heavy loads.

## Why do we use 11kV to 33kV?

It is cheaper to generate at a relative lower voltage and then step it up for transmission. Hence, most power generating plants are designed to operate at 11KV. To generate at 33KV, the size of the motor might be twice as large as the size of 11KV generator.

## What is difference between 11kV and 33kV?

The 11kV lines are used in residential areas and is what feeds the local transformers, which then distributes power to the buildings in the area. 33kV lines on the other hand involve much higher voltages and are used to distribute power from one small sub-station to another.

THIS IS INTERESTING:  You asked: Which changes in an electric motor will make the motor stronger?

## What is the difference between 11kV and 22kV?

RE: 11kV vs 22kV distribution voltage

…22kV can carry twice the load of 22kV. For two reasons for choosing 11kV over 22kV, one is that protection systems would be cheaper and smaller. The other is power correction of an 11kV system would require smaller devices as well.

## What are transmission lines used for?

The lines that carry radio waves from the radio transmitter to the antenna are known as transmission lines; their purpose is to convey radio-frequency energy with minimum heating and radiation loss. Heating losses are reduced by conductors of adequate size.

## What is the effect of line parameters on performance of transmission line?

The performance of transmission line depends on the parameters of the line. The transmission line has mainly four parameters, resistance, inductance, capacitance and shunt conductance. These parameters are uniformly distributed along the line. Hence, it is also called the distributed parameter of the transmission line.

## What is transmission line PPT?

TRANSMISSION LINES A transmission line is used for the transmission of electrical power from generating substation to the various distribution units. It transmits the wave of voltage and current from one end to another. The transmission line is made up of a conductor having a uniform cross-section along the line.

## What is 400kV?

400 kV is the highest voltage in use in the UK. All 400 kV lines are compliant with the public exposure limits, though this needs demonstrating on a case-by-case basis – see more details.

## Is safe distance from 400 kV line?

For the 400 kV, 500 MW line under consideration, the flux density of 1.265 mg is reached when x = 77m; this implies that the safe clearance distance is 77m from the line centre on the either side. Thus, the overall safe clearance distance is 154m.

THIS IS INTERESTING:  What type of motor is used in a hair dryer?

## What does 220 kV substation mean?

220kV substation equipment. … This is accomplished by suitable apparatus called Substation. For example, generation voltage (11KV or 6.6KV) at the power station is stepped up to high voltage (say 220KV or 132KV) for transmission of electric power. The assembly of apparatus (e.g. transformer etc.)