High-voltage complete switchgear: Key supporting equipment in energy structure adjustment

Driven by the global "dual carbon" goals, China's energy structure is accelerating its transition toward cleaner and low-carbon development. By the end of 2023, renewable energy accounted for 48.8% of installed capacity, making the construction of new power systems a core task. As the core equipment for power distribution, control, and protection in power systems, high-voltage complete switchgear (hereinafter referred to as "switchgear") plays an indispensable role in this transformation. Its technological upgrades and application innovations directly support key links such as renewable energy grid integration, grid intelligence, and energy storage system integration.

1.Support large-scale grid integration of renewable energy and open up clean power transmission channels

Renewable energy (wind power, photovoltaics) is characterized by intermittency and volatility, and its grid connection process requires solving issues such as voltage matching, power fluctuation control, and fault prevention. As a "bridge" between wind farms, photovoltaic power stations, and the grid, switchgear cabinets fulfill the core functions of energy collection, voltage boosting, and grid connection.

Taking wind power as an example, the electricity generated by the wind turbine units is stepped up by the box transformer, then collected through switchgear to the wind farm's step-up station, and then connected to higher-level grids. During this process, the switchgear must have reliable overcurrent, overvoltage, and short-circuit protection capabilities to handle power fluctuations caused by sudden changes in wind speed and prevent faults from spreading to the main grid. For distributed photovoltaics, the switchgear on the distribution network side needs to meet the needs of small-capacity, multi-node access. Its intelligent protection function can adjust voltage and current in real time to ensure smooth output from the photovoltaic system is injected into the distribution network. Data shows that in 2023, over 90% of newly added wind and photovoltaic installations in China adopted highly reliable high-voltage switchgear, ensuring efficient transmission of clean electricity.

2.Empowering the intelligent transformation of the power grid, improving system flexibility and dispatching efficiency

New power systems require the grid to have "source-grid-load-storage" coordination capabilities, and intelligent switchgear is the terminal core to achieve this goal. Modern smart switchgear integrates sensors, communication modules, and edge computing units, capable of real-time data collection of current, voltage, temperature, and partial discharge, and uploading it to the grid dispatch center via IoT technology.

For example, in intelligent distribution networks, status monitoring data from switchgear cabinets can help dispatch centers accurately grasp line load conditions, dynamically adjust distributed energy output, and balance supply-demand gaps. At the same time, the remote control function allows maintenance personnel to operate switchgear switchgear from the backend, reducing on-site operation time and improving emergency response speed. Additionally, the application of predictive maintenance technology can analyze the operating data of switchgear to detect potential faults in advance, reducing the risk of outages—this is especially important for grids that rely on renewable energy, as any unexpected outage could lead to interruptions in power supply.

3.Ensure the safety and stability of new power systems and adapt to complex grid topologies

With the widespread integration of distributed energy and energy storage systems, the grid topology is becoming increasingly complex, short-circuit current characteristics are changing, and higher safety requirements are being placed on switchgear cabinets. The switchgear's rapid breaking capability (usually completing fault break within 20ms) is key to preventing fault escalation; its insulation performance and mechanical lifespan directly affect the continuous operation of the power grid.

To meet the demands of new power systems, switchgear technology is evolving towards environmental friendliness and high reliability. Traditional SF6 gas switchgear is gradually being replaced due to its greenhouse effect, and environmentally friendly insulating media such as dry air and nitrogen gas mixtures are now widely used. These switchgear not only meet the dual carbon goals but also have excellent insulation performance, adapting to the operational demands of extreme environments such as high temperature and high altitude. For example, in photovoltaic power stations on the Qinghai-Tibet Plateau in China, environmentally friendly switchgear ensures stable operation thanks to its low-temperature resistance and resistance to altitude reactions.

4.Supporting efficient integration of energy storage systems to achieve "source-storage" collaboration

Energy storage is the core means to solve the intermittent problem of renewable energy, and switchgear cabinets are the key nodes connecting energy storage systems to the grid. In energy storage power stations, switchgear is used to control the charging and discharging processes of energy storage units, enabling the storage and release of electrical energy. Due to frequent charging and discharging of energy storage systems, switchgear must have high mechanical lifespan (typically over 10,000 operations) and rapid response capability to accommodate dynamic power adjustment.

Additionally, the protective features of switchgear can prevent power accidents caused by energy storage unit failures (such as battery thermal runaway). For example, in electrochemical energy storage stations, switchgear can monitor battery pack voltage and temperature in real time, quickly cutting off circuits when abnormalities occur to ensure station safety. With the rapid growth of energy storage installed capacity (China's installed capacity exceeded 30GW in 2023), the demand for switchgear will further expand, and technological innovation will also drive efficient integration of energy storage systems.

Conclusion

As the "nerve endings" of the power system, high-voltage complete switchgear plays an irreplaceable role in adjusting the energy structure. From supporting renewable energy grid integration to empowering grid intelligence, from ensuring system security to supporting energy storage integration, technological upgrades and application innovations in switchgear are driving the construction of new power systems. In the future, as the energy transition deepens, switchgear will develop toward smarter, more environmentally friendly, and more reliable directions, providing solid equipment support for achieving the "dual carbon" goals.