Top 10 Transformer Accessories Every Power Project Needs in 2026: My Practical Procurement Guide

After years of working in power project procurement, I’ve noticed a very common mistake:

Many teams focus heavily on the transformer itself while overlooking the accessories. However, in real-world operation and maintenance, many transformer failures are actually caused by poor accessory selection, low product quality, or inadequate maintenance.

As renewable energy projects continue to grow and power grid upgrades accelerate, transformer operating environments are becoming increasingly demanding:

• High temperature and humidity in solar power plants
• Load fluctuations in energy storage systems
• Heavy-duty operation in urban distribution networks

All of these place much higher reliability requirements on transformer accessories.

In this article, I’d like to share my practical procurement experience and discuss the 10 most important transformer accessories for power projects in 2026.

Why Transformer Accessories Are the Real “Lifeline”

When I first entered this industry, I also believed that as long as the transformer itself was reliable, everything would be fine.

But after experiencing several power outages, I realized something important:

The transformer body is the skeleton, but the accessories are the nervous system.

Although small in size, these accessories are responsible for:

• Temperature, pressure, and oil level monitoring
• Insulation, moisture protection, and safety protection
• Voltage regulation and cooling
• Fault warning and risk prevention

Especially in:

• Solar power plants
• Energy storage projects
• Industrial substations
• Urban distribution systems

the quality of accessories directly impacts operational safety and maintenance costs.

1. Transformer Bushing

Transformer bushings are one of the most important insulation components.

Their role is to safely allow conductors to pass through grounded transformer tanks.

Over the years, I’ve seen many failures in coastal and polluted environments, including:

• Cracking
• Partial discharge
• Oil leakage
• Flashover accidents

My Procurement Advice

• Always verify voltage rating and creepage distance
• Ensure compliance with IEC / ANSI standards
• Use epoxy resin bushings for humid or polluted areas
• Composite bushings are ideal for renewable energy projects

Cheap porcelain bushings may reduce upfront costs, but they often create higher failure risks later.

2. Silica Gel Breather

Transformers constantly “breathe” during operation, and moisture in the air is one of the biggest threats to insulation oil.

In many cases, insulation aging is actually caused by moisture contamination.

This is especially serious in:

• Southeast Asia
• Coastal Africa
• Tropical environments

Procurement Tips

• Don’t judge only by silica gel color
• Sealing performance is more important
• Oil cups should be corrosion-resistant
• Self-regenerating or maintenance-free breathers are highly recommended

Many modern projects also use smart humidity monitoring systems.

3. Buchholz Relay

For oil-immersed transformers, the Buchholz relay is one of the most important protection devices.

It can detect gas generated by:

• Inter-turn short circuits
• Insulation breakdown
• Core overheating
• Internal arcing

before catastrophic failure occurs.

Installation Advice

It must be installed between:

• Main tank
• Conservator tank

with correct positioning and sensitivity settings.

4. Oil Level Gauge

Abnormal oil level often indicates:

• Oil leakage
• Temperature issues
• Internal transformer problems

Traditional mechanical gauges often suffer from:

• Float sticking
• Pointer failure
• Seal leakage

Today, many projects are switching to:

• Magnetic oil level indicators
• Digital oil monitoring systems

for higher accuracy and remote monitoring capability.

5. Pressure Relief Device (PRD)

When internal transformer pressure rises abnormally, the PRD quickly releases pressure to prevent:

• Tank rupture
• Explosion
• Personnel injury

As renewable energy integration increases, pressure protection becomes increasingly important.

My Recommendation

• Choose fast-response models
• Use high-temperature and corrosion-resistant materials
• Prefer internationally certified products

Avoid low-cost non-standard products.

6. Transformer Thermometer

Temperature is one of the most important indicators of transformer health.

Particularly:

• Top oil temperature
• Winding temperature

directly affect transformer lifespan.

Modern substations increasingly use:

• Digital temperature controllers
• Remote monitoring systems
• SCADA integration

7. Tap Changer

Tap changers stabilize transformer output voltage.

Procurement Focus

For OLTC systems, pay close attention to:

• Contact material
• Mechanical reliability
• Expected service life

to avoid future carbonization or mechanical failure.

8. Transformer Cooling Fan

Cooling fans are especially important in:

• Solar booster stations
• Heavy industrial projects
• High-temperature regions

Current Industry Trend

EC Energy-Saving Fans

Compared with traditional fans:

• Lower energy consumption
• Longer lifespan
• Lower noise

Smart Temperature-Controlled Fans

These automatically adjust fan speed based on transformer temperature.

9. Transformer Radiator

Radiators are responsible for heat dissipation.

Common problems include:

• Corrosion
• Oil leakage
• Blocked oil circulation

Export Project Advice

• Use galvanized steel radiators
• Apply anti-corrosion coatings
• Ensure optimized oil channel design

especially for coastal environments.

10. Online Monitoring System

Traditional maintenance means:

“Fix it after failure.”

Online monitoring means:

“Predict problems before failure.”

Modern systems monitor:

• Temperature
• Gas generation
• Partial discharge
• Moisture
• Operating condition

in real time.

My Final Procurement Advice

• Always prioritize certified products
• Never focus only on low prices
• Match accessories to the project environment
• Choose suppliers with strong technical support
• Pay attention to smart and maintenance-free technologies

Many people see transformer accessories as secondary components.

But in real power projects, they are often the key to operational safety and long-term reliability.

I hope this practical procurement guide helps more industry professionals avoid common mistakes and choose truly reliable products.

Luoyang Datang Energy Technology Co., Ltd. is a high-tech enterprise integrating R&D, manufacturing, and supply of power equipment and renewable energy solutions. Specializing in transformers, new energy components, distribution cabinets, and inverters, we have expanded our portfolio to include solar power systems, energy storage solutions, and air source heat pumps. With technological innovation as our core, we focus on creating high-reliability and high-performance power and energy efficiency solutions to serve global customers. Through a strict quality control system and international standard certification, we continuously deliver excellent products that empower our customers to build safe, stable, and sustainable power systems.