By precisely controlling the operating speed and load of equipment in the coal conveying system of thermal power plants， energy consumption can be significantly reduced. For this purpose， in-depth research has been conducted on energysaving optimization and automatic control of coal conveying systems in thermal power plants based on variable frequency speed regulation technology. Analyze the structure of the coal transportation system in thermal power plants， determine that it is mainly divided into two parts: upper computer and lower computer. Design the logical configuration of the upper computer， and implement optimization based on frequency conversion speed regulation technology for the lower computer to achieve automatic control of the coal transportation system in thermal power plants. In order to verify the experimental effectiveness of this method，tests were conducted. The test results show that the energy-saving optimization automatic control method for coal conveying systems in thermal power plants based on variable frequency speed regulation technology can effectively reduce energy consumption during low load or idle times， ensure that coal conveying equipment operates in the optimal working state， and improve the economic benefits of thermal power plants.