What is corona ring for insulator? What are the benefits of using it? How to install corona ring on insulator? Read on to know about the corona ring for insulator guide.
If you have any questions about corona ring for insulator, you will find all answers right here.
So, keep reading to learn more.
What is corona ring for insulator?
The corona ring is a corona discharge device for preventing the flashover and corona discharge of insulators.
The corona ring is a product that prevents the flashover of insulators in high-voltage transmission lines by discharging the electric field around the insulator string to release and suppress the electric field around the insulator string.
The corona ring adopts a multi-stage structure design, which has good insulation performance and can adapt to various harsh environments. The product has no wind resistance, small size, light weight and easy installation.
The corona ring is mainly composed of an upper electrode, a middle electrode, a lower electrode and an insulating support. Its function is to eliminate the high-voltage electric field at the tip of the insulator and reduce or avoid corona loss and noise.
How does corona ring for insulator work?
Corona rings are usually made up of aluminum material. Corona rings are used in power transmission and distribution lines to protect insulators from the damaging effect of corona discharge. Corona is an electrical discharge brought about by ionization of air surrounding a conductor that is electrically energized.
Corona discharge can cause severe problems for high voltage transmission and distribution systems. It results in dielectric breakdown of insulating materials, loss of power and in some cases fire due to insulation failure.
These are designed in such a way that they create a strong electric field at their tips, thus causing complete ionization of air. This leads to uniform erosion of corona ring material due to corona discharges instead of concentrated erosion at specific points as on un-ringed insulators.
What are the advantages of corona rings for insulators?
Corona rings are used with proportion to the line voltage, creepage distance and pollution degree.
Corona rings have many advantages as compared to other products in the same field. The most important advantage is that they provide good electrical insulation between different phases in substations.
They help in preventing the accidental contact between live parts and grounded metal structures, thereby maintaining safety of operators. They can also protect cables from short circuit by providing a path for current leakage and subsequent tripping of circuit breakers.
Corona rings provide excellent resistance to high temperatures and mechanical stresses. They can be used under all weather conditions, including snow and ice storms.
Corona rings are used on high voltage insulators to prevent corona discharge.
The advantages of corona rings for insulators are:
- Reduces the leakage current and improve the pollution performance of insulator
- Reduce the electric field strength at the tip of insulator, preventing partial discharge
- Reduce electromagnetic radiation from transmission lines and reduce interference from other equipment
What are the types of corona ring for insulator?
The corona ring is a component of electrical insulators that is used to suppress corona discharge and arcing.
The corona ring is made up of the following parts: Upper base, lower base, silicone rubber ring and copper wire.
The upper and lower bases of the corona ring are made by die casting or pressure casting with high-strength alloy aluminum materials. The upper base has a protruding part for fastening and connecting with the upper pole of the insulator, and the lower base has a groove for fastening and locking with the insulator’s lower pole.
The shape, dimension and technical requirements for the corona rings for different types of insulators are supplied by Highv factory.
How to install corona ring on insulator?
- The insulator shall be cleaned with clean water, and the surface dust should not be remaining.
- Put the corona ring on the surface of insulator with the mark side upward, then align the screw holes and press it to make sure there is no gap between them.
- Drill holes in the insulator as per position of bolts to fit the corona ring, drill depth of which shall not less than 3mm (1/8”).
- Tighten screws with torque wrench in sequence as shown in figure, tightening torque for M12 is 50Nm, for M16 is 70Nm.
- Before installation of corona ring on insulator, please make sure whether the surface of insulator has any scratches or damage on silicone rubber, if it does, please take measures to protect the surface with tape etc., so as to avoid any problems during assembly of corona ring on insulator or during operation after installation.
How does the diameter of a corona ring for an insulator affect its performance?
When using corona rings, the size of the ring is important.
The diameter of the ring is usually determined to place the point discharge within a specified region of the insulator surface.
The diameter of a corona ring has an effect on its performance.
For example, the larger the ring, the larger the potential difference between the wires and the ring, and so the easier it is to get a given current flowing. But there’s a trade-off. The larger the ring, the harder it is to protect it against mechanical damage.
Corona rings are used on transmission lines to prevent electrical breakdown of the insulators supporting conductors. Under normal atmospheric conditions, insulators need not be protected from breakdown because air at those levels is an excellent insulator.
However, under severe conditions (heavy fog, heavy ice buildup on conductor or insulator), electrical breakdown can occur as water droplets bridge across insulators and conductors.
Corona rings are mounted on top of each insulator string and connected to ground with a resistor in series to limit fault currents.
The rings are subjected to high voltages (as much as 1/4 of transmission line voltage) and must be designed carefully so that they will withstand these voltages without arcing or corona discharge.
The larger diameter of a corona ring makes it easier to get a current flowing through it (and thence through any water droplets).
This means that you need less potential difference across your insulator.
Where can I buy the best corona ring for insulator?
Every aluminum corona rings factory saying that they are the best has sort of becoming a cliché. You could find many corona rings manufacturers that say that their methods make them the best supplier there is.
Technically, we are discussing the exact same thing now.
We’re about to say that we are the masters when it comes to designing and manufacturing aluminum corona rings for many advanced companies. What’s more, we have some viable reasons that prove this fact and back up our claim.
At Highv, we help you in all corona rings for insulator design and production from China.
Contact us now to get the quote about all corona rings for your insulator project.