Abstract: This article introduces the product performance and technical characteristics of Siemens' new generation frequency converter G150, as well as the frequency conversion renovation of the Xindesheng Pumping Station of Hangzhou Water Supply Corporation, the technical renovation plan, and the equipment used. Keywords : Frequency converter, pumping station [b]1 Introduction[/b] The frequency conversion project of Xindesheng Pumping Station in Hangzhou City is a new frequency conversion speed control system added by Hangzhou Water Supply Corporation to meet the growing supply and demand in Jiubao and Xiasha areas, while retaining the original pump equipment. For this project, the following products were mainly used: Siemens SINAMIC SG150 frequency converter, Siemens frequency conversion motor, industrial control computer, Siemens S7-300 series PLC, etc., forming a monitoring system. The frequency converter control system of this project adopts the most advanced SIEMENS SG15O series products with digital vector control function. Based on the characteristics of the small power grid capacity in the water treatment industry, in order to ensure that the frequency converter does not interfere with the normal operation of other system equipment and that the harmonic content meets the GB/T14549/93 and IEEE519/1992 standards, a six-pulse rectifier converter is adopted. [b]The frequency converter control system can realize the following functions:[/b] (1) Stepless speed regulation function: It can completely realize stepless adjustment of the pump speed and realize precise control of pressure, flow and other parameters in the states of start-up, operation and peak shaving. (1) No throttling loss during the throttling process; (2) Speed ​​limiting function: The maximum and minimum speed of the motor can be set through the system logic to ensure that the motor will not stop or exceed the rated speed when the control system and speed setting circuit fail; (3) Soft start function: This device can ensure that the water pump driven by the asynchronous motor can start smoothly and operate economically, avoid the impact of the starting current on the power grid and motor, thereby reducing the impact on the power supply system, and can save maintenance costs for the motor and high-voltage switch, and improve the service life of the motor and high-voltage switch. [b][align=center]For details, please click: Application of frequency converter in water plant[/align][/b]