Powerplant Transformers

At the source of electricity production -- power plants, transformers play a crucial role. It is the first critical device for efficient transmission and distribution of electrical energy after it is generated from the generator. Choosing a power plant transformer with excellent performance and reliable operation is the cornerstone of ensuring stable and economical operation of the entire power system. With many years of deep cultivation in the field of power equipment, Kechang Electric will analyze the core points of power plant transformers for you.

Power plants, depending on their type, output voltage class, and installation environment, primarily select the following transformers:

Boosted main transformer (core equipment)

1. Type: The vast majority use oil-immersed transformers.

2. Reason: The voltage emitted by the power plant (usually 6.3 kV, 10.5 kV, 13.8 kV or 20 kV) needs to be raised substantially to 110 kV, 220 kV or even 500 kV and above in order to carry out long-distance transmission and reduce line losses. Oil-immersed transformers have irreplaceable advantages in the high voltage and large capacity sectors, including excellent heat dissipation performance, high insulation strength, strong overload capacity, mature technology and high cost performance.

3. Kechang Solution: Our company provides a series of high-efficiency oil-immersed transformers such as S13, S20, and S22, with voltages covering 10kV to 35kV, and can be expanded to higher voltage levels. The no-load loss is reduced by more than 30% compared with traditional products, meeting the needs of power plants. The ultimate requirements for efficiency and reliability.

Transformers for plant use

1. Type: Usually dry type transformer.

2. Reason: Used to power the power plant's own auxiliary equipment (such as water pump, fan, control system, etc.), reduce the high voltage power to 380 V/220 V. Because it is installed in the factory building or power distribution room, it has extremely high requirements for fire and explosion protection. The flame-retardant, pollution-free and maintenance-free features of dry-type transformers perfectly fit this scenario.

3. Ke Chang Solution: Our company's SCB12, SCB14, SCB18 and other series dry-type transformers are cast with epoxy resin, with high insulation level and noise as low as 52dB (A). They are very suitable for safety-sensitive areas such as power plant distribution rooms.

Other special transformers

1. Start Transformer: Provide starting power for the plant system during the initial stage of power plant construction or after the entire plant is shut down.

2. Contact Transformer: Busbar for connecting different voltage classes.

1. Reliability is preferred: The continuous operation of the power plant requires strong requirements on whether the transformer can withstand long-term full load as well as short-term overload and short-circuit resistance. Kechang transformer passed GB/T1094.5 short circuit test verification, design life ≥ 30 years.

2. Efficiency is essential: The transformer's own losses are a long-term running cost. Products with high energy efficiency classes (such as S22, S20 energy efficiency class 1) should be selected. The no-load loss of Kechang S22 series transformers is greatly reduced, which can save power plants huge electricity bills throughout their life cycle.

3. Voltage regulation: Voltage generation fluctuations require a voltage regulating tap changer (non-excitation or on-load voltage regulation) to ensure continuous output voltage stability.

4. Impedance voltage matching: Impedance voltage needs to match with the grid system to limit short-circuit current and protect equipment safety.

5. Perfect protection: It must be equipped with gas relay (gas protection), pressure release valve, temperature controller and other protection devices to ensure quick action in case of failure. Kechang products come standard with a complete set of safety protection devices.

6. Supplier qualification and after-sales service: Choosing a supplier like Kechang Electric with international certifications such as ISO9001, strong R & D capability and perfect after-sales service network is the guarantee for the long-term stable operation of the project.

Transformer losses consist of no-load losses (iron losses) and load losses (copper losses).

• No-load losses: Losses occur when the transformer is energized, because of the hysteresis and eddy current effects of the iron core.
• Load loss: The transformer is powered on to run the boost or buck, which will change according to the square of the generated load current, and the reason is caused by the winding resistance.
• Selection strategy: For a power plant's boost main transformer, its load factor is usually high, approaching continuous full load operation. Therefore, reducing load losses is more significant for saving operating costs. Products with low load losses should be preferred. However, power plants also have periods of peak shaving or low-load operation, when the specific gravity of no-load losses rises. Therefore, the most ideal choice is a high efficiency transformer (such as Kechang S22 series) in which both no-load loss and load loss are at a low level. A full life-cycle cost analysis is required, not just a comparison of initial purchase prices.

Application scenarios:

• Thermal/Nuclear Power Plants: As the main transformer, the generator outlet voltage is raised to the transmission voltage.
• Hydroelectric power plants: Often remote, with higher requirements for moisture resistance and environmental adaptability of transformers.
• Wind Farm/Photovoltaic Power Station: Pools and boosts the electrical energy generated by the dispersed wind turbine or photovoltaic array and sends it to the grid. box-type substation solutions are widely used in this field and can be deployed quickly and flexibly.
• Pumped storage power station: It has both power generation and electric working conditions, and has special requirements for transformers.

Conclusion The choice of power plant transformer is a complex systematic project, which is related to the safety and efficiency of the entire energy project. As a professional manufacturer of durable electrical equipment, Kechang Electric not only provides a full range of high-efficiency and reliable transformer products from 10kV to 35kV, but also provides optimal technical selection suggestions and full life cycle value analysis for your specific projects.