800 KVA transformer, 15 kV x 400 V three-phase

1. Product Description

The 800 KVA three-phase transformer with an input voltage of 15 kV and an output voltage of 400 V is an essential piece of equipment for converting electrical energy from medium voltage to low voltage. This transformer, which we will analyze as a practical example, is designed for industrial and commercial applications requiring the conversion of high-voltage energy into usable power for low-voltage equipment.

2. Materials and Components

• Nucleus:

  • Material: Rolled silicon steel, chosen for its excellent magnetic properties which reduce hysteresis and eddy current losses.
  • Construction: The core is made of thin steel plates stacked together, bonded to minimize energy losses and optimize magnetic field distribution.

• Windings:

  • Material: Copper or aluminum, with copper generally preferred for its higher conductivity.
  • Construction: The windings are wrapped around the core and designed to handle the flow of current and voltage efficiently and safely.

• Insulation:

  • Material: Mineral oil or resin, depending on the transformer type. Mineral oil is used for cooling and insulation, while resin is a more modern choice that offers greater environmental protection.

• Cabin:

  • Construction: Rugged metal, designed to protect internal components and ensure operational safety.

3. Dimensions and Weight

• Rated Power: 800 KVA
• Input Voltage (Medium Voltage): 15 kV
• Output Voltage (Low Voltage): 400 V
• Dimensions: Varies depending on the specific design, but in general, a transformer of this size can have a considerable footprint, often in the range of 1.5 x 2 x 2 meters.
• Weight: Generally between 2,000 and 3,000 kg, depending on materials and construction.

4. Mechanical Characteristics

• Efficiency: High, with low energy losses thanks to the use of silicon steel and high-quality windings.
• Thermal Stability: The transformer is designed to operate at high temperatures, with cooling systems (such as oil or resin) that prevent overheating.
• Insulation: Excellent, thanks to the use of high-quality insulation materials that protect against electrical discharges and external contamination.

5. Usage Procedure

1. Installation:
   • Place the transformer on a stable, level base.
   • Make sure the cabin is adequately ventilated and the transformer is accessible for maintenance.
2. Connection:
   • Connect the high voltage cables to the medium voltage connections and the low voltage cables to the output connections.
   • Check that the connections are secure and that there are no signs of wear or damage.
3. Ignition:
   • Turn on the transformer and monitor operating parameters such as voltage, current, and temperature.
   • Check for any signs of malfunction or abnormality.

6. Matching accessories

• Monitoring Devices: Temperature and humidity sensors, load indicators, and warning systems.
• Cooling Systems: Additional fans or water cooling systems if used in hot environments.
• Protective Devices: Circuit breakers and fuses to protect the transformer from overloads and short circuits.

7. Mathematical formulas

• Apparent Power: S=P2+Q2S = \sqrt{P^2 + Q^2} $$S$$ $$=$$ P 2 + Q 2 ​Where PP $P$ is the active power and QQ $Q$ is the reactive power.
• Efficiency: Efficiency = Output Power Input Power × 100% \text{Efficiency} = \frac{\text{Output Power}}{\text{Input Power}} \times 100 \% $$\text{Efficiency}$$ $$=$$ Input Power Output Power ​× $$100\%$$
• Core Losses: Calculated by eddy current analysis and hysteresis losses.

8. Materials He Can Work with

• Resistive Loads: For example, electrical equipment that requires continuous power.
• Inductive Loads: Electric motors and other devices that involve a variable flow of current.
• Capacitive Loads: Can also be used with capacitive loads, but it is important to check the specifications to avoid stability problems.

9. Maintenance

• Regular Inspection: Check oil level, condition of core and windings, and monitor for signs of wear.
• Cleaning: Keep the cabin and its components clean and free of dust and debris.
• Safety Checks: Ensure all protective devices and warning systems are functioning.

10. Used Goods Check

• General Condition: Visually inspect the transformer for signs of damage, corrosion, or wear. Check the condition of the insulation and for leaks.
• Functional Tests: Perform functional tests to ensure that all parameters are within specified limits.
• Documentation: Check maintenance documentation, last inspection date, and certificates of conformity.

11. Sectors of Use

• Industry: Used to power industrial machinery and equipment.
• Commercial: For applications in commercial buildings requiring reliable energy transformation.
• Public Sector: Used to provide energy to public infrastructure and services.

12. Advantages of Buying Used

• Lower Cost: Buying a used transformer can result in significant savings over buying a new one.
• Reliability: Well-maintained transformers can perform as well as new, especially if they have been used sparingly.
• Immediate Availability: Used transformers are often available immediately, reducing waiting times.

In summary, the 800 KVA three-phase transformer, with an input voltage of 15 kV and an output of 400 V, represents a robust and versatile solution for electrical energy transformation. With proper maintenance and testing, a used transformer of this type can offer excellent value and reliable performance for many industrial and commercial applications. If you have any other questions or require further details, I'm here to help