State Grid Corporation of China Verified SupplierOne-Stop Supply of Conventional & Solar Power Equipment

QDTB® TransformerQuality & Dependability, Trust Builder

QDTB Electrical Systems - High Voltage Power Equipment Manufacturing

Design Your Complete Electrical System Online

From transformers and switchgear to energy storage and EV charging — configure your full power system online, generate a complete equipment list with FOB pricing, and get it delivered by QDTB engineers.

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ISO 9001 / 14001 / 45001CE · IEC · IEEE · GB25+ Years · 100,000 m²Export to 30+ Countries

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Complete power equipment solutions for generation, transmission, distribution, and utilization

Power Transmission & Distribution

Transformers, switchgear, substations and reactive compensation for power transmission and distribution networks.

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Oil-Immersed Transformers

S11/S13/S20 series oil-immersed distribution transformers

Dry-Type Transformers

SCB series cast resin dry-type transformers

Amorphous Alloy Transformers

SBH15/SBH21 series amorphous alloy core transformers

Box-Type Substations

ZBW series European prefabricated substations

American Pad-Mounted Transformers

ZGS series American pad-mounted transformer substations

High Voltage Switchgear

KYN/XGN series high voltage switchgear

Low Voltage Switchgear

GGD/GCS/GCK/MNS series low voltage switchgear

Ring Main Units (RMU)

Integrated primary and secondary ring main units

Cable Branch Boxes & Switching Stations

DFPW series cable branch boxes and switching stations

Reactors

CKSC/BKSC series dry-type iron core reactors

Power Capacitors

Power factor correction capacitors for energy efficiency

Busway (Bus Duct)

Low-voltage and medium-voltage busway (bus duct) systems for high-current power distribution in data centers, industrial plants and commercial buildings.

Pole-Mounted Switchgear

Outdoor pole-mounted vacuum circuit breakers and primary-secondary fusion distribution automation equipment

SVG & SVC Static Var Compensation

Static Var Generator (SVG) and Static Var Compensator (SVC) systems for dynamic reactive power compensation, power factor correction and voltage stabilization in 10 kV and 35 kV power networks.

Active Harmonic Filters

Active Power Filters (APF) for harmonic mitigation and power quality improvement in industrial and commercial power distribution systems, reducing total harmonic distortion (THDi) at the point of common coupling.

SCADA & Secondary Automation

Protection IEDs, DC panels, SCADA stations, communication and metering equipment for MV/LV substation and distribution systems. IEC 61850 / IEC 60870-5-104.

Why Choose QDTB® Transformer

QDTB® Transformers is a one-stop supplier of conventional and solar power equipment, providing power distribution system design, transformers, switchgear, substations and solar systems for projects worldwide. With over 25 years of experience, we operate a 100,000㎡ modern production facility equipped with advanced CNC machinery and automated production lines. Our commitment to quality is reflected in our ISO 9001/14001/45001 certifications and 99.8% quality pass rate. We serve customers in over 30 countries across Southeast Asia, Europe, Africa, and South America, providing reliable power equipment solutions for diverse applications.

Learn More About Us

25+

Years Experience

100K

m² Facility

500+

Employees

99.8%

Quality Pass Rate

🛡️

China State Grid Supplier

Qualified supplier to State Grid Corporation of China

✅

China Electrical Industry Association Member

Member of the China Electrical Industry Association

🏅

Nationally Certified High and New Technology Enterprise

Recognized as a national high and new technology enterprise

Tech Hub — Engineering Insights

Selection guides, technical comparisons and industry knowledge for power equipment buyers

Distribution Transformer Price Breakdown 2026: What a 100–2,000 kVA Transformer Really Costs (FOB Qingdao)

Real 2026 FOB Qingdao reference prices for oil-immersed S13-M and dry-type SCB13 distribution transformers from 100 to 2,000 kVA, with the copper-link mechanism explained so you can compare quotes fairly.

Distribution Transformer Selection & Price Guide 2026

Standard S13-M oil-immersed and SCB13 dry-type distribution transformers with full model numbers, descriptions and FOB Qingdao reference prices — computed from the anchored LME copper price ($14,185/ton, 2026-08-23).

FOB Quotation Breakdown: From Ex-Works Price to Qingdao Port — What Are You Really Paying For?

What a Chinese transformer supplier's FOB Qingdao quotation actually contains: copper-linked materials, manufacturing, testing, export packing, inland haulage and margin — with real 2026 price tables and a fair-comparison checklist.

Stop Comparing Initial Prices: How to Calculate Transformer Total Cost of Ownership (TCO)

The cheapest transformer is rarely the cheapest in the long run. A step-by-step TCO model covering purchase price, no-load and load losses, maintenance and lifetime — with real numbers showing why 20-year loss costs dwarf the invoice.

How to Size a Distribution System: Transformer, Switchgear and Feeders in One Calculation

Sizing the transformer is only one third of the job. The transformer's impedance sets the short-circuit current; the short-circuit current sets the breaker ratings and cable sizes; those set the protection settings. Follow one 800 kVA project through the full chain — load list, transformer, short-circuit current, switchgear, feeders and protection coordination — with real 2026 FOB prices and ready-to-use formulas.

How to Choose the Right Voltage Class: 6/10/11/20/33 kV for Distribution Transformers

Distribution transformers come in 6, 10, 11, 20 and 33 kV primary classes. A practical guide to matching voltage class to your grid, load size, distance and equipment — with the tap-range factor that buyers often miss.

Waste-to-Energy Plant Transformer: How to Size the GSU and Auxiliary Units, Why HCl Flue Gas Drives the Corrosion Specification, and What VFD Harmonics Do to the Winding

A waste-to-energy plant needs a GSU at 1.05–1.10× generator MVA, an auxiliary transformer at 12–22% of gross output and a station transformer for start-up — sized from generator MVA, never from tonnes per day. This guide covers HCl and ammonia-slip corrosion (ISO 12944 C5/CX), 45–55 °C derating, K-factor selection for VFD fans and ACCs, grid-code protection, test scope, and indicative 2026 price bands with loss capitalisation at 7,500 operating hours a year.

Geothermal Power Plant Step-Up Transformer: How to Size a GSU for Flash and Binary Units, Why H2S and 45 °C Powerhouse Air Change the Specification, and What Load Rejection Demands

A geothermal GSU is sized on generator MVA (1.05–1.10×, 8–12% impedance at 33 kV), not plant MW, while the house load decides the auxiliary transformer: 8–18% of gross for flash plants and 15–30% for air-cooled binary ORC. This guide covers sizing, H2S corrosion specification, 45–50 °C derating, altitude, seismic and load rejection, plus indicative 2026 price bands and loss capitalisation at 8,000 operating hours a year.

District Heating & CHP Transformer: How to Size a Heat-Network Substation, Why the Pump Load and the Summer Minimum Set the Rating, and What Makes a CHP Step-Up Transformer Different

A district heating transformer is sized by its pumps, not its MW: a 10 MW heat substation needs only 160-250 kVA, while a 25-50 MW CHP generator needs a 40-75 MVA step-up unit. This guide covers the five-step hydraulic-to-electrical sizing calculation, the summer-minimum no-load loss trap, temperature difference as the lever that cuts pumping energy, dry-type versus oil for basement substations, ventilation and noise limits, CHP power-to-heat ratios and tap ranges, heat pump and VFD harmonic duty, and indicative 2026 FOB prices.

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Global Operations in Real Time

Power equipment operating across our worldwide delivery network

33.0MVA

Distribution Capacity

Regions shown reflect our actual business coverage. Figures are illustrative data from the QDTB digital O&M demo environment with simulated telemetry — showcasing monitoring capability.

Quality & Dependability, Trust Builder

QDTB is a registered trademark of Shandong Yaqing Electrical Technology Co., Ltd. and a member of the State Grid of China supplier pool and a member of the China Electrical Industry Association.

Our service areas include power transmission & distribution, PV-ESS-EV charging, wind power, urban power grid, IDC data centers, heavy industry (oilfields, petrochemical plants, mines, etc.) and EPC projects.

We firmly believe transparent pricing is the first step to sincere service.

Frequently Asked Questions

Common questions about our system design service, what we supply, and how projects are delivered

Are you a manufacturer or a trading company?

We are a manufacturer. QDTB is a registered brand of Shandong Yaqing Electrical Technology Co., Ltd. — 25+ years in business, a 100,000 m² production base in Qingdao, and our own in-house engineering team. We manufacture transformers, switchgear and prefabricated substations ourselves, and integrate third-party equipment such as inverters, batteries and EV chargers into complete systems under our own quality and test procedures. We also build to customer specifications, including private labelling and local standards adaptation.

What exactly is included in a complete electrical system from QDTB?

A complete system typically includes: system design and single-line diagram; load analysis and equipment sizing calculations; the full equipment list (transformers, MV/LV switchgear, protection, power factor correction, energy storage, EV charging and cabling); construction drawings; factory acceptance test (FAT) procedures; export packing and shipment to your port; commissioning guidance; and the full documentation package. You can take the whole scope or any part of it.

Do you supply single units or only complete systems?

Both. You can order a single transformer or substation, or a full configured system. The online configurator produces an equipment list that you can purchase as a whole or item by item. There is no minimum order quantity for standard catalogue products.

How does the online configurator work?

Choose your application scenario, enter your load and site conditions, and the configurator generates a single-line diagram, sizing calculations, construction drawings, a complete bill of materials and indicative pricing — in minutes, with no registration required. Each result can be shared with our engineers for review, and we confirm the final design before production.

What is the typical lead time for a complete power system?

Standard distribution equipment ships in 30-45 days. A complete configured system — transformer, switchgear, storage and charging equipment — typically takes 45-75 days from design freeze, including assembly, routine testing and export packing. Large-capacity or fully customised projects: 90-120 days. This remains significantly faster than many Western manufacturers, and rush orders can be accommodated for urgent projects.

How is a system priced?

Each configured system returns a complete equipment list with budgetary unit prices on an EXW / FOB Qingdao basis, so you can see the cost of every item and adjust the scope. For projects we issue a formal quotation that can include freight and insurance options (CIF / DAP), spare parts and commissioning.

What certifications do your products hold?

Our products are ISO 9001 / 14001 / 45001 certified, CE marked on selected models, and designed to meet IEC, IEEE and GB standards. Routine test certificates are issued with every unit, and third-party inspection (SGS, BV, Intertek and others) can be arranged on request.

Which applications do you cover?

We supply power systems for data centres, airports, hospitals, ports and terminals, mining sites, manufacturing plants, commercial and office buildings, utility-scale solar and wind farms, battery storage projects, microgrids and off-grid or remote power. Around 27 scenario templates are available in the configurator as a starting point.

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Run the numbers first, then send your inquiry — generate your equipment list and FOB price with our free calculators, and get a detailed quotation from our engineers within 24 hours.

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