一种新的连续性血液净化设备滚压泵直流电机驱动方法

A New Circuit for DC Motor Driver Applied in Roller Pump in Continuous Renal Replacement Therapy

根据实际连续性血液净化设备(CRRT),选用滚压式血泵和直流电机搭建试验平台,按照CRRT机对血液流率、流速可调和长时间稳定要求,采用LM2678设计接口简单、易于控制的滚压式血泵直流电机新型功率驱动电路。由试验数据得到功率驱动电路在空载和带负载时输入、输出电压特性曲线(分3个工作区);采用线性回归方法,分别构建正常工作(线性区)时这两种情况下系统特性的拟合曲线方程。试验结果表明:新型功率驱动电路的输入电压和输出电压具有良好线性关系,通过改变驱动电路输出电压,稳定调节直流电机转速,从而实现调节CRRT血泵流量。

According to the practical applications of continuous renal replacement therapy（CRRT） equipment, the relier pump and DC motor were chosen to structure the test platform. In accordance with the requirements of CRRT machine on the range of blood flow rate, the adjustability of speed of blood flow and the long- time working stability, a new power driving circuit for DC motor driving relier pump was designed using LM2678, which was with simple interface and easy to control. The input and output voltage characteristic curves （divided into three working fields） of the circuit were drawn by test data under load and unload cases, respectively. The curves fitting equations with the system properties under normal working condition （linear region） for the two cases were established respectively, which used linear regression methods. The experimental results show that the new power driving circuit has a good linear relationship between the input and the output voltages. By adjusting the output voltage of driving circuit, the speed of reliable and stable regulation DC motor is achieved, thus the flow regulation for CRRT blood pump is also realized.