Research On Key Technologies For Diaphragm Pumps’ Control

In recent years, with the pipeline deliver equipment developing larger, limited by the cost and technique, one diaphragm pump can’t complete the conveying task. So, in many equipments, several diaphragm pumps convey the slurry to the same pipeline at the same time. For the inherent geometrical periodic variation, the instantaneous alternating flow and pressure of the reciprocating diaphragm pump with single acting cylinder is pulsating. When two or more diaphragm pumps transport coal slurry to the same system, the amplitude of the flow volatility and pressure fluctuations is increased. This may not only damage the pipeline and the diaphragm pump seriously but also lead to serious accident. Therefore, when shafts of two or more pumps are rigidly connected, the fluctuation phase must be staggered with each other to minimize fluctuation. In this paper, the electrical synchronous control is used to decrease the amplitude and in the premise of the diaphragm pumps had the same speed, distract their phase angle to inhibit the pulse of the diaphragm pump group.Firstly, the diaphragm pump on the structure, principle, actuality and the developing tendency are introduced. Secondly, the flow pulsation and the pressure fluctuation of the diaphragm pump are analyzed, and the optimal angle of flow peak disperse is got. Thirdly, the synchronized control of multiply diaphragm pumps’ motors based on fuzzy PID compensator was proposed and the fuzzy PID compensator is designed.The simulation experiment of the synchronized control of multiply diaphragm pumps’ motors based on fuzzy PID compensator is carried out. The PLC control system of the diaphragm pumps synchronous driving is designed and the actual control system is tested. Both the simulation and the experiment proved that control system can converge with high speed in cases of with disturbance and without disturbance. And the system can run stable with good trends performance and synchronous performance. It is proved that the algorithm of the synchronous control is effective for diaphragm pumps.Finally, the other problems are analyzed in the diaphragm pumps synchronous control system and the interested directions in the future research.