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高精度微量恒流泵控制器主要用来控制HW型微量恒流泵,也适用于以步进电机为动力的各种装置。HW型微量恒流泵适用于化学反应动力学、液相色谱技术以及其他多种研究工作。它的特点是排液流量十分微小(2微升/分),最小可调节流量值亦十分微小(±1微升/分)。控制器的任务是根据所要求(设定)的排液流量,发生相应频率的脉冲,控制步进电机的转速,使泵按照设定流量值恒定地排液。因此,控制器发生的脉冲应满足:(1)频率极其稳定;(2)脉冲宽度和间隔均匀;(3)频率应能作精细的调整,以适合最小可调节流量(相应的频率变化量为±0.71赫兹)的需要。能否达到这些基本要求是控制的关键。步进电机控制电路的种类很多,如驰张振荡器、压控振荡器、各种稳态电路、波形发生电路、晶体振荡分频电路。这些电路都属于开环
High-precision micro-constant current pump controller is mainly used to control the HW-type constant current pump, but also for a variety of devices powered by stepper motors. HW-type constant current pump for chemical reaction kinetics, liquid chromatography technology and a variety of other research work. It features a very small discharge flow (2 μl / min) and a very small minimum flow (± 1 μl / min). The controller’s task is based on the required (set) of the discharge flow, the corresponding frequency pulse occurs, the control stepper motor speed, the pump constant flow in accordance with the set value flow. Therefore, the pulse generated by the controller should be: (1) the frequency is extremely stable; (2) the pulse width and spacing are uniform; (3) the frequency should be finely tuned to suit the minimum adjustable flow (the corresponding frequency change is ± 0.71 Hz) needs. Whether to meet these basic requirements is the key to control. Stepper motor control circuit of many different types, such as Chi Zhang oscillator, voltage-controlled oscillator, a variety of steady-state circuits, waveform generation circuit, crystal oscillator frequency divider circuit. These circuits are open-loop