基于频率曲线优化的蠕动泵精确定容方法

Peristaltic pump accurate constant volume method based on frequency curve optimization

针对蠕动泵快速定容小流量、低流速、高粘性流体时出现气液共存导致精度低的问题,提出了一种基于电机频率曲线的蠕动泵的精确定容方法。首先对蠕动泵实验装置进行工作原理分析,建立了目标容量与电机驱动频率关系模型,并针对电机驱动频率曲线的不连续导致气泡产生的现象,提出了一种具有误差补偿的抛物线加减速曲线的电机驱动频率模型;然后对该模型参数进行辨识,并选择样本集外的容量进行在线验证;最后将所提方法与无误差补偿的抛物线加减速曲线、匀加减速曲线以及指数型加减速曲线的频率控制方法进行了对比分析。实验结果表明,该模型精度分别提高了83.05%、41.18%和28.57%,最大相对误差0.9%,平均相对误差0.5%,验证了所提方法的正确性和可行性。

Aiming at the problem that the gas-liquid coexistence leads to low precision due to the peristaltic pump has a low volume, low flow rate and high viscous fluid, a precise determination method of the peristaltic pump based on the motor frequency curve is proposed. Firstly, by analyzing the working principle of the peristaltic pump, the relationship model between target capacity and driving frequency of motor is established. Aiming at the phenomenon that the discontinuity of the driving frequency curve of the motor motor leads to bubble generation, a driving frequency model of the motor with error compensation and parabola acceleration and deceleration curve is proposed. Then the model parameters are identified, and the volume outside the sample set is also selected for on-line verification. Finally, the proposed method is compared with the frequency control method of the parabola, uniform, exponential acceleration and deceleration curve respectively without error compensation. The experimental results show that the accuracy of the model is increased by 83.05%, 41.18% and 28.57%. The maximum relative error is 0.9%, and the average relative error is 0.5%, which verifies the correctness and feasibility of the proposed method.