Transformer Components Complete Guide

What is a transformer assembly?

Transformer components(Transformer Components / Accessories) is a collective term that refers to the transformer body (i.e., the active part consisting of the core, windings, and clamps, etc.), in addition to the transformer body, in order to achieve the transformer'sisolate,cool off,pressurize,safeguard,monitorsrespond in singingexternal linkA general term for a variety of separate equipment, devices and accessories installed for a range of auxiliary functions such as.

From a functional point of view, if the transformer body is the "heart", responsible for energy conversion, then the components are to maintain the heart beating "circulatory system", "respiratory system", "Nervous system" and "protective armor". They are to make the transformer can be from a static physical device, transformed into a can interact with the power grid, can self-regulation, and can be in the abnormal situation of self-protection of the dynamic system. The performance and reliability of the components directly determines the safety, availability and full life cycle cost of the transformer asset. A well-designed transformer body configured with poor quality or mismatchedTransformer accessoriesIf it is not, its overall performance will be greatly reduced, and may even lead to catastrophic accidents.

Transformer body and components

Understanding the interdependencies between the transformer body and components is critical:

• Transformer Active Part: This is the core of the transformer's function and is the physical basis for voltage transformation and energy transfer based on Faraday's law of electromagnetic induction. Its main components include:
  • Core: To form a magnetic circuit to direct and concentrate magnetic flux.
  • Windings: Forms an electrical circuit and is the vehicle for generating and inducing magnetic flux.
  • Leads: Divert the current from the winding.
  • Clamping Structure: Serves as a sturdy mechanical skeleton that holds the core and windings securely in place to withstand vibrations in transportation and large electrodynamic shocks in operation.
• Transformer Components:: These are auxiliary systems that support and guarantee the proper functioning of the ontology. Without the components, the ontology cannot function. Example:
  • not haveoil tankrespond in singinginsulating oilThe insulation distance and heat dissipation capacity of the windings in the air are far from sufficient to withstand the high voltage and operating heat, which will instantly breakdown and burn out.
  • not havetrocar, high voltage current cannot be safely drawn from a grounded tank and energy cannot be input or output.
  • not havecooling systemIf the transformer generates a huge amount of heat that cannot be dissipated, the temperature rise will quickly exceed the tolerance limit of the insulation material.
  • not haveprotection deviceIn the event of an internal failure, the fault energy will continue to be fed into the device, eventually leading to complete destruction or even explosion.

Thus, the body and the components are an organic whole that together determine the ultimate performance and reliability of a transformer.

What are the transformer components?

Transformer components can be divided in detail into the following main categories according to their function:

Cooling System Components

This is the core part responsible for transformer heat management.

Heat Sinks/Radiator (Radiators)

This is the most basic heat sink element. Hot oil enters from the upper part by thermosiphon effect (natural convection) and flows back to the tank from the lower part after cooling. According to the structure is divided intoChip Radiatorand corrugated walls of corrugated tanks.

Cooling Fans

typicallyAxial Fans, mounted on the side of the radiator. It is automatically started and stopped by the temperature controller according to the top oil temperature or winding temperature, and the cooling efficiency can be increased 30%-50% by forced air convection.

Oil Pumps

Installed in the piping between the main tank and the cooler for theForced oil circulation(OFAF/ODAF cooling method). For large power transformers, forced oil circulation can greatly improve the heat exchange efficiency and reduce the size of the cooler.

Insulation & Connection Components

Safeguard electrical isolation and secure connections inside and outside the transformer.

High/Low Voltage Bushings (HV/LV Bushings)

It is the key insulating part of the high voltage conductor through the wall of the grounding box. According to the structure is divided intoOil-Immersed Paper Capacitor Casing (OIP),Resin Impregnated Paper Capacitor Sleeves (RIP)etc. Its selection should strictly consider the voltage level, rated current, creepage ratio distance and mechanical strength.

Conservator Tank

An auxiliary tank mounted above the main oil tank. It provides compensation space for thermal expansion and contraction of the insulating oil and ensures that the main tank is always 100% filled with oil. Modernoil conservatorOften with internalrubber diaphragmor air bladder to completely isolate the oil from the air and prevent it from oxidizing and getting damp.

Dehumidifier/Breather

Installed in the air vent of the oil storage cabinet. Internally filledColor Changing SiliconeHighly efficient in absorbing moisture from the incoming air. The oil seal at the bottom is used to filter dust from the air.Intelligent Maintenance-free Moisture AbsorberInstead, a humidity sensor and a heating regeneration system are integrated for automatic operation.

Voltage Regulation Components

Responsible for adjusting the voltage ratio of the transformer according to the grid demand.

On-Load Tap Changer (OLTC)

The most complex and only moving internal component in a transformer. It allows the transformer to regulate the voltage by changing the winding taps without interrupting the supply. Its core consists of a selector switch and a toggle switch, which are activated by theMotor drive mechanismPerform the operation.

Off-Circuit Tap Changer (OCTC)

The structure is relatively simple and is usually mounted on the transformer cover or on the wall of the box by means of amanual operating handleMake adjustments. The transformer must be completely de-energized before adjustment.

Protection & Safety Components

Ensure that the transformer can be protected in time under abnormal working conditions.

Gas Relay/ Gas Relay / Buchholz Relay

Two levels of protection are realized through an internal two float/stall system. The upper float responds to slowly generated gas (light gas alarm) and the lower stall plate responds to the oil flow impact from a severe fault (heavy gas trip). It is the most direct and reliable way to determine internal transformer faults.Transformer protection relaysThe

pressure relief valve (Pressure Relief Device)

A spring loaded mechanical valve. In the event of an internal malfunction that causes a dramatic transient increase in tank pressure above the set point, it opens instantaneously, releasing the pressure quickly and preventing permanent deformation or bursting of the tank.

Monitoring & Measurement Components

Provide visual data on transformer status for operators.

oil level meter (Oil Level Gauge)

typicallyMagnetic Linkage Oil Level GaugeThe oil level in the reservoir is sensed by the float and driven to an external pointer indication. With high and low oil level alarm contact.

Dial Thermometer

Its temperature sensing package is inserted into the oil in the top layer of the transformer, measuring and indicating theTop oil temperature. Typically with 4 sets of adjustable contacts for controlling cooling fan start/stop, high temperature alarms, and ultra-high temperature trips.

Winding Temperature Indicator (WTI)

It not only measures the top oil temperature, but also simulates and calculates the temperature rise of the windings with respect to the oil by means of a built-in current transformer and a heating element, thus indicating theWinding hot spot temperature. Also with control and protection contacts.

Online Monitoring Systems

This is the core of transformer intelligence. Included:Dissolved gas in oil online monitoring (DGA),Online monitoring of casing dielectric loss and capacitance,Partial Discharge Online Monitoring (PD),On-line monitoring of microwateretc. These systems enable real-time assessment of transformer condition and early warning of faults.

How do I choose the right transformer assembly?

Selecting the right components is a systematic project that directly determines the final performance and reliability of the transformer.

1. Matching based on transformer specifications:: This is the basis. For example, a 500 MVA step-up transformer must be selected with high-speed switching capabilityVacuum type on-load tap-changerand with redundant oil pumps and fansForced oil circulation cooling systemA 500 kVA distribution transformer, on the other hand, may only need to be equipped with an unexcited on-load tap-changer and naturally cooled heat sinks. The rated voltage, current and mechanical properties of the components must match the design parameters of the transformer body.
2. Full consideration of the operating environment:: Environmental conditions are the key variable. In coastal areas with high salt spray (e.g. C5 corrosive environments), all outdoor components such as radiators, fan motors, control cabinets, etc. must be treated with special anti-corrosion treatments (e.g.hot dip galvanizing,Class C5 coating) and stainless steel fasteners. At high altitudes, due to the reduced air density, the cooling efficiency and the external insulation of the casing are reduced, and it is necessary to select a modified design of the cooler and a casing with a larger creepage ratio distance.
3. Clarify reliability and maintenance requirements:: For critical transformers powering data centers, hospitals or continuous production lines, reliability comes first. Top brand on-load tap-changers should be selected and equipped with comprehensiveTransformer online monitoring systemto realize the change from periodic maintenance to condition-predictive maintenance. For unattended substations, the choice ofIntelligent Maintenance-free Moisture Absorberand remotely controllable cooling systems can greatly reduce on-site O&M efforts.
4. Strict adherence to technical standards and specifications:: All components must be provided with type test certificates in accordance with international (e.g. IEC, IEEE) or national (e.g. GB) standards. The end-user's technical specification is the direct basis for selection and any deviation must be confirmed in writing. This ensures component compliance in terms of design, performance and safety.

How do I install the transformer assembly?

The quality of the installation of the components is the final guarantee that their function will be realized, and any negligence may lead to serious transformer failures in the future.

Strict adherence to manufacturer's installation guidelines

Each component, especially complex devices like on-load tap-changers and bushings, has its own unique installation procedures, torque requirements and precautions. They must be carefully read and understood before installation.

Ensure absolute cleanliness and dryness

This is the golden rule for the installation of insulated parts. When installing parts in contact with insulating oil such as bushings and oil conservators, all flange surfaces and seals must be wiped clean with a nonwoven cloth dipped in qualified transformer oil. It is strictly forbidden to perform open-box installation in rainy weather or high humidity to prevent moisture from intruding into the transformer body.

Correct torque and sealing process

All flange connection bolts must be tightened to the specified torque in steps in an alternating diagonal pattern using a calibrated torque wrench. Sealing washers must be correctly placed in the sealing grooves to ensure even pressure. This is essential to prevent oil leakage from the transformer.

Comprehensive functional checks and commissioning

Upon completion of the installation, a systematic functional test must be carried out. This includes: a full switching test of the manually and electrically operated on-load tap-changers and verification of the consistency of the remote and local position indications; a test of the logic of the automatic and manual control of the cooling system; a simulation test of the alarm and trip contacts of all protective devices (gas relays, pressure valves, thermometers, etc.); and a check of the correctness of the wiring in all secondary circuits and a test of the insulation resistance.

Construction by professionals

The installation of transformer components is a highly specialized task that must be performed by professionally trained and experienced technicians.

Why choose transformer components from Innotransformer?

INNOTD (Fuzhou) Sales Co. As a specialized supplier in the field of transformer components, we are committed to providing high-performance and high-reliability products and solutions to our global customers.

• comprehensive portfolio: We offer a wide range of products fromCooling Fans,protection deviceuntil (a time)Intelligent online monitoring systemWe offer a full range of transformer components for your one-stop shopping convenience.
• Technology leadership and innovation: We continue to invest in research and development, and our products have reached industry-leading levels in terms of intelligence, energy efficiency and reliability, especially ourTransformer thermostatrespond in singingIntegrated online monitoring solutions, which can significantly improve the efficiency of transformer operation and maintenance.
• Strict quality control: All products are manufactured under the ISO 9001 quality management system and pass strict factory tests to ensure that every piece ofTransformer AccessoriesAll meet the highest quality standards.
• Customized Solutions: We have a deep understanding of the unique needs of different clients and projects, and are able to provide specialized technical support andCustomized component solutionsto perfectly match your transformer design and operating requirements.
• Professional service support: Our expert team provides you with all-round support from selection consultation, technical program design to installation guidance and after-sales service to ensure the smooth implementation of your project.

Choosing Inotera is choosing reliability, efficiency and professionalism.

Contact our experts for customized transformer component solutions.