Abstract: Utilizing frequency converter technology to retrofit power plant fans is one of the important ways to save energy, reduce consumption, and improve system performance. This paper describes and analyzes the application examples and characteristics of high-voltage frequency converters in power plant fans. Keywords : Fan; Thermal power plant; High-voltage frequency converter; Optimized operation 1 Introduction Fans are a type of power machinery that is widely used and consumes a large amount of electricity. In China, the annual electricity consumption of fans accounts for more than 10% of the total consumption. In the power, steel, coal, and metallurgical industries, the electricity consumption of fans often accounts for more than 20% of the production electricity consumption. Therefore, research on energy saving of fans has significant economic importance. In fan systems, flow regulation is often achieved by changing the damper opening, which generates additional pressure loss on the dampers, wasting a large amount of energy. For example, in a thermal power plant, the forced draft fan provides air for boiler combustion, and the induced draft fan removes the high-temperature flue gas generated by boiler combustion. Due to frequent changes in unit load, and to ensure the stability of boiler furnace negative pressure, flue gas oxygen content, and corresponding steam temperature and pressure, the forced draft and induced draft fan volumes, as well as the pulverized coal quantity, need to be adjusted promptly. Airflow regulation is generally achieved by adjusting the inlet guide vanes, with the vane opening frequently varying between 60% and 80%. The throttling loss of these vanes is 20% to 30% of the fan's rated capacity. Upgrading the fan system using variable frequency speed control technology not only saves energy but also makes the system operation more rational and reliable, which has become a consensus among engineering technicians. However, there is very little literature reporting on how to determine the fan's speed ratio to operate in the high-efficiency zone and achieve optimized fan efficiency. For a single fan, the problem is relatively simple; however, when multiple fans are connected in parallel or series, it is essentially a nonlinear programming problem. This paper analyzes the operating conditions of the wind turbine system, classifying it into two types based on pipeline characteristics. Optimal control strategies are analyzed for single-fan operation and multiple-fan parallel operation, determining the optimal speed regulation ratio. The system has been put into operation in our power plant, achieving good economic and social benefits. [b][align=center]For more details, please click: Research on the Application of Frequency Converters in Power Plant Wind Turbines[/align][/b]