通常双缸单作用活塞泵的恒转速运行会导致管路流量波动,使之在恒流量场合较少应用.对双缸单作用活塞泵的运动建立微分方程,给出了MATLAB7的仿真结果,提出了活塞近似匀速运动的条件,并对电动机转轴的角速度的计算方法作了讨论,得出了在中、低速运行时采用变角速度控制能近似实现恒流量的结论. Usually, the constant speed operation of double cylinder single-action piston pump will lead to the fluctuation of pipeline flow, which makes it less suitable for constant flow.Differential equation is established for the motion of double-cylinder single-acting piston pump, and the simulation result of MATLAB7 is given. The approximate piston moving condition is discussed, and the calculation method of the angular velocity of the motor shaft is discussed. The conclusion that the constant flow rate can be approximated by the variable speed control can be obtained at medium and low speed.