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Difference between AC and DC Transmission System & Power Lines

In earlier time, the electrical strength transmission was carried out in DC due to the following benefits over AC.

Advantages of DC Transmission
There are conductors are utilized in DC transmission at the same time as 3 conductors are required in AC transmission.
There are not any inductance and surges (High Voltage waves for very quick time) in DC transmission.
Due to the absence of inductance, there are very low voltage drop in DC transmission lines as examine to the AC (if both Load and Sending give up Voltage is same)
There is not any concept of Skin impact in DC transmission strains. Therefore, conductor having small go sectional location is required in DC transmission line.
A DC System has a less capability pressure over AC device for same Voltage level. Therefore, a DC line requires less insulation.
In DC System, there may be no interference with other communique lines and systems.
In DC Line, Corona losses are very low in comparison to the AC transmission strains.
In High Voltage DC (HVDC) Transmission traces, there are not any dielectric losses.
In DC Transmission system, there are not any difficulties in synchronizing and associated stability troubles.
DC machine is more efficient than AC, consequently, the fee of charge of Towers, Poles, Insulators, and conductor are low so the device is low-cost.
In DC System, the velocity manipulate range is more than AC System.
There is low insulation wanted within the DC system (approximately 70%).
The price of DC cables is low (due to low insulation).
In DC Supply System, the Sheath losses in underground cables are low.
DC machine is appropriate for High Power Transmission based totally on High Current transmission.
In DC System, The Value of charging contemporary is pretty low, therefore, the duration of the DC Transmission strains is extra than AC lines.
Related Post: AC or DC – Which One is More Dangerous And Why?

Disadvantages of DC Transmission:
Due to commutation problem, electric powered strength can’t be produced at High (DC) Voltage.
In High Voltage transmission, we cant step-up the extent of DC Voltage (As Transformer received’t paintings on DC).
There is a hassle of DC switches and circuit breakers (and they are high priced too).
The motor generator set is used to step down the level of DC voltage and the performance of Motor-generator set is lower than a transformer.
DC transmission device is more complicated and high priced as compared to the AC transmission machine..
The degree of DC Voltage can’t be changed (step-up or step-down) without difficulty. So we cannot get preference voltage for electric and electronics appliances (which includes five Volts, nine Volts 15 Volts, 20 and 22 Volts and so forth) at once from the transmission and distribution traces.
Related Post: Difference among AC Drives and DC Drives

AC Transmission:
Nowadays, the era, transmission and distribution of electrical power has more often than not been in AC.

Advantages of AC Transmission System
AC Circuit breakers are less expensive than DC Circuit breakers.
The repairing and preservation of the AC sub station is easier and less expensive than DC Substation.
The Level of AC voltage can be improved or reduced via the use of step up and Step down transformers.
Related Post: Why Does A Capacitor Block DC But Pass AC?

Disadvantages of AC System
In AC line, the size of the conductor is grater than the DC Line.
The price of AC transmission lines is greater than DC Transmission lines.
Due to pores and skin effect, the losses in AC machine are more.
Due to the capacitance in AC transmission strains, a non-stop energy loss takes place whilst there is no load on the energy lines or line is open at all.
There are some extra line losses due to inductance.
More insulation are required in AC transmission machine.
The corona losses arise in an AC transmission line gadget.
AC transmission traces intrude with other communique lines.
There are balance and synchronizing problems in AC System.
AC transmission machine is much less efficient than the DC transmission System.
There are problems in controlling the reactive strength.
Related Post: Why Do Electronic Circuits Use DC Current in preference to AC?

The above evaluation indicates that DC transmission device is better than the AC transmission gadget but nonetheless, most people of strength transmission is completed in AC power lines due to fee and makes use of of transformers for converting the level of voltages at different degrees for one-of-a-kind functions.

Although, mercury arc rectifier, thyratron, diodes and semiconductors can be used to without difficulty convert AC into DC and DC into AC. Therefore, some international locations transmit the electric electricity via DC power traces. The variety of those DC electricity transmission is as much as 100kV to 800kV+.

Good to understand:

Recently in China, a 12GW power changed into transmitted at 11kV DC over a distance of 3300km.
In addition, the longest HVDC electricity transmission line in the international is 2385km in Madeira, Brazil.
Related Posts:

What is the Role of Capacitor in AC and DC Circuit?
Why Can’t We Store AC in Batteries rather than DC?
Difference Between AC and DC Resistance – Which One is More?
Why an Inductor acts as a Short Circuit in DC Supply?
Why Does A Capacitor Block DC But Pass AC?
Is Lightning AC or DC?
FACTS – Flexible AC Transmission System – Types of FACTS Controllers & Devices
What is HVDC? – High Voltage Direct Current Power Transmission
Types of HVDC Systems and MTDC Configurations
Differences Between HVAC and HVDC – Power Transmission
Advantages of HVDC over HVAC Power Transmission

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