中文摘要：

基于液压传动存在的成本高、效率低等不足，提出一种新型的把电机转子作为柱塞泵缸体的液压电机泵调速系统，并建立了系统的数学模型。通过改变电机转速的方式调节泵的输出流量，使电机提供的功率与负载所需功率相匹配，从根本上提高液压调速系统的效率。针对传统直接转矩控制存在电流、磁链和转矩脉动大以及低速时难以精确控制等缺点，将滑模变结构理论运用到直接转矩控制中，以提高系统的鲁棒性和快速性。对转速和转矩阶跃变化进行仿真研究，仿真结果表明该策略具有良好的鲁棒性和快速性。

英文摘要：

Considering the shortages in hydraulic drive system, a novel hydraulic motor pump speed regulating system that the rotor was used as piston pump body was proposed. Based on analyzing the generation mechanism, its model was built. To adjust the output flow of pump by regulating speed of motor, to make the motor output power match the load, the efficiency of hydraulic speed regulating system was improved. Aimed at those disadvantages associated with conventional direct torque control, such as high current, flux and torque pulsation and difficulty to accurately control at very low speed, a new variable structure sliding mode control strategy was proposed to enhance the robust and fast. Under the condition of drastically changed speed and torque, the simulation was performed. Results show that the suggested method is robust and fast.