Principle of energy-saving technology for variable frequency speed regulation of

According to the characteristics of screw pumps, the adjustment of their operating conditions is mainly to regulate the flow rate. As a volumetric pump, screw pumps cannot regulate the flow rate by adjusting the opening of the outlet valve. Therefore, the commonly used methods for regulating the flow rate of screw pumps are to control the reflux rate by adjusting the opening of the pump bypass valve, and to adjust the speed of the screw pump. Although the former is simple and convenient to adjust, it causes huge energy waste. Therefore, by converting the frequency of the screw pump motor and changing the motor speed, the working condition adjustment of the screw pump can be achieved, which is a feasible technical approach to meet the process operating conditions. According to the working principle of volumetric pumps and the characteristics of screw pumps, it can be seen that the displacement of screw pumps is linearly related to the rotational speed, while the viscosity properties of the oil remain unchanged. Therefore, by reducing the rotational speed of the screw pump, the output can be reduced, thereby reducing the load on the motor and minimizing energy waste.