Electronic expansion valve controller

Abstract

The utility model discloses an electronic expansion valve controller which is electrically connected with a temperature measuring element through an RTD acquisition unit circuit to receive temperature signals in real time, a CPU control module compares the obtained actual temperature of a temperature test box with a preset temperature, and when the actual temperature of the temperature test box has a large deviation with the preset temperature, the CPU control module controls the electronic expansion valve to operate. The CPU control module adjusts the output of the heater by adjusting the solid-state output, so that the purpose of controlling the temperature in the temperature test box is achieved; the CPU control module is in communication connection with the EM300 communication module through the RS485 interface, and the EM300 communication module is electrically connected with the electronic expansion valve, so that the opening degree of the electronic expansion valve can be rapidly and dynamically adjusted according to the deviation value of the set temperature and the actual temperature in the temperature test box, the response speed and stability of a compressor are improved, and the service life of the compressor is prolonged. And the system can quickly adapt to various operation conditions and load changes.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic expansion valve control, and more specifically to an electronic expansion valve controller. Background Art

[0002] The electronic expansion valve is a throttling element that can adjust the refrigerant flow entering the refrigeration unit according to a preset program. In some occasions where the load changes drastically or the operating conditions are wide, traditional throttling elements (such as capillary tubes, thermal expansion valves, etc.) can no longer meet the requirements of comfort and energy saving. Electronic expansion valves combined with compressor variable capacity technology have been increasingly widely used. At present, the research on electronic expansion valves generally includes three directions: application research, flow characteristics, control strategies and algorithms.

[0003] As a new type of control element, the electronic expansion valve has become an important part of the intelligentization of the refrigeration system, and an important means and guarantee for the real realization of the optimization of the refrigeration system. It is used in more and more fields. The application of electronic expansion valves will become more mature with the advancement and development of technology.

[0004] Since the electronic expansion valve is one of the key components of the refrigeration system, the control quality of the opening degree of the electronic expansion valve is the key to determine the refrigeration performance, and has a great impact on the stability, safety and economy of the entire refrigeration system. The electronic expansion valve controller is used as a controller for the temperature test chamber. It is mainly used for regulating the electronic expansion valve of the refrigeration system. It can intelligently adjust the cooling output of the compressor and can accurately control the opening degree of the electronic expansion valve under different operating conditions to control the refrigeration flow.

[0005] Traditionally, temperature control and electronic expansion valve control are two independent control systems in refrigeration systems. This separate control method may cause signal transmission delays and errors, affecting the response speed and stability of the system. Utility Model Content

[0006] In order to overcome the deficiencies of the prior art, the utility model provides an electronic expansion valve controller, which can realize accurate and efficient control of a refrigeration system by integrating temperature control and electronic expansion valve control, and realize accurate and efficient control of the exhaust temperature of a compressor, and control it at a temperature value, which not only protects the compressor from damage, but also facilitates the efficient output of the compressor; moreover, the opening of the electronic expansion valve can be quickly and dynamically adjusted according to the set temperature and the actual temperature difference, so that the opening of the electronic expansion valve varies between 0 and 100%, thereby reducing signal transmission delays and errors, thereby improving the response speed and stability of the compressor, and enabling it to quickly adapt to various operating conditions and load changes.

[0007] The technical solution of the utility model is as follows: an electronic expansion valve controller, comprising a shell and a CPU control module, an EM300 communication module and an RTD acquisition unit circuit arranged in the shell, the CPU control module is electrically connected to a temperature measuring element through the RTD acquisition unit circuit, the EM300 communication module is communicatively connected to the CPU control module through an RS485 interface, and the EM300 communication module is electrically connected to the electronic expansion valve.

[0008] Furthermore, it also includes an AI acquisition module, which is electrically connected to the pressure sensor and is communicatively connected to the CPU control module via an RS485 interface.

[0009] Furthermore, it also includes a touch screen, which is communicatively connected to the CPU control module via an RS485 interface.

[0010] Furthermore, the RTD acquisition unit circuit includes an RTD digital converter, a signal input end of the RTD digital converter is used to connect to a temperature measurement element, and a signal output end of the RTD acquisition unit circuit is electrically connected to a signal input end of the CPU control module.

[0011] Furthermore, the AI ​​acquisition module is a data acquisition interface module with 8 analog inputs.

[0012] Furthermore, the CPU control module is an S7-200 programmable controller.

[0013] Furthermore, the length of the shell is 200.4 mm, and the width of the shell is 146.5 mm.

[0014] Furthermore, the thickness of the shell is 34 mm.

[0015] Furthermore, the touch screen is arranged on the front end surface of the shell, and the touch screen is located in the middle of the front end surface of the shell.

[0016] The utility model according to the above scheme has the following beneficial effects: the utility model provides an electronic expansion valve controller, which is electrically connected to the temperature measuring element through the RTD acquisition unit circuit, and receives the temperature signal in real time. At the same time, the RTD acquisition unit circuit converts the analog signal of the temperature measuring element into a digital signal so that the CPU control module can read and analyze it quickly. The CPU control module compares the actual temperature of the temperature test chamber obtained with the preset temperature. When there is a large deviation between the actual temperature of the temperature test chamber and the preset temperature, the CPU control module adjusts the heater output by adjusting the solid-state output, thereby achieving the purpose of controlling the temperature in the temperature test chamber; secondly The CPU control module is connected to the EM300 communication module through the RS485 interface, and the EM300 communication module is electrically connected to the electronic expansion valve. Through the RS485 interface, the CPU control module and the EM300 communication module can achieve fast and stable data exchange, including control instructions, status information, temperature data, etc. This efficient data transmission ensures the real-time and response speed of the control system, so that the opening of the electronic expansion valve can be quickly and dynamically adjusted according to the deviation between the set temperature and the actual temperature in the temperature test chamber, thereby improving the response speed and stability of the compressor, so that it can quickly adapt to various operating conditions and load changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the working principle of an electronic expansion valve controller in an embodiment of the utility model;

[0019] Figure 2 This is a control flow diagram of an electronic expansion valve controller in an embodiment of the utility model;

[0020] Figure 3 This is a schematic diagram of the port wiring of the CPU control module in the embodiment of the utility model;

[0021] Figure 4 This is a schematic diagram of the port wiring of the EM300 communication module in the embodiment of the utility model;

[0022] Figure 5 This is a schematic diagram of the port wiring of the AI ​​acquisition module in the embodiment of the utility model;

[0023] Figure 6It is a structural schematic diagram of an electronic expansion valve controller in an embodiment of the utility model.

[0024] In the figure, 1. housing; 2. touch screen. DETAILED DESCRIPTION

[0025] The following detailed description and drawings of the embodiments of the present invention are used to illustrate the principle of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the embodiments described.

[0026] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0027] See also Figure 1 to Figure 6 As shown, an embodiment of the utility model provides an electronic expansion valve controller, including a shell 1 and a CPU control module, an EM300 communication module and an RTD acquisition unit circuit arranged in the shell 1, the CPU control module is electrically connected to the temperature measuring element through the RTD acquisition unit circuit, the EM300 communication module is communicatively connected to the CPU control module through an RS485 interface, and the EM300 communication module is electrically connected to the electronic expansion valve, wherein the CPU control module is an S7-200 programmable controller.

[0028] Specifically, an electronic expansion valve controller provided by an embodiment of the utility model, through the RTD acquisition unit circuit, the CPU control module can receive the temperature signal transmitted by the temperature measuring element in real time, the RTD acquisition unit circuit converts the analog signal into a digital signal, so that the CPU control module can quickly read and analyze the actual temperature value, the CPU control module compares the actual temperature of the temperature test box obtained with the preset temperature, when the actual temperature of the temperature test box has a large deviation from the preset temperature, the CPU control module adjusts the heater output by adjusting the solid-state output, thereby achieving the purpose of controlling the temperature in the temperature test box; secondly, the CPU control module is connected to the EM300 communication module through the RS485 interface, and the EM300 communication module is electrically connected to the electronic expansion valve. Through the RS485 interface, the CPU control module and the EM300 communication module can realize fast and stable data exchange, including control instructions, status information, temperature data, etc., such efficient data transmission ensures the real-time and response speed of the control system, so that the opening of the electronic expansion valve can be quickly and dynamically adjusted according to the deviation value between the set temperature and the actual temperature in the temperature test box, thereby improving the response speed and stability of the compressor, so that it can quickly adapt to various operating conditions and load changes.

[0029] Preferably, an electronic expansion valve controller provided by an embodiment of the utility model further includes an AI acquisition module, which is electrically connected to the pressure sensor, and the AI ​​acquisition module is communicatively connected to the CPU control module via an RS485 interface. Specifically, the 8AI acquisition module is a data acquisition interface module with 8 analog inputs, which is used to acquire, convert and process analog signals, and output the processed digital signals to the CPU control module for further analysis and processing.

[0030] Specifically, the 8AI acquisition module includes analog signal input circuit, A / D conversion circuit, digital signal processing circuit and communication interface. The analog signal input circuit is responsible for receiving external analog signals and converting them into signals suitable for processing by the A / D conversion circuit; the A / D conversion circuit converts analog signals into digital signals; the digital signal processing circuit further processes and filters the converted digital signals to improve the accuracy and stability of the signals; the communication interface is responsible for outputting the processed digital signals to the CPU control module.

[0031] Preferably, an electronic expansion valve controller provided by an embodiment of the utility model also includes a touch screen 2, which is communicatively connected to the CPU control module via an RS485 interface, and the touch screen 2 is arranged on the front end surface of the shell 1, and the touch screen 2 is located in the middle position of the front end surface of the shell 1.

[0032] Preferably, the RTD acquisition unit circuit includes an RTD digital converter, a signal input end of the RTD digital converter is used to connect to the temperature measurement element, and a signal output end of the RTD acquisition unit circuit is electrically connected to a signal input end of the CPU control module.

[0033] Preferably, the length of the housing 1 is 200.4 mm, and the width of the housing 1 is 146.5 mm.

[0034] Preferably, the thickness of the housing 1 is 34 mm.

[0035] In this embodiment, the compressor of the temperature test chamber includes a cold-side electronic expansion valve and a main cold-side electronic expansion valve. The cold-side electronic expansion valve dynamically adjusts its opening according to the suction and exhaust temperatures of the compressor. Specifically, the cold-side electronic expansion valve dynamically adjusts its opening according to the suction and exhaust temperatures of the compressor and according to temperature changes, thereby optimizing the flow rate of the refrigerant, helping to control the exhaust temperature of the compressor, and preventing damage caused by overheating, which can improve the energy efficiency of the system and extend the service life of the compressor. The main cold-side electronic expansion valve is used to control the temperature inside the temperature test chamber. According to the difference between the set temperature and the actual temperature inside the temperature test chamber, its opening is dynamically adjusted to accurately control the flow rate of the refrigerant and achieve precise control of the temperature inside the chamber. This control method not only improves the accuracy of temperature control, but also helps to reduce unnecessary energy consumption and achieve more energy-saving operation.

[0036] The indicated orientation or position relationship is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when used, or the orientation or position relationship commonly understood by technical personnel in this field, or the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to the utility model.

[0038] The above is an exemplary description of the utility model patent in conjunction with the accompanying drawings. It is obvious that the implementation of the utility model patent is not limited to the above-mentioned method. As long as various improvements are made by adopting the method concept and technical solution of the utility model patent, or the concept and technical solution of the utility model patent are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.

Claims

1. An electronic expansion valve controller, characterized in that: The invention comprises: a shell, a CPU control module, an EM300 communication module and an RTD acquisition unit circuit arranged in the shell, wherein the CPU control module is electrically connected to the temperature measuring element through the RTD acquisition unit circuit, the RTD acquisition unit circuit converts the analog signal into a digital signal, so that the CPU control module reads and analyzes the actual temperature value, the CPU control module compares the acquired actual temperature of the temperature test box with the preset temperature, and when there is a deviation between the actual temperature of the temperature test box and the preset temperature, the CPU control module adjusts the heater output by adjusting the solid-state output to control the temperature in the temperature test box; the EM300 communication module is connected to the CPU control module through the RS485 interface for communication, and the EM300 communication module is electrically connected to the electronic expansion valve; when there is a deviation between the actual temperature of the temperature test box and the preset temperature, the CPU control module sends a control instruction to the EM300 communication module through the RS485 interface to adjust the opening of the electronic expansion valve.

2. An electronic expansion valve controller as claimed in claim 1, characterized in that: It also includes an AI acquisition module, which is electrically connected to the pressure sensor and is communicatively connected to the CPU control module via an RS485 interface.

3. An electronic expansion valve controller as claimed in claim 1, characterized in that: It also includes a touch screen, which is communicatively connected with the CPU control module via an RS485 interface.

4. An electronic expansion valve controller as claimed in claim 2, characterized in that: The AI ​​acquisition module is a data acquisition interface module with 8 analog inputs.

5. An electronic expansion valve controller as claimed in claim 1, characterized in that: The CPU control module is an S7-200 programmable controller.

6. An electronic expansion valve controller as claimed in claim 1, characterized in that: The length of the shell is 200.4 mm, and the width of the shell is 146.5 mm.

7. An electronic expansion valve controller as claimed in claim 1, characterized in that: The thickness of the shell is 34 mm.

8. An electronic expansion valve controller as claimed in claim 3, characterized in that: The touch screen is arranged on the front end surface of the shell, and the touch screen is located in the middle of the front end surface of the shell.

Images