伺服泵的电动变量机构

针对一体化电动静液作动器(Electro-hydrostatic actuator,EHA)中电动机转速与泵排量双变量控制的需要,设计了一种电动变量伺服泵,利用电动变量机构来改变泵的排量,取代传统伺服变量泵中的液压伺服机构。对变量泵变量机构驱动力矩进行了分析计算,选用直流伺服电动机作为变量机构执行单元,通过减速机构和扇形齿轮直接驱动斜盘的摆动轴,改变斜盘倾角从而实现变排量,并设计了基于DSP的数字伺服控制器。建立其数学模型, 进行了仿真分析,仿真结果表明伺服泵输出排量可实现无超调的快速调节,调节时间和小信号下的频响均达到了设计要求。

SERVO PUMP'S ELECTRICALLY DRIVEN VARIABLE DISPLACEMENT MECHANISM

An electrically driven variable displacement servo pump is designed to meet the requirement of dual-variable control to adjust the motor speed and pump displacement synchronously in integrated electro-hydrostatic actuator(EHA). The electrically driven variable displacement mechanism is designed to replace the hydraulic servo mechanism of the conventional servo pump. The driving force of variable displacement mechanism of the servo pump is analyzed, and a DC servo motor is selected as the executive unit of the variable displacement mechanism, which drives the swashplate directly with a reducing mechanism and a segment gear. The swivel angle of the swashplate is adjusted to change the displacement. The mathematical model is created and the simulation result shows that the displacement of the designed servo pump can be adjusted rapidly without overshoot, the adjusting time and the frequency response under small-signal can meet the system's requirement.