CN-122028318-A - PCB cooling control method and system based on real-time temperature sensing

CN122028318ACN 122028318 ACN122028318 ACN 122028318ACN-122028318-A

Abstract

The application relates to the technical field of PCB cooling, and discloses a PCB cooling control method and a PCB cooling control system based on real-time temperature sensing, wherein the method comprises the steps of acquiring temperature monitoring data and position information of a plurality of PCBs; the method comprises the steps of determining a temperature abnormal region, analyzing a temperature change trend of a continuous time point, identifying an overheating region based on the temperature abnormal region and the temperature change trend, marking space coordinates of the overheating region, determining a temperature change rate of the overheating region, generating temperature evaluation data, determining a cooling demand intensity value of each cooling region according to the space coordinates and the temperature evaluation data, generating a cooling control instruction, acquiring outlet temperature data of a PCB at an outlet, and correcting operation parameters of each cooling region when the outlet temperature data exceeds a safe temperature threshold value. The application improves the cooling uniformity and reduces the risks of plate warpage and welding spot damage caused by thermal stress.

Inventors

Luo Bingqin
LIANG ZHENHUA
JIANG HUI

Assignees

深圳市永信达科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260330

Claims (10)

1. A PCB cooling control method based on real-time temperature sensing is characterized by comprising the following steps: acquiring temperature monitoring data and position information of a plurality of PCBs; The method comprises the steps of monitoring temperature monitoring data, carrying out temperature field spatial gradient calculation according to the temperature monitoring data, determining a temperature abnormal region, analyzing the temperature change trend of continuous time points, identifying an overheating region based on the temperature abnormal region and the temperature change trend, marking the spatial coordinates of the overheating region, determining the temperature change rate of the overheating region, and generating temperature evaluation data according to the area occupation ratio of the overheating region and the temperature change rate; Determining a cooling demand intensity value of each cooling area according to the space coordinates and the temperature evaluation data, and adjusting the operation parameters of each cooling area based on the cooling demand intensity value to generate a cooling control instruction; and acquiring outlet temperature data of the PCB at the outlet, determining a temperature deviation value according to the historical cooling effect data and the PCB moving speed when the outlet temperature data exceeds a safety temperature threshold, and correcting the operation parameters of each cooling area according to the temperature deviation value.
2. The PCB cooling control method of claim 1, wherein identifying an overheating zone, marking spatial coordinates of the overheating zone, and determining a rate of temperature change of the overheating zone comprises: when the temperature value of the temperature abnormal region exceeds a high temperature threshold value and the slope of the temperature change trend is larger than a rising rate threshold value, judging that the current region is an overheat region; Acquiring boundary point positions of the overheat areas based on a coordinate system of the PCB, and determining vertex coordinates of the minimum circumscribed rectangle as the space coordinates; and determining the temperature change rate according to the temperature time sequence of the overheat area.
3. The PCB cooling control method based on real-time temperature sensing of claim 2, wherein generating the temperature evaluation data comprises: Determining the area of the overheat area and determining the area occupation ratio based on the physical size of the PCB and the space coordinates; The method includes determining a range level of the superheat region based on the area duty, determining a speed level of a temperature rise based on the temperature change rate, and generating the temperature evaluation data based on the range level and the speed level.
4. The PCB cooling control method based on real-time temperature sensing of claim 3, wherein determining the cooling demand intensity value of each cooling area includes: The method comprises the steps of mapping the overheating areas into cooling areas based on space coordinates, determining basic cooling intensity according to risk levels in temperature evaluation data, determining cooling response time according to the moving speed of a PCB, and determining the cooling demand intensity value of each cooling area according to the basic cooling intensity and the cooling response time.
5. The PCB cooling control method based on real-time temperature sensing of claim 1, wherein determining the temperature deviation value comprises: The method comprises the steps of obtaining expected outlet temperature under the same working condition in historical cooling effect data, comparing the expected outlet temperature with actual outlet temperature to determine basic temperature deviation, determining temperature adjustment advance according to the moving speed of a PCB and the length of a cooling area, and determining the temperature deviation value according to the basic temperature deviation and the temperature adjustment advance.
6. The PCB cooling control method of claim 5, wherein when correcting the operation parameters of each cooling area according to the temperature deviation value, comprising: the method comprises the steps of distributing the temperature deviation value to each cooling area in proportion, determining parameter adjustment quantity according to the proportion distributed to each cooling area, and correcting the fan rotating speed, the cooling fluid flow and the air duct guide angle of each cooling area based on the parameter adjustment quantity.
7. The PCB cooling control method of claim 1, wherein when obtaining temperature monitoring data and position information of a plurality of PCBs, comprising: Collecting temperature monitoring data of the surface of the PCB through a temperature sensor array arranged along the conveyor belt; and acquiring the position information of the PCB in the moving process through a position encoder arranged along the conveyor belt.
8. The PCB cooling control method of claim 7, wherein when obtaining temperature monitoring data and position information of a plurality of PCBs, further comprising: And carrying out time synchronization processing on the temperature monitoring data and the position information.
9. The PCB cooling control method of claim 8, wherein determining the temperature anomaly region comprises: The method comprises the steps of constructing a temperature distribution matrix on the surface of a PCB (printed circuit board) based on the spatial distribution of the temperature sensor array, determining a temperature spatial change rate according to the temperature difference value between adjacent position points in the temperature distribution matrix, determining a temperature gradient vector and a module value thereof according to the temperature spatial change rate, comparing the module value of the temperature gradient vector with a gradient threshold value, and determining the current area as a temperature abnormal area when the module value of the temperature gradient vector exceeds the gradient threshold value.
10. A PCB cooling control system based on real-time temperature sensing, for applying the PCB cooling control method based on real-time temperature sensing according to any one of claims 1 to 9, comprising: The data acquisition unit is configured to acquire temperature monitoring data and position information of a plurality of PCBs; An abnormality evaluation unit configured to perform temperature field spatial gradient calculation according to the temperature monitoring data, determine a temperature abnormality region, analyze a temperature variation trend of successive time points, identify an overheat region based on the temperature abnormality region and the temperature variation trend, mark spatial coordinates of the overheat region, and determine a temperature variation rate of the overheat region; the instruction regulation and control unit is configured to determine the cooling demand intensity value of each cooling area according to the space coordinates and the temperature evaluation data, adjust the operation parameters of each cooling area based on the cooling demand intensity value and generate a cooling control instruction; And the operation correction unit is configured to acquire outlet temperature data of the PCB at the outlet, determine a temperature deviation value according to the historical cooling effect data and the PCB moving speed when the outlet temperature data exceeds a safe temperature threshold, and correct the operation parameters of each cooling area according to the temperature deviation value.

Description

PCB cooling control method and system based on real-time temperature sensing Technical Field The invention relates to the technical field of PCB cooling, in particular to a PCB cooling control method and system based on real-time temperature sensing. Background In the manufacturing process of a Printed Circuit Board (PCB), a rapid and uniform cooling process is required to be performed on the PCB after high temperature processes such as reflow soldering and wave soldering. The link is important to ensure the welding quality, inhibit the warpage of the plate, the cracking of the welding spot and the thermal damage of the components caused by the thermal stress, and directly influence the yield and the long-term reliability of the product. With the development of electronic products to high density, miniaturization and multifunction, the layout of components on a PCB is increasingly complex, the problem of uneven heat load distribution is remarkable, and higher requirements are put on the accuracy and adaptability of the cooling process. In the current cooling control scheme of the main stream in industry, a forced air cooling or liquid cooling system with fixed parameters is mostly adopted, for example, a constant-rotation-speed fan array or a fixed-flow cooling nozzle is configured at a cooling station, and global regulation is performed according to preset time or global average temperature. Part of the schemes are introduced into a thermal infrared imager or a distributed temperature sensor for monitoring, and the cooling intensity adjustment is triggered by combining a simple threshold. However, the existing cooling control technology has obvious defects of weak space sensing capability, difficulty in accurately positioning local hot spots and temperature gradients, passive response mechanism, lack of temperature change trend pre-judgment, no combination of PCB moving speed and position dynamic matching cooling action, space-time mismatch, feedback correction dependence on a simple algorithm, easiness in causing overshoot or oscillation, insufficient temperature and position data synchronization precision, and influence on control reliability and cooling uniformity. Therefore, it is necessary to design a PCB cooling control method and system based on real-time temperature sensing to solve the problems in the prior art. Disclosure of Invention In view of the above, the invention provides a PCB cooling control method and a system based on real-time temperature sensing, which aim to solve the problems of poor reliability and low cooling uniformity of PCB cooling control. In one aspect, the invention provides a PCB cooling control method based on real-time temperature sensing, which comprises the following steps: acquiring temperature monitoring data and position information of a plurality of PCBs; The method comprises the steps of monitoring temperature monitoring data, carrying out temperature field spatial gradient calculation according to the temperature monitoring data, determining a temperature abnormal region, analyzing the temperature change trend of continuous time points, identifying an overheating region based on the temperature abnormal region and the temperature change trend, marking the spatial coordinates of the overheating region, determining the temperature change rate of the overheating region, and generating temperature evaluation data according to the area occupation ratio of the overheating region and the temperature change rate; Determining a cooling demand intensity value of each cooling area according to the space coordinates and the temperature evaluation data, and adjusting the operation parameters of each cooling area based on the cooling demand intensity value to generate a cooling control instruction; and acquiring outlet temperature data of the PCB at the outlet, determining a temperature deviation value according to the historical cooling effect data and the PCB moving speed when the outlet temperature data exceeds a safety temperature threshold, and correcting the operation parameters of each cooling area according to the temperature deviation value. Further, identifying an overheating zone, marking spatial coordinates of the overheating zone, and determining a rate of temperature change of the overheating zone includes: when the temperature value of the temperature abnormal region exceeds a high temperature threshold value and the slope of the temperature change trend is larger than a rising rate threshold value, judging that the current region is an overheat region; Acquiring boundary point positions of the overheat areas based on a coordinate system of the PCB, and determining vertex coordinates of the minimum circumscribed rectangle as the space coordinates; and determining the temperature change rate according to the temperature time sequence of the overheat area. Further, when generating the temperature evaluation data, the method includes: Determining the area of the ov