Energy saving principle of water ring vacuum pump
As can be seen from the formula S=Q/P1 of the vacuum pump pumping rate, when the vacuum system leakage rate Q is constant, the effective pumping rate S of the mechanical pump is inversely proportional to the vacuum degree P1 of the pre-water ring vacuum pump that needs to be achieved. The smaller P1 is, the higher the effective pumping rate of mechanical pump is required; If the value of P1 is greater than the actual value, there will be excess vacuum, which will result in the waste of the effective pumping rate of the mechanical pump. From S=Q/P1, it can be concluded that P1=Q/S. From this equation, it can be seen that the vacuum degree P1 required for production can be used as the regulating quantity. In this way, a P0 value can be set according to the production condition, and the frequency of the frequency converter can be adjusted by PID control, so as to adjust the effective pumping rate of the mechanical pump to achieve the purpose of energy saving and consumption reduction. Change the principle of the water ring in the process of industrial field use, water ring vacuum pumps usually adopt a fixed valve to control the water supply when the motor speed must be direct water supply way and water level within a certain range, the water ring which is formed by the high water level, water ring is small, which is formed by the water level is low or when the water ring is larger, can make the power consumption increased, the water ring vacuum pump efficiency drop, increase power consumption.
Again at the same time due to changes over the working state of water supply pipe water supply, this makes the water ring vacuum pump vacuum under the influence of certain, and increase the energy dissipation of this study is to make the water ring vacuum pump motor speed at the speed of the normal vacuum condition, people with the best speed control for water injection water ring vacuum pumps, make its have been working in the most efficient condition, overcome the defect of the existing technology. The hardware system platform of water link control device of water ring vacuum pump mainly includes general upper computer, PLC, water pump inverter, vacuum pump inverter, water pump motor, vacuum pump motor, water pump, water ring vacuum pump, true empty box, vacuum sensor and vacuum pressure gauge. The control system structure is shown in figure 2. The figure 2 shows that vacuum sensor, vacuum degree of vacuum in the actual data transmission to the PLC, with preset vacuum standard PID adjustment, form a closed-loop control system to determine whether a vacuum pump frequency converter, then control the rotating speed of vacuum pump motor, water ring vacuum pump to adjust the vacuum degree of vacuum box, at the same time, the vacuum pump inverter power value feedback back into PLC. The control of water flow can be set by the upper computer.
