Design of Variable Flow and Variable Pressure Efficient Control Function of Ship Central Cooling Water

Aiming at the problem of high energy consumption in domestic marine central cooling water system, the characteristics of seawater pump have been analyzed in detail. A variable-flow pressure control method has been developed to control the speed of seawater pump. The control function method is given for optimal design of ship control system. The total seawater flow can be evaluated according to the load of main engine and the inlet temperature of seawater. The speed ratio is calculated by the control function. The range of speed ratio is determined by the efficiency of frequency converter and pump. The results show that the improved controlling function reduces the energy consumption of the system significantly.