Technical characteristics of dry - type transformers

1. Anti-short-circuit ability, low-voltage winding copper foil is the height of the high-reactance, low-voltage current according to the winding between the ampere-turn balance requirements match, high and low voltage winding short circuit caused by the axial force is almost zero.
2. Overload capacity, if the same capacity of the transformer load loss is equal, then the corresponding copper cross-sectional area will be larger, the volume increases, the amount of filler resin, so the thermal capacity of the winding large, farady transformer short- Overload capacity.
3. Good anti-cracking performance, dry-type transformers using filler-type resin and copper foil structure, insulation and copper conductor thermal expansion coefficient of the most similar to effectively prevent the coil cracking. In the arc under high temperature combustion, does not produce any toxic gases.
4. Low noise, the transformer to take some special structure and design, making the noise greatly reduced, the overall noise level than the national professional standard noise value of 10-13dB (A) or more.
5. Lightning impulse withstand ability, lightning impulse voltage along the winding of the initial distribution of dry-type transformer winding insulation damage.
6. Flame-retardant characteristics, the use of filler-type resin casting process is conducive to environmental protection, Amorphous Metal Distribution Transformer with maintenance-free, moisture protection, anti-heat, flame retardant and self-extinguishing characteristics.

Dry-type transformers have the advantage of low noise

Dry-type transformers need to have a low noise level, need to be compact and have a lower weight to minimize the use of space, can be used exclusively for production activities. In many countries, users and specifiers have switched to encapsulated and open-type dry-type transformers as their desired solution. In Europe, some manufacturers have offered cast resin technology using Class B or Class F insulation systems. Many of the regions in Asia, including China and South Korea, have adopted this technology from Europe. However, these 11kv dry type transformer in the use of a decade later, its inherent limitations are becoming more users are more concerned about the problem. Increasing overload, environmental protection material requirements and long-term reliability have become disadvantages of these lower temperature solutions. Strict requirements can lead to cracking of large pieces of resin and accelerate the aging of materials, which will be less than 10 years time premature failure.

Differential Protection of Dry - Type Transformer

For the prefabricated compact transformer device, the dry-type transformer differential protection is the main transformer protection is installed according to the principle of circulating current. Transformer differential protection is mainly used to protect two-winding or three-winding transformer windings within and lead to the phase of the occurrence of a variety of short-circuit fault, but also can be used to protect the transformer single-phase inter-turn short circuit fault.
25kva pole mounted transformer are installed on both sides of the winding transformer, the secondary side of which is connected according to the circulating current method, that is, if the same level side of both sides of the current transformer is toward the bus side, the same level terminal is connected, Between the two lines connected in parallel current relay. The current flowing through the relay coil is the secondary current difference of the current transformer on both sides, which means that the differential relay is connected to the differential circuit.

Transformer no-load operation

200kva electrical transformer no-load operation refers to the transformer primary winding access to power, the secondary winding open working conditions. In this case, the current in the primary winding is called the no-load current of the transformer. The no-load current generates a no-load magnetic field. In the main magnetic field (that is, cross-linked one or two windings of the magnetic field) under the action, the first and second winding will be induced in the electromotive force.

When the 50 kva pole mount transformer no-load operation, although the secondary side no power output, but the primary side is still part of the power from the grid to absorb the active power to compensate for the magnetic saturation, in the core caused by hysteresis loss and eddy current loss referred to iron consumption. The hysteresis loss depends on the frequency of the power supply and the area of ​​the hysteresis loop of the core material. The eddy current loss is proportional to the square of the maximum flux density and frequency. In addition there is no load current caused by copper consumption. For different capacity of the transformer, no-load current and no-load loss size is different.

The automatic voltage booster is used to regulate the voltage

Power Engineers is known for reliability and continuous improvement in the field of rolling contact type automatic voltage controller, servo voltage controller, automatic voltage stabilizer, chemical process rectifiers, electroplating power rectifiers and special purpose transformers. The systems are designed and supervised by a team of qualified engineers having more than 35 years of experience to achieve best possible quality and total customer's satisfaction.
The automatic voltage booster

is used to regulate the voltage. It takes the fluctuate voltage and changes them into a constant voltage. The fluctuation in the voltage mainly occurs due to the variation in load on the supply system. The variation in voltage damages the equipment of the power system.

Special designs power transformers

When the transmitted power exceeds around 10 MVA, special designs are required to cope with the mechanical forces of short circuit currents, higher insulation levels and increased cooling requirements. For these ratings, liquid-filled farady transformers

 are usually used. The insulation between the windings becomes more and more demanding at Farady high voltage auto load booster Furthermore, resonance effects inside the winding itself have to be considered to avoid insulation failures during highly dynamic impulse stresses such as lightning strikes which may reach amplitudes of one to two thousands kilovolt with a 1 μs rise time.

Power Engineers is known for reliability and continuous improvement in the field of rolling contact type automatic voltage controller

Power Engineers is known for reliability and continuous improvement in the field of rolling contact type automatic voltage controller, automatic voltage booster,automatic voltage stabilizer, chemical process rectifiers, electroplating power rectifiers and special purpose transformers. The systems are designed and supervised by a team of qualified engineers having more than 35 years of experience to achieve best possible quality and total customer's satisfaction.

achieve best possible quality and total customer's satisfaction.

Power Engineers is known for reliability and continuous improvement in the field of rolling contact type automatic voltage booster, servo voltage controller,
single phase step voltage regulator

, chemical process rectifiers, electroplating power rectifiers and special purpose transformers. The systems are designed and supervised by a team of qualified engineers having more than 35 years of experience to achieve best possible quality and total customer's satisfaction.

The basic working principle of power transformer accessories

The principle of pole mounted transformer accessories: When a sinusoidal communication voltage U1 added to the primary coil at both ends, the conductor in the alternating current I1 and the occurrence of alternating magnetic flux ф1, which along the core through the primary and secondary coil form closed Magnetic circuit. In the secondary coil inductive mutual induction potential U2, together ф1 will also be induced in the primary coil of a self-inductance potential E1, E1 and the direction of the voltage U1 opposite the direction of the ups and downs, and then bound the size of I1. In order to adhere to the existence of flux ф1 need to have a certain power consumption, and the 37.5kva transformer itself has some loss, although at the moment no secondary load, the primary coil is still a certain current, the current we call "no-load current" . If secondary load connected to the secondary coil current I2 occurs, and therefore magnetic flux ф2, ф2 and ф1 opposite direction, played a mutual canceling effect, so that the total core magnetic flux has been reduced, and then make The primary self-inductance voltage E1 cut, the results of the I1 increases, showing the primary current and secondary load are closely related. When the secondary load current increases when I1, ф1 also added, and ф1 added some happened to be offset by ф2 that some magnetic flux, to maintain the core of the total magnetic flux unchanged. If you do not consider the loss of the transformer, can be considered an ideal secondary transformer power consumption is the primary power from the power to obtain power. Transformer can be modified according to the need to change the number of secondary coil winding number of secondary voltage, but can not change the power consumption to allow the load.

Cause Analysis of Transverse Leakage Reactance of Power Transformer

pole mounted transformer In concentric windings, for many reasons, such as voltage regulation or design, etc., may cause the actual height of the low or high voltage windings to return, specifically, whether low or high voltage or medium voltage Windings, their different levels of voltage required by the insulation level will be different, in order to ensure that the transformer in all aspects to achieve the best condition, we must be local conditions, targeted design and production, so to ensure its accuracy. Therefore, in practice, the transformer is generally not possible at the same height on the different voltage transformer winding turns are equal, then the excess number of turns to produce transverse flux, and these transverse flux in the concentric winding In the formation of lateral leakage reactance. Transverse leakage reactance is different from the Amorphous Metal Distribution Transformer winding corresponding to the number of ampere turns of the difference, that is, unbalanced ampere turns produced, the smaller the number of unbalanced turns, then the lateral leakage reactance is also smaller, if the number of turns To achieve a fully balanced state, then no lateral leakage reactance will be produced. Finally, we calculated by the formula, you can get all the short-circuit transformer reactance value, we can according to the results obtained to determine the transformer reactance value is not in line with national standards or international standards.

Why do the transformer winding leakage current test

Winding leakage current test purpose DC leakage test voltage is generally higher than the megger voltage, and can be adjusted, so it is more effective than the megger found defects, can be sensitive to reflect the porcelain insulation cracks, interlayer insulation Internal moisture and local loose fracture of insulating oil degradation, insulation along the surface of carbonization.
The polemounted transformer core and other accessories are in the electric field around the winding, if not grounded, the core and other accessories must sense a certain voltage, under the action of the applied voltage, when the induced voltage exceeds the discharge voltage to ground, Will produce discharge phenomenon. In order to avoid the internal discharge of the 37.5kva transformer, so the core ground.

Dry - type transformers should meet the technical requirements

Power transformers and pole mounted transformers, oil-immersed transformers are all three of the more common in the transformer, is also the main operation of the three major electrical products, the following by the power transformer factory - Device requirements. For fuse protection of transformers, the performance of the fuses must meet the system short-circuit capacity, sensitivity and selectivity requirements. oil immersed distribution transformer fitted with gas relays shall be installed with an elevated slope of 1% to 1.5% in the direction of the gas relays.

A Method to Reduce the Disturbance of Transformer to Amplifier

dry power transformers can be through the magnetic field, electromagnetic induction and the circuit to form interference amplifier is the biggest noise source in the audio machine. Therefore, to deal with its working condition and application environment, in order to effectively avoid the interference generated by the power transformer, the amplifier get excellent sound. Here I will discuss this with you.
Power transformer in addition to the amplifier power supply, but also to the amplifier and power coupled to the power grid in the interference source into the amplifier, but also the amplifier voltage and current changes reflected in the grid. In order to cut off the electrostatic field between the winding and capacitive coupling, isolation and common mode suppression of the resulting interference, to avoid the grid or circuit in the common-mode voltage coupling to the secondary or primary to the audio single phase step down transformer windings Faraday electrostatic shielding is critical. The shielding can be interlayer copper foil, can also be a complete co-shaped structure, in short, on the winding (especially for the primary winding) the more surrounded the better common mode rejection.

Distribution transformer capacity how to choose

At present, in the operation of distribution transformers, there are cases of under-load operation due to excessive capacity, and overheating or even burn-out due to overload or over-current operation. This kind of device capacity choice improperly, has affected the power system power supply reliability and the economy.
step voltage regulators capacity is selected on the basis of load statistics. Since the load is not expected to be readily available, the maximum expected load is chosen. This election results, often set the capacity is too large, the power system to bring adverse effects. If the choice of economic operation, is the use of transformer copper loss and iron loss equal conditions, derive the maximum economic load factor Amorphous Core Transformer and the transformer rated capacity and maximum load ratio. As the actual operating load is not necessarily the maximum load load statistics, and the load is random, operating efficiency is variable, and its economic operating efficiency is difficult to achieve.

The basic composition of the transformer

three phase pad mounted transformer components include the body (core, winding, insulation, lead), transformer oil, fuel tank and cooling devices, pressure regulator, protection devices (moisture, airway, gas relays, oil conservator and temperature measurement devices ) And outlet bushing.
1, core
Core is the main part of the transformer in the magnetic circuit. Usually by the high silicon content, thickness 0.35mm \ 0.3mm \ 0.27mm, coated with insulating paint by the surface of hot-rolled or cold-rolled silicon steel sheet laminated together.
Core is divided into two parts of the core column and the cross-section, the core column sets a winding; transverse magnetic circuit is used.
Core structure of the basic form of heart-and shell-type two.
2, winding
Winding is the circuit part of the Amorphous Metal Distribution Transformer, which is insulated with double-wire package or round wire wrapped around the enameled wire.

With the rapid development of China's national economy, the demand for electricity has become increasingly long, as the main equipment in the power transmission system - the transformer has also been considerable development. In order to meet and meet the market demand, many manufacturers to continuously improve the product structure, improve product performance from abroad to introduce advanced production technology and equipment, new technology in the exploration of new materials to make unremitting efforts.
The development of 13.8kv single phase transformer manufacturing process mainly combines the characteristics of new products and new structure to develop a corresponding process, and focus on new materials and new equipment development and application to continuously improve product quality and reliability, but the research and development of these new processes Need a lot of bonuses and production costs increase, and the current transformer oversupply, price competition is extremely fierce, the user in the bidding activities in the preferred conditions is the price factor, it is difficult for manufacturers to invest a lot, so the production process to Can not be developed, the quality of products do not increase, the quality does not increase, the price will not be high, there is no profit resulting in a vicious circle.
China's future development direction of the 11kv single phase transformer is still energy-saving, low noise and fire and explosion-proof, high reliability development, so some of the above talk about the process should continue to promote universal use. Another choice of high-quality low-loss magnetic materials, large-scale products can be used laser irradiation or slotted silicon steel sheet, with the axial amplitude of the compaction device winding machine, vapor drying equipment, step-type cross-cutting line and other advanced production equipment Popular use. Insulation material processing as much as possible by a unified professional manufacturers to gradually increase the emerging solid insulation materials such as injection molded parts, foreign insulation parts processing with laser cutting, China may also develop a light processing insulation pieces. In addition, the pressure on the quality should be a great effort to be studied, such as fuel tank surface treatment, the type of paint so that the tank as beautiful as possible from: industrial variable electrical appliances.

Precautions on Stripping of Power Transformer Coil

1, the 100kva distribution transformer coil stripping prohibit blowing with a fan blowing body, to prevent the impact of frigidity quenching.
2, demolition of power transformer mold can not use dirty gloves to help form removal. Because the coil temperature is higher than 100 ℃, the winding has not been completely cured successfully, dirty contact coil easily left spots, affecting the appearance of the coil and found the end of the transformer coil has a long strip of non-curing phenomenon, do not touch, do not clear .
3, the panel fastening screw due to pouring material into the hard and difficult to remove after the invasion, not hard to remove, to prevent the screw fracture.
4, be sure to clean up all the material inside the copper mouth, to avoid affecting the transformer test, misdiagnosed as coil turns deviation, DC resistance unbalanced or broken head failure.
5, remove the single phase step voltage regulators die when not pull hard pull, at the same time to check the coil surface is defective. There are parts of the defect immediately check the corresponding parts of the outer mold and be dealt with to avoid the next re-emergence of a similar situation.

Farady automatic voltage regulators

Farady has different types of step voltage regulators, common names for each type will be identified and used interchangeably along with generic names, such as automatic voltage booster and automatic voltage regulator. Please note that the descriptions, operational explanations and other commentary provided about the different types of AVRs is for informational purposes only and is intended to provide an overview of variations among a class of products generically called “automatic voltage regulators.”

Farady high voltage auto load booster

Applied in the utility’s distribution systems are generally medium-voltage mechanical high voltage auto load booster(SVR). For distribution transformers, China already has a 110kV, 220kV, 330kV and 500kV high voltage, EHV transformer production capacity. For load EHV generated, Farady high voltage auto load booster can reduce the loss of distribution through regulate the voltage to work condition, for those utility and end user who use farady high voltage auto booster already prove can increase power supply company income Three phase automatic voltage booster regulate three phase in one time, save cost and easy maintain, fast installment.

Compact Substation

Prefabricated compact transformer doors are screwed with double point closing device with flush mounted handles for pad loadings and the compact substation is designed for outdoor/indoor type as per customers’specific requirement. Our range of Compact Substation is manufactured using quality material and latest manufacturing technologies. We can manufacture bulk orders of this product in a short span of time. These stations are high in demand as these are flawless and manufactured using high quality machines and other required raw material, sourced from the prestigious vendors of the industry.

Farady Dry Type Transformer

With high-tech infrastructure facilities, we are offering a large spectrum of Dry Type power transformer. These Farady transformers are developed under the stringent supervision of our highly trained professionals that confirms their high durability and long life. Dry Type Transformers are for indoor and outdoor applications in schools, hospitals, industrial plants, commercial buildings and anywhere that safe and dependable power are important considerations. Further, these are used in numerous industries and are quality tested on various parameters before they are dispatched to our patrons.

Distribution Transformers Feature

Farady offers several oil immersed distribution transformers. Our general purpose distribution transformers are available in open core and coil, copper wound, and totally enclosed, non-ventilated designs. We provide single and three phase indoor and outdoor models. Low temperature rise models and specialized transformers are designed to withstand the harmonic currents of non-linear loads without experiencing voltage instability or overheating.

Farady 3-Phase transformer

We generally manufacture Farady transformers with two winding sections to give us the best possible electrical safety. The 3 phase step up transformers are designed for temperature class F or H to minimize the weight. The transformer's protective structure is made of H class insulation materials with built-in air channels making it possible to have very powerful cooling if the device can be equipped with forced air circulation.

Farady padmount transformer

Padmounted transformers are green, metal utility boxes mounted on slabs of concrete near many homes and businesses. This equipment, which provides power for you and your neighbors, sits on an easement that allows Farady to perform necessary maintenance work on it. Three phase pad mounted transformer are made in power ratings from around 75 padmount transformer to around 5000 kVA pad-mounted transformer and often include built-in fuses and switches. there phase pad mounted transformer Primary power cables may be connected with elbow connectors, which can be operated when energized using a hot stick and allows for flexibility in repair and maintenance.

Farady Distribution & Pad-Mounted Transformers

Three phase pad mounted transformers from Farady are designed to protect against environmental hazards and offer excellent mechanical strength, proven through years of service and special testing. Available in live-front or dead-front designs, both our radial and loop feed configurations are built according to ANSI standards. Our high-quality corrugated style radiator offers excellent cooling with an aesthetically-pleasing exterior.Like all power transformers from Farady, our distribution and pad-mounted transformers are developed and produced to each customer's exact specifications. We strive to provide the most innovative power transformers at a competitive price.

Amorphous alloy Distribution Transformer

Amorphous Metal Distribution Transformer uses new magnetic material , amorphous alloy, as core. The no-load losses dropped about 75% and no-load current declined about 80% compared with traditional silicon steel amorphous Core Transformer. This reduces the running cost of the transformer greatly. It’s an ideal distribution transformer and particularly suitable for low load rate areas such as countries, developing areas and having a great real meaning in building saving recourse society.

Farady Pad-Mounted Transformer

A transformer is a device that reduces the high level voltage found on Farady distribution transformer system, to the more useable voltage levels found inside homes and businesses. A pad-mounted transformer is the underground equivalent of the overhead transformer. In residential areas they look like forest green colored boxes.  All cables come into the transformer below ground, and all connections are made inside and kept out of view.

Description of Automatic step voltage regulator Controller

The auto load booster stabiliser can operate with input and output voltages different from the rated voltage. Such setting can be performed at the factory or at the Customer's premises by adjusting the dip-switch mounted on the electronic control card within the allowed range and according to the instructions described in the handbook. In our single phase step voltage regulator we are using heavy section of electrolytic grade rectangular copper strip instead of copper wire to minimize the losses & increase the efficiency of equipment. We are also using self lubricating carbon roller assemblies instead of ordinary carbon brushes which offer more reliability and trouble free performance of the equipment.

Voltage regulator booster transformer

The step voltage regulator consists of an autotransformer with continuously variable transformer ratio. The voltage intake varies depending on the contact position; therefore the voltage supplied to the transformer primary winding also varies. The voltage across the regulator contacts (and consequently that on the secondary winding of the high voltage auto load booster transformer) is either in phase or in opposition to the supply voltage, and it is therefore added or subtracted to the supply voltage, thus compensating its variations.

SCB 10 Cast Resin Dry Type Transformer

SCB 10 Cast Resin Dry Type Transformer

Farady Electric manufacture a complete range of three phase distribution transformers, including oil-immersed type & cast resin dry-type transformer, we always designed with increased margins of safety and reliablity,and meet the following standard:

IEC60076, IEEE Std, GB1094

http://www.farady-electric.com/scb10/

The automatic voltage stabilizer with a load

The automatic voltage stabilizer can operate with a load variation range from 0 to 100%, the response time depends on the input voltage percentage variation and on the type of design. The automatic voltage booster stabiliser is not affected by the load power factor and since regulation is performed without chopping the voltage sine wave, neither appreciable harmonic distortion nor phase displacement is introduced on the downstream line. The equipment is housed in a metal enclosure, depending on the type, the stabilisers can be air-cooled (natural or aided convection) or oil-cooled.

Description of Auto Voltage Stabilisers

The auto voltage stabilizer system is designed to operate with rated voltage in accordance and is expected to be connected between main power supply and load.
The purpose is to supply the loads a stabilised voltage having an input voltage variable with respect to the rated value. The highest input current is obtained with the minimum rated voltage; as the output voltage is stabilised within a close range, the output current is considered to be constant. This auto load booster takes place on the ‘rms’ value of the voltage and is not affected by harmonic distortion in the mains.

Gilled Radiator Dtep Up Transformer

Gilled Radiator Dtep Up Transformer

Farady offers a complete range of distribution transformers designed to grant the reliability, durability, and efficiency required in utility, industrial, and commercial applications. Farady’s liquid filled transformers are manufactured in accordance with the most demanding industry and international standards.

http://www.farady-electric.com/gilled-radiator-step-up-transformer/