Qingdao Brewery applied a variable frequency drive (VFD) to the brewing room's beer supply system. By controlling the speed of the beer pumps through the VFD, beer loss was reduced, energy was saved, mechanical failures of the pumps and valves were decreased, and the quality of beer filling was improved, resulting in significant economic benefits. I. Purpose of the Modification The original brewing room's beer supply system is shown in Figure 1. The system had the following three main drawbacks: [align=center] Figure 1 Schematic diagram of the original beer supply system [/align] 1. The use of a throttling valve to regulate pump flow resulted in resistance losses and wasted energy. 2. Regardless of the process control quantity, the beer pump always operated at the industrial frequency of 50Hz, with a speed of 2900 r/min, resulting in significant mechanical losses. 3. The impact during pump startup easily caused a large amount of foaming in the beer, increasing beer loss. In addition, inconsistent pressure also affected the quality of beer filling. II. Application of the VFD Analysis showed that the advantages of using VFD in the beer supply system to obtain the required pressure and flow rate are: 1. 1. Flow control is achieved without sacrificing pump head. 2. The pump operates at <50Hz, reducing power consumption and mechanical wear on moving parts. 3. Variable frequency soft start and soft shutdown avoid the pressure instability issues of previous wine supply systems, while also ensuring the normal operation of the pump and other mechanical equipment. The variable frequency speed control wine supply system is shown in Figure 2. New components include an ACS501-016-3/315kW frequency converter, a YYB-1MPa pressure transmitter, air switches, relays, and reactors. [b][align=center]For details, please click: Application of Frequency Converters in Wine Supply Systems[/align][/b]