The diverse applications of insulating oil in power systems

2025-07-16

In the vast and complex power system, Insulating Oil is like a shining "multifunctional star", playing an indispensable role in various key links. From large transformers in power plants, to distribution equipment on urban streets, to electrical installations in factory workshops, insulating oil is ubiquitous, providing a solid guarantee for the stable production, transmission, and distribution of electricity.

Transformers, as the core equipment for voltage conversion and energy transmission in power systems, rely heavily on insulating oil. Insulating oil plays two key roles in transformers: insulation and heat dissipation.

In terms of insulation, there are high-voltage windings and iron cores inside the transformer. Insulation oil serves as an electrical insulation medium to isolate components with different potentials, prevent current leakage, and avoid short circuit accidents. Its excellent insulation performance ensures that the transformer can operate safely and stably in high voltage environments. For example, in ultra-high voltage transmission systems, transformers need to withstand voltages of millions of volts, and the high-quality insulation properties of insulating oil enable current to flow orderly in the windings without accidental leakage, thereby ensuring efficient power transmission.

The heat dissipation function is equally crucial. During the operation of transformers, a large amount of heat is generated due to winding resistance and iron core losses. The insulating oil transfers the heat from the internal components of the transformer to the external radiator through its own circulation flow, and then dissipates it to the surrounding environment. This process is like the blood circulation system of the human body, continuously taking away heat to prevent the transformer from being damaged due to overheating. High quality insulation oil has good thermal conductivity, which can quickly and effectively dissipate heat, ensuring that transformers are always within the appropriate working temperature range and extending the service life of equipment.

Capacitors are mainly used in power systems for reactive power compensation, improving power factor, and stabilizing voltage. Insulating oil plays a role in insulation impregnation and moisture insulation in capacitors. Inside the capacitor, insulating oil is filled between the electrodes, enhancing the insulation performance between the electrodes, preventing electric field breakdown, and improving the working voltage and stability of the capacitor. At the same time, insulating oil can isolate external moisture and humidity, avoiding the insulation material inside the capacitor from being affected by moisture and reducing its performance. For example, in power capacitor banks, the good insulation and moisture resistance of insulating oil ensure that the capacitors can operate efficiently and reliably, providing stable support for reactive power compensation in the power system and optimizing power quality.

Switchgear is a key device for controlling the on-off of power systems, and insulating oil plays a dual role in insulation and arc extinguishing. Under normal working conditions, insulating oil provides reliable insulation between the conductive parts of the switch and the casing, as well as between different poles, ensuring that current flows along the predetermined path and preventing leakage accidents. When the switch is opened or closed, an arc will be generated between the contacts, and the temperature of the arc is extremely high. If it is not extinguished in time, it will cause serious damage to the switchgear and even lead to safety accidents such as fires. Insulating oil, with its high thermal conductivity and rapid cooling characteristics, can quickly absorb the heat of the arc, extinguish the arc quickly, and protect the safe operation of switchgear. For example, in high-voltage oil immersed circuit breakers, insulating oil plays a core role in the arc extinguishing process, ensuring that the circuit breaker can quickly and reliably cut off the fault current and ensure the safety and stability of the power system.

In cable systems, insulating oil is used for insulation, impregnation, and cooling. As the "blood vessel" of power transmission, cables need to operate stably in different environments for a long time. Insulating oil is filled between the insulation layer and sheath of the cable, enhancing the insulation performance of the cable and preventing current leakage. At the same time, the impregnation effect of insulating oil makes the insulation material of the cable more tightly bonded, improving the overall insulation strength. During the operation of the cable, heat is generated due to the current passing through, and the cooling effect of the insulating oil can effectively dissipate the heat, ensuring the normal operating temperature of the cable. For example, in underground cable laying, the multiple functions of insulating oil ensure that the cable can stably transmit power in complex underground environments, avoiding faults caused by decreased insulation performance or overheating.

The application of insulating oil in the power system is extensive and critical, and its performance directly affects the operational reliability of power equipment and the overall stability of the power system. With the continuous development of power technology, the requirements for the performance of insulating oil are also constantly increasing. In the future, the research and development of high-performance and environmentally friendly insulating oils will become an important direction for industry development to meet the growing demand for electricity and promote the power system towards a more efficient, safe, and green direction.