Screw air compressor frequency converter temperature control system based on PLC

Abstract

The utility model discloses a PLC-based screw air compressor frequency converter temperature control system in the technical field of screw air compressors, and aims to solve the problems that the heat dissipation effect of a frequency converter of a temperature control system in the prior art is poor, and when the temperature of the frequency converter is too high, the frequency converter cannot be protected in time, so that the frequency converter breaks down. The system comprises a plurality of air compressors, each air compressor is provided with a temperature control module and an online protection module, and the air compressors, the temperature control modules and the online protection modules are all electrically connected with a programmable logic controller (PLC); the temperature of the frequency converter is physically adjusted through the cooperation of the air suction device and the air exhaust device, when the physical temperature exchange is not enough to reduce the temperature, the remaining air compressors connected with the air collection device can be started, the operation load of the current air compressors is reduced, control is effectively carried out from the two aspects of heat dissipation and heat production, and the service life of the frequency converter is prolonged. Therefore, the temperature of the frequency converter is greatly reduced, and the frequency converter is protected in time.

Description

Technical Field

[0001] The utility model relates to a PLC-based screw air compressor frequency converter temperature control system, belonging to the technical field of screw air compressors. Background Art

[0002] As an important energy and power supply device for industrial production, air compressors have stability as one of the most important indicators. Screw air compressors are a type of air compressor, available in single-screw and double-screw versions. The invention of twin-screw air compressors was more than a decade later than that of single-screw air compressors, and the design of twin-screw air compressors is more reasonable and advanced. The inverter is the core of the air compressor, and the high temperature problem of the inverter will not only affect its normal performance, but also its service life. If the inverter fails, it will also affect the operation of the entire air compression system.

[0003] The existing screw air compressor inverter temperature control system has a poor heat dissipation effect on the inverter, and when the temperature of the inverter is too high, the inverter cannot be protected in time, which can easily cause the inverter to malfunction and affect the working effect of the device. Utility Model Content

[0004] The purpose of the utility model is to overcome the deficiencies in the prior art and provide a temperature control system for a screw air compressor inverter based on PLC, so as to solve the problem that the temperature control system for the screw air compressor inverter has a poor heat dissipation effect on the inverter, and when the temperature of the inverter is too high, the inverter cannot be protected in time, which easily leads to inverter failure.

[0005] In order to solve the above technical problems, the utility model is implemented by adopting the following technical solutions:

[0006] The utility model provides a PLC-based screw air compressor inverter temperature control system, comprising a plurality of air compressors, wherein the air compressors are provided with a temperature control module and an online protection module, wherein the air compressors, the temperature control module and the online protection module are all electrically connected to a programmable PLC controller, wherein the programmable PLC controller is electrically connected to a data acquisition server, wherein the data acquisition server is electrically connected to a host computer, and the output ends of the plurality of air compressors are provided with a same gas collection device;

[0007] The temperature control module includes a temperature sensor, a pressure sensor, an air intake device, an air exhaust device and two air volume sensors.

[0008] Furthermore, the online protection module includes a flow sensor and an outlet pressure sensor.

[0009] Furthermore, a frequency converter is provided in the air compressor, the air intake device and the exhaust device are arranged on both sides of the outer wall of the air compressor, the temperature sensor and the pressure sensor are arranged inside the air compressor, and the two air volume sensors are respectively arranged on one side of the air intake device and the exhaust device.

[0010] Furthermore, the air intake device, the air exhaust device, the temperature sensor and the pressure sensor are all located on one side of the frequency converter.

[0011] Furthermore, the programmable PLC controller is electrically connected to the temperature sensor, the pressure sensor, the two air volume sensors, the air intake device, the exhaust device, the flow sensor, the air compressor and the outlet pressure sensor respectively.

[0012] Furthermore, the flow sensor is used to detect the outlet air flow of the air compressor, and the outlet air pressure sensor is used to detect the outlet air pressure of the air compressor.

[0013] Furthermore, it also includes an alarm, which is electrically connected to the host computer.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] 1. The PLC-based screw air compressor inverter temperature control system physically adjusts the inverter temperature through the cooperation of the suction device and the exhaust device, ensuring the heat dissipation effect of the inverter. When the physical temperature change is not enough to reduce the temperature, the remaining air compressors connected to the gas collection device can be started to reduce the operating load of the current air compressor, effectively controlling the heat dissipation and heat generation, thereby greatly reducing the inverter temperature, protecting the inverter in time, avoiding inverter failure, ensuring the working effect of the device, and realizing reasonable temperature control of the screw air compressor inverter;

[0016] 2. This PLC-based screw air compressor inverter temperature control system monitors the air output of the exhaust device and the air intake device through the air volume sensor, and monitors the dynamic balance of pressure in the inverter area of ​​the air compressor through the pressure sensor, thereby ensuring the stability of the device operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a connection diagram of a single air compressor, a temperature control module and an online protection module provided according to an embodiment of the utility model;

[0018] Figure 2 It is a connection diagram of multiple air compressors and online protection modules provided according to an embodiment of the utility model;

[0019] Figure 3It is a three-dimensional structural schematic diagram of an air compressor provided according to an embodiment of the utility model;

[0020] Figure 4 It is a flow chart of a control strategy provided according to an embodiment of the utility model.

[0021] In the figure: 1. air compressor; 2. frequency converter; 3. air intake device; 4. exhaust device. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

[0023] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying 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 utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0025] like Figure 1-2As shown, the utility model provides a PLC-based screw air compressor inverter temperature control system, including multiple air compressors 1, the air compressor 1 is provided with a temperature control module and an online protection module, the air compressor 1, the temperature control module and the online protection module are all electrically connected to a programmable PLC controller, the programmable PLC controller is electrically connected to a data acquisition server, the data acquisition server is electrically connected to a host computer, and the output ends of the multiple air compressors 1 are provided with the same gas collection device; the temperature control module includes a temperature sensor, a pressure sensor, an air intake device 3, an exhaust device 4 and two air volume sensors; the online protection module includes a flow sensor and an outlet pressure sensor; the programmable PLC controller is electrically connected to the temperature sensor, the pressure sensor, the two air volume sensors, the air intake device 3, the exhaust device 4, the flow sensor, the air compressor 1 and the outlet pressure sensor respectively.

[0026] Specifically, the host computer can display the current operating status and record the historical records of the equipment operation; specifically, when working, the programmable PLC controller cooperates with the temperature sensor to detect the temperature of the inverter 2. When the temperature of the inverter 2 is high, the programmable PLC controller can control the air intake device 3 and the exhaust device 4 to start working, so that the wind circulates on one side of the inverter 2, thereby having a better heat dissipation effect on the inverter 2. The programmable PLC controller cooperates with the air volume sensor and the pressure sensor to monitor and maintain the dynamic balance of pressure in the inverter area based on the data of the air volume sensor and the pressure sensor, thereby ensuring the stability of the device when working; when the temperature of the inverter 2 is too high, since the output ends of the multiple air compressors 1 are provided with the same gas collection device, when the ventilation volume of the gas collection device remains unchanged, the programmable PLC controller can control the remaining air compressors 1 to work, thereby sharing the operating load of the original air compressor 1, so that the working intensity of the original inverter 2 is reduced, thereby greatly reducing the temperature of the inverter 2, and timely protecting the inverter 2 to avoid failure of the inverter 2, thereby ensuring the working effect of the device.

[0027] The utility model physically adjusts the temperature of the inverter 2 by cooperating with the air intake device 3 and the exhaust device 4, thereby ensuring the heat dissipation effect of the inverter 2. When the physical temperature exchange is not enough to reduce the temperature, the remaining air compressor 1 connected to the gas collection device can be started to reduce the operating load of the current air compressor 1, effectively controlling the heat dissipation and heat generation, thereby greatly reducing the temperature of the inverter 2, protecting the inverter 2 in time, avoiding malfunction of the inverter 2, ensuring the working effect of the device, and realizing reasonable temperature control of the screw air compressor inverter.

[0028] like Figure 3As shown, in one embodiment, a frequency converter 2 is provided in the air compressor 1, the air intake device 3 and the exhaust device 4 are arranged on both sides of the outer wall of the air compressor 1, the temperature sensor and the pressure sensor are arranged inside the air compressor 1, and the two air volume sensors are respectively arranged on one side of the air intake device 3 and the exhaust device 4, and the air intake device 3, the exhaust device 4, the temperature sensor and the pressure sensor are all located on one side of the frequency converter 2.

[0029] Specifically, the air intake device 3 and the exhaust device 4 are arranged on one side of the frequency converter 2 to ensure that the wind can pass through the frequency converter 2 when circulating, thereby ensuring the heat dissipation effect of the wind on its frequency converter 2. The air intake device 3 and the exhaust device 4 adopt frequency conversion control, and the air volume sensor is used to monitor the air output of the exhaust device 4 and the air intake device 3. The pressure sensor is used to monitor the dynamic balance of pressure in the frequency converter 2 area in the air compressor 1, thereby ensuring the stability of the device operation.

[0030] In one embodiment, the flow sensor is used to detect the outlet flow rate of the air compressor 1, and the outlet pressure sensor is used to detect the outlet pressure of the air compressor 1. An alarm is also included, and the alarm is electrically connected to the host computer.

[0031] Specifically, the host computer can display the temperature control related parameters of the inverter 2 and issue an alarm prompt; the online control module connects the outlet pressure sensor and flow sensor to the programmable PLC controller, and performs online control in combination with the preset control algorithm. The specific control strategy is: Figure 4 As shown, when it is monitored that the temperature of the frequency converter 2 exceeds the first threshold, the preset control algorithm is used to automatically adjust the operating status of the air intake device 3 and the exhaust device 4, the frequency conversion adjustment is performed according to the heat dissipation effect of the frequency converter 2 area, and the pressure dynamic balance of the frequency converter 2 area is monitored and maintained according to the data of the air volume sensor and the pressure sensor; when it is monitored that the temperature of the frequency converter 2 is higher than the first threshold and lower than the second threshold, and then when the detected air flow reaches the air outlet threshold of the air compressor 1, and the air outlet pressure drops to the set value, the remaining air compressors 1 are started through the programmable PLC controller; when it is monitored that the temperature of the frequency converter 2 is higher than the second threshold, the remaining air compressors 1 are started immediately, thereby reducing the operating load of the current air compressor 1; wherein, Figure 4 "Y" in the formula represents yes, and "N" represents no; the first threshold value, the second threshold value, the gas outlet threshold value and the set value are all preset values.

[0032] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A PLC-based screw air compressor inverter temperature control system, characterized in that: It includes a plurality of air compressors, each of which is provided with a temperature control module and an online protection module, the air compressor, the temperature control module and the online protection module are all electrically connected to a programmable PLC controller, the programmable PLC controller is electrically connected to a data acquisition server, the data acquisition server is electrically connected to a host computer, and the output ends of the plurality of air compressors are provided with a same gas collection device; The temperature control module includes a temperature sensor, a pressure sensor, an air intake device, an air exhaust device and two air volume sensors.

2. The PLC-based screw air compressor inverter temperature control system according to claim 1 is characterized in that: The online protection module includes a flow sensor and an outlet pressure sensor.

3. The PLC-based screw air compressor inverter temperature control system according to claim 1 is characterized in that: A frequency converter is provided in the air compressor, the air intake device and the exhaust device are arranged on both sides of the outer wall of the air compressor, the temperature sensor and the pressure sensor are arranged inside the air compressor, and the two air volume sensors are respectively arranged on one side of the air intake device and the exhaust device.

4. The PLC-based screw air compressor inverter temperature control system according to claim 3 is characterized in that: The air intake device, the air exhaust device, the temperature sensor and the pressure sensor are all located on one side of the frequency converter.

5. The PLC-based screw air compressor inverter temperature control system according to claim 2, characterized in that: The programmable PLC controller is electrically connected to the temperature sensor, the pressure sensor, the two air volume sensors, the air intake device, the air exhaust device, the flow sensor, the air compressor and the air outlet pressure sensor respectively.

6. The PLC-based screw air compressor inverter temperature control system according to claim 2, characterized in that: The flow sensor is used to detect the outlet air flow of the air compressor, and the outlet air pressure sensor is used to detect the outlet air pressure of the air compressor.

7. The PLC-based screw air compressor inverter temperature control system according to claim 1, characterized in that: It also includes an alarm, which is electrically connected to the host computer.

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