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The electric pitch control systems for fans use two types of energy storage systems: one uses supercapacitors, and the other uses batteries. Batteries are an effective energy storage device for many applications, and battery storage was also widely used in pitch control systems at first. However, with the emergence of supercapacitors and their beginning use in wind turbine pitch control, their unique advantages became fully evident. The pitch system can continuously adjust the blade spacing to meet the operating principles of the wind turbine. This not only ensures that the fan maintains a constant power output, preventing blade breakage due to excessive mechanical stress, but also reduces the mechanical stress on the turbine structure, thereby extending its service life. As is well known, during the operation of a fan, if there is a fault in the power grid, the fan must activate its emergency backup system. A backup system is an energy storage system that provides sufficient electrical power to bring the fan blades back to their neutral position, enabling a safe shutdown and preventing the fan from suffering severe damage or even being completely destroyed due to excessive or uneven wind forces. It is reported that the wind turbine pitch control system uses supercapacitors as the energy storage mechanism, and these supercapacitors have five advantages over batteries: first, they offer high power density, which enables the release of large amounts of power instantly. Unlike batteries, supercapacitors can release high power instantly, thereby ensuring that the blades return to the neutral position quickly in the event of a grid failure. Given that supercapacitors charge much faster than batteries, they can also provide high reliability in situations where there is a short-term mismatch between power demand and supply capacity. Second is to reduce the total purchase cost. The initial investment cost for an electric pitch control system using supercapacitors is the same as that of a battery-based system, but electric pitch control systems that use batteries (without energy storage devices) require more complex charging and monitoring systems, which results in higher costs. Systems that use supercapacitors require fewer components, and mechanisms such as mechanical installation and vibration damping are also simpler compared to battery systems. Third, it has a long service life, and its aging cycle is predictable. Under normal operating conditions, supercapacitors have an average lifespan of 12 years, which is mainly attributed to two factors: first, they can operate within a wide temperature range of -40°C to 65°C; second, they can function reliably for 500,000 to 1,000,000 charge-discharge cycles. Unlike supercapacitors, batteries have a narrow operating temperature range; harsh environmental conditions and continuous charging and discharging can severely damage them, requiring replacement every two to four years. Fourth, there are no costs associated with heating or cooling. Batteries are susceptible to extreme temperatures, while supercapacitors are not affected by them. The battery requires a heating and cooling system. Therefore, the design cost of using a battery system is inevitably higher, while supercapacitors do not require such additional high maintenance costs. Fifth is its light weight. Battery energy storage systems often have to be designed on a very large scale to meet peak power demands, and systems that use batteries are relatively larger and more bulky. Supercapacitors are significantly lighter, as they are capable of releasing high power instantly, which is sufficient to meet peak power demands; therefore, there is no need for a oversized design. In the long term, batteries incur high maintenance and replacement costs, whereas supercapacitors can avoid such expenses. The wind turbine pitch control system uses supercapacitors as energy storage devices, which can save a great deal of manpower, resources, and money, offering better cost-performance.