Refrigeration technology is a comprehensive technology that involves multiple disciplines such as thermodynamics, fluid mechanics, and electrical control. It has extensive applications in industries, agriculture, healthcare, and daily life. With the development of technology and social progress, refrigeration technology is constantly innovating and improving. Among them, electronic expansion valves and digitization are important trends and directions in the development of refrigeration technology. They mutually promote and jointly promote the continuous innovation and progress of refrigeration technology.
What is an electronic expansion valve?
Electronic expansion valve is a throttling element that can adjust the refrigerant flow into the refrigeration device according to a preset program. Compared with traditional throttling elements such as capillary tubes and thermal expansion valves, it has higher accuracy, sensitivity, and intelligence, can adapt to different working conditions, and improve the efficiency and reliability of the refrigeration system.
The electronic expansion valve mainly consists of four parts:
Rotor: Equivalent to the rotor of a synchronous motor, it is connected to the valve stem to control the opening size of the valve hole.
Stator: Equivalent to the stator of a synchronous motor; It converts electrical energy into a magnetic field to drive the rotor to rotate.
Valve needle (core): It is driven by the rotor, with a conical end that moves up and down for flow regulation.
Valve body: Generally made of brass.
The working principle of the electronic expansion valve is:
Detect the evaporator outlet pressure and compressor suction superheat through pressure sensors and temperature sensors, and transmit the signal to the controller.
The controller calculates the actual superheat degree based on the signal and compares it with the set superheat degree to obtain the adjustment command.
The controller sends a pulse signal to the drive board based on instructions, and the drive board outputs current to the coil based on the signal.
The coil generates a magnetic field, driving the rotor to rotate, thereby driving the valve needle to move up and down, changing the opening of the valve hole.
The change in valve hole opening affects the size of refrigerant flow, thereby achieving precise control of superheat.
What are the advantages of electronic expansion valves?
Compared to traditional throttling components, electronic expansion valves have the following advantages:
Fast response speed: The electronic expansion valve takes only a few seconds to move from fully closed to fully open, and can respond to changes in system load in a timely manner to avoid overheating or undercooling.
Wide adjustment range: The electronic expansion valve can be accurately adjusted within the range of 10% -100%, and the adjustment range can be set according to the characteristics of different products, which can adapt to various working conditions.
Accurate superheat control: The electronic expansion valve manually sets the superheat degree through the controller, and detects and calculates the superheat degree in real-time through sensors, which can ensure the stability of the superheat degree near the set value and improve the performance and efficiency of the system.
Diverse control functions: The electronic expansion valve can achieve various control logics and methods through the controller, such as startup, shutdown, defrosting, fault protection, etc., increasing the intelligence and reliability of the system.
What is the connection between electronic expansion valves and digitization?
Digitization refers to the process of using digital technology to convert information into digital signals, and storing, processing, transmitting, and displaying them. It can achieve rapid information transmission, convenient management, and diverse applications. The application of digitization in refrigeration technology is mainly reflected in the following aspects:
Digital control system: By using digital devices such as microprocessors, sensors, and actuators, monitoring, controlling, and optimizing the refrigeration system can be achieved, thereby improving the automation level and operational performance of the system.
Digital simulation platform: By establishing a mathematical model of the refrigeration system and using computers for digital simulation analysis, the working principle and characteristics of the system are revealed, providing theoretical basis and technical support for system design, improvement, and fault diagnosis.
Digital information services: By utilizing digital means such as the Internet and mobile communication, remote monitoring, maintenance, and management of refrigeration systems are achieved, providing timely and effective information services and technical support.
There is a close connection between electronic expansion valves and digitization. Electronic expansion valves are an important component of digital control systems, which can adjust the refrigerant flow rate based on digital signals and achieve precise control of parameters such as superheat and pressure. At the same time, electronic expansion valves can also be modeled, analyzed, and optimized through digital simulation platforms to improve their design level and performance. In addition, electronic expansion valves can also be remotely monitored, diagnosed, and adjusted through digital information services, improving their operational reliability and maintenance efficiency.
In short, electronic expansion valves and digitization are important trends and directions in the development of refrigeration technology. They mutually promote and jointly promote the continuous innovation and progress of refrigeration technology.