基于单片机的湿度测量控制仪2014.docVIP

摘 要 本设计为一种以AT89C51单片机和HS1101湿度传感器为核心的湿度控制系统。该系统可以实时检测湿度值显示出来并可以进行控制。硬件电路主要包括AT89C51单片机最小系统，测湿电路、时钟电路、数码显示电路、键盘处理电路以及控制电路等,本机选择高精度的HS1101电容式湿度传感器，当环境湿度发生变化时，湿度传感器的电容随着湿度的变化而变化，然后将变化的电容通过转换电路转换为与之对应变化的频率，频率经过光耦电路消除杂波后送入到单片机中，单片机对采集到的信号进行运算并通过查表得到相应的湿度值，之后通过单片机的外部接口电路显示该湿度值。本机可以通过键盘设定湿度值，中央控制系统将设定值与检测值进行比较，检测值低于设定值的话，控制系统就会通过继电器接通电路进行加湿。与传统的测试方法相比，本湿度控制系统具有可靠性高、精度高、性价比高等优点。适合湿度的自动测量和控制，使设备和系统运行在最佳状态，从而保证生产、生活的高效、舒适。 关键词：单片机；湿度；自动控制；HS1101 ABSTRACT In this paper The design is based on AT89C51 MCU and HS1101 humidity sensor as the core of the humidity control system. The system can real-time detect the humidity values are displayed and can be controlled. The hardware circuit mainly includes AT89C51 minimum system microcontroller, humidity measurement circuit, clock circuit, digital display circuit, keyboard circuit and control circuit etc., The selection of HS1101 capacitive humidity sensor with high accuracy, when the environmental temperature changes, capacitive humidity sensor varies with humidity changes, then the change in capacitance through the corresponding conversion circuit for converting and changing frequency, frequency through the optocoupler circuits eliminate clutter into to the MCU, signal microcontroller acquisition of the operation and the look-up table to obtain the corresponding humidity, the humidity value is displayed through the external interface circuit of scm. The humidity value can be set through the keyboard, central control system will set the value was compared with test value, the value is lower than the set value of detection, control system will be connected to the circuit by the relay. Compared with the conventional testing method, the humidity control system has high reliability, high precision, high cost-effective advantages. Automatic measurement and control for the humidity, the equipment and the system run in the best condition, in order to ensure the production, efficient, comfortable life. Key words： SCM；Humidity；automatic con