Overall Design of Granary Temperature and Humidity Control System

Overall Design of Granary Temperature and Humidity Control System

The grain environment is an important aspect of food security. With the advancement of science and technology, the measurement and control system of the granary environment has begun to be widely used in practice and plays an important and important role in ensuring food security. With the continuous advancement of agricultural production technology, advanced facilities are widely used in various aspects of agriculture. Traditional granary environment management adopts analog control instruments and manual management methods, and its backward management method can no longer adapt to the development of current agricultural technology. For this purpose, SCM is used to control and manage the temperature, humidity, and pests of the granaries, and the automatic measurement and management of granary environment measurement and management are realized. Temperature and humidity self-recording instrument is one of the commonly used instruments for measuring temperature and humidity.

The entire measurement and control system consists of single chip AT89S51 as the core, together with temperature, humidity detection and transmission circuit, temperature transmission circuit, clock circuit, keyboard and LED display circuit and power supply circuit and other components. The system is divided into two parts, including input and output circuits. The input circuit is the sampling granary environmental data, including temperature, humidity measurement, and the necessary data conversion circuit; the keyboard is used as the most basic input circuit for inputting the execution parameters of the MCU to control the motor of the ventilation equipment. The output circuit includes LED display and ventilation equipment. The smaller number of LEDs is subject to the measurement accuracy of the sensor itself and the processing precision of the single-chip microcomputer and displays the current measured temperature and humidity. The self-recording thermometer and hygrometer is also a design that includes a temperature sensor and a humidity sensor, and the LCD screen displays the current temperature and humidity. When the system parameters are entered using the keyboard, the input parameter values ​​are displayed; the main control object of the ventilation equipment is the motor, auxiliary and necessary digital control circuit, used to improve the granary environment. These two belong to different modules and are combined together with the SCM to complete the overall measurement and control system of the granary. The measurement and control system first needs a certain support system to run the system and ensure the correct execution and stability of the system. These circuit modules include a reset circuit, a power supply circuit, and a clock control circuit. The system parameters can be manually set by humans, so a keyboard circuit interface is required for inputting the operating parameters of the system. In order to complete the granary environmental measurement task, the sensor is required to input the temperature to the MCU, which includes a temperature detection and humidity detection circuit. The measurement results of the system environment and the adjustment system parameters need to be displayed for user interaction. This part belongs to the display circuit. Finally changing the granary environment requires the ventilator to exchange gas with the external environment to produce air convection, which is controlled by the blower and exhaust fan. The control mechanisms of these two devices are the same, so any one of them can be used to change the system environment. In addition, the wind speed in the air can be measured by the wind anemometer. The wind anemometer is designed to determine the wind speed and direction.