Views: 0 Author: Site Editor Publish Time: 2026-01-07 Origin: Site
Core: Made from laminated, high-permeability silicon steel, it forms the main magnetic flux path, minimizing energy loss.
Windings: These coils, typically of copper or aluminum with robust insulation, are concentrically arranged on the core. They create the circuits where voltage transformation via electromagnetic induction occurs.
Dielectric Insulating Oil: The vital medium that insulates live parts and transfers heat via natural or forced convection to the tank walls.
Tank: The sealed, robust outer container housing all internal parts and oil.
Conservator (Oil Expansion Tank): Compensates for oil volume changes with temperature, minimizing moisture absorption.
Radiators and Cooling Systems: Increase heat dissipation surface area. Forced Oil Forced Air (OFAF) cooling, commonly used in Zisheng's high-capacity units, employs pumps and fans for maximum efficiency.
Protective Devices: Key safety components include Pressure Relief Devices to prevent tank rupture and Buchholz Relays to detect internal faults by sensing gas accumulation.
Bushings: Provide the insulated electrical connection between internal windings and the external grid.
Step-Up Transformers: Increase voltage at generation points (e.g., power plant outlets) for efficient long-distance transmission.
Step-Down Transformers: Reduce voltage at various substation levels within the grid.
Distribution Transformers: Final voltage reduction for end-user consumption (e.g., to 400V) in factories, commercial buildings, and residential areas.
ONAN (Oil Natural Air Natural): Relies on natural oil convection and air radiation. Common for mid-range capacities.
OFAF (Oil Forced Air Forced): Uses oil pumps and fans for enhanced cooling, ideal for high-capacity and Zisheng's heavy-duty industrial transformers.
Three-Phase Transformers: The standard for power generation, transmission, and industrial use.
Single-Phase Transformers: Often used in rural distribution or for specific residential applications.
Power Generation: Essential in thermal, hydro, wind, and solar farms for step-up and grid connection.
Transmission & Distribution (T&D) Networks: The workhorse of substations at all voltage levels.
Heavy Industry: Provides reliable power for mining, steel mills, chemical plants, and large manufacturing facilities.
Major Infrastructure: Powers data centers, hospitals, airports, and rail networks.
Superior Heat Dissipation & Overload Capacity: The oil's high thermal capacity allows for better short-term overload tolerance.
High Reliability & Long Service Life: With proper maintenance, lifespans of 25-30+ years are standard.
Excellent Cost-to-Capacity Ratio: Often more economical than dry-types for medium to large power ratings.
Ratings: Precisely determine required kVA/MVA capacity, voltage ratios, and vector group.
Losses & Efficiency: Prioritize units with low no-load loss (core loss) and load loss (copper loss) to minimize lifetime operating costs. Compliance with international efficiency standards (like IEC 60076) is key.
Impedance: Choose percentage impedance (%Z) based on system short-circuit requirements.
Installation Environment: For outdoor use, specify appropriate Ingress Protection (IP) codes. Zisheng manufacturing standards accommodate harsh environments.
Ensure a level, solid foundation capable of supporting the total weight.
Establish a reliable, low-resistance grounding system.
Follow strict oil filling, degassing, and commissioning procedures.
Regular Oil Monitoring: Schedule periodic Dissolved Gas Analysis (DGA) to detect internal faults like arcing or overheating early. Check dielectric strength and moisture content.
Visual and Physical Checks: Monitor oil level in the conservator, check for leaks, record top-oil temperature, and ensure silica gel in breathers is active (blue color).
Termination and Cleaning: Keep bushings clean and check tightness of external connections.
Fire Safety: As oil is flammable, install units per local codes, with adequate separation or fire barriers if needed.
Pressure Relief: Never disable pressure relief devices. They are critical for safety.
Lockout/Tagout: Always de-energize, ground, and follow safe work practices before any close inspection or servicing.
Winding Insulation Failure: Caused by aging, moisture, or overloading. Detected via increasing Furan Analysis or Dielectric Loss measurements.
Core Grounding Issues: Can cause localized heating and increased core loss.
Bushing Failures: Degradation can lead to flashover or explosions.
Oil Degradation: Oxidation or contamination reduces insulating and cooling properties.
Tap Changer Problems: Contact wear or mechanism failure in On-Load Tap Changers (OLTC).
Buchholz Relay alarm → Check gas composition.
Sudden pressure rise → Immediate shutdown and investigation.
High temperature alarms → Check loading and cooling systems.
| Feature | Oil-Immersed Transformer | Dry-Type Transformer |
|---|---|---|
| Cooling/Insulating Medium | Dielectric Oil | Air, Epoxy Resin, Vacuum Cast |
| Fire Safety | Oil is flammable; may require containment | Generally flame-retardant; suitable for indoor buildings |
| Environmental Impact | Requires oil containment; end-of-life oil disposal | Generally lower direct environmental risk |
| Cooling Efficiency | Excellent; higher overload capability | Good; limited by air circulation |
| Maintenance Needs | Regular oil testing and processing | Mostly limited to cleaning; less intensive |
| Typical Cost | Lower for medium/large power ratings | Often higher for equivalent ratings |
| Ideal Application | Outdoor substations, utility, heavy industry, high capacity | Indoor installations, buildings, hospitals, lower capacity |
Higher Efficiency: Use of amorphous metal cores to drastically reduce no-load losses.
Digitalization & IoT: Integration of online monitoring systems for DGA, temperature, and partial discharge, enabling predictive maintenance.
Eco-Friendly Fluids: Development and use of biodegradable ester-based oils with higher fire points.
Compact Design: Achieving higher power density without compromising reliability.
