BP-PID intelligent control system for constant temperature drying oven

Abstract

The present application relates to a kind of BP-PID intelligent control system for constant temperature drying oven, belong to industrial oven precision temperature control technical field.The system is by using BP neural network algorithm, the parameter of traditional PID controller is dynamically set online, combined with the high-precision temperature and humidity sensor of multiple point layout in the box, constructs adaptive temperature control loop with self-learning ability.BP neural network is fed forward according to the deviation of system real-time operating state and set value, real-time adjustment PID parameter to match the dynamic characteristics of controlled object.The system can significantly improve the dynamic response speed and steady control precision of constant temperature drying oven under the working condition such as temperature rise, anti-interference, effectively overcome the shortcomings of large overshoot and poor adaptability of traditional PID control, provide highly stable and uniform thermal environment for the drying process of temperature sensitive material, significantly improve product quality and drying efficiency.

Description

Technical Field

[0001] This invention relates to a sensing structure for monitoring multi-layer environmental parameters inside a tobacco constant temperature drying oven, belonging to the field of tobacco drying technology. Background Technology

[0002] The tobacco drying process has a decisive impact on the quality, aroma, color, and combustion performance of tobacco. Traditional tobacco drying boxes mainly rely on manual experience to control temperature, humidity, and airflow, but this approach has several problems in practical applications. First, existing drying boxes often use single-layer or localized temperature and humidity data collection, which cannot comprehensively reflect the actual environmental conditions of different layers and areas. Second, wind speed, a key parameter affecting moisture evaporation and the uniformity of tobacco drying, is often overlooked; uneven airflow can lead to uneven tobacco drying. Furthermore, the weight change of tobacco during the drying process directly reflects the dehydration progress and quality changes, but currently, there is a lack of real-time and systematic tobacco weight monitoring methods; it usually relies on manual sampling, which cannot efficiently and accurately control the drying process.

[0003] Furthermore, existing sensors are often deployed independently, resulting in a lack of time synchronization in the collected data, making it difficult to achieve multi-parameter collaborative modeling and control. Particularly in multi-layer tobacco drying chambers, existing sensor structures struggle to effectively penetrate the tobacco layers, leading to monitoring blind spots. Therefore, a novel multi-layer monitoring system is needed to comprehensively and in real-time collect various environmental parameters during the tobacco drying process, and to ensure data consistency through a time synchronization mechanism, thereby achieving more efficient and precise drying control. Summary of the Invention

[0004] This invention relates to a BP-PID intelligent control system for a constant temperature drying oven.

[0005] The specific technical solution adopted in this invention is as follows:

[0006] A multi-layer temperature, humidity, wind speed, and tension sensor array structure capable of penetrating tobacco leaf layers includes multiple vertical monitoring rods within the main structure of the drying chamber. Each rod extends from the bottom to the top of the drying chamber, with temperature and humidity sensors evenly distributed across three layers at different heights, constructing a three-dimensional cross-monitoring network covering the entire space. All sensors are connected to a centralized data acquisition module via an RS485 bus, enabling multi-parameter collaborative sensing and time-series alignment. The system employs a BP-PID intelligent control algorithm for data processing and analysis. Through precise calculation and automatic adjustment of the heating and fan systems within the drying chamber, it ensures balanced and precise temperature and humidity control across each layer of tobacco during the drying process, thereby guaranteeing high-quality drying and standardized production.

[0007] The advantages and positive effects of this invention are as follows:

[0008] (1) Precise temperature and humidity acquisition: This invention ensures that real-time temperature and humidity data can be accurately acquired at three different levels inside the drying oven by setting multiple temperature and humidity sensors at different heights. By deploying vertical sensors, the problem of temperature and humidity monitoring of the tobacco layer inside the sealed box is overcome, effectively eliminating the blind spots of environmental monitoring in traditional structures and ensuring uniform temperature and humidity distribution of tobacco throughout the drying process.

[0009] (2) Dynamic adjustment of fan control: By combining real-time temperature and humidity data, the present invention can effectively promote air circulation and humidity control, optimize air flow in the box, ensure the consistency and uniformity of the drying process of tobacco in each layer, thereby improving drying efficiency and reducing energy consumption.

[0010] (3) Unified timestamp and data synchronization: The sensor nodes of the present invention have a unified timestamp mechanism to ensure the consistency and synchronization of multi-point temperature and humidity data acquisition. This mechanism forms a high-frequency, highly consistent multi-dimensional data stream, which provides an important data foundation for the subsequent establishment of an accurate drying process control model and improves the automation and intelligence level of the drying process.

[0011] (4) Modular Design and Environmental Adaptability: The structural design of this invention adopts a modular approach, which provides flexibility and adaptability. The system can be quickly deployed and modified according to different oven structures and sizes, and can adapt to the harsh conditions of industrial environments such as high temperature and high humidity, ensuring long-term stable operation. In addition, the system has good weather resistance and anti-interference capabilities, and can cope with complex working environments. Attached Figure Description

[0012] When considered in conjunction with the accompanying drawings, the invention will be better understood and its accompanying advantages readily apparent from the following detailed description. However, the accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are intended to explain the invention and do not constitute an undue limitation thereof.

[0013] Figure 1 This is a structural diagram of the oven of the present invention.

[0014] Figure 2 This is a layout diagram of the longitudinal sensor of the oven of the present invention.

[0015] Figure 3 This is a picture of the heating rod of the present invention.

[0016] Figure 4 This is a layout diagram of the oven temperature and humidity sensor of the present invention.

[0017] Figure 5 This is a photograph of the actual oven of the present invention.

[0018] Figure 6 This is a data acquisition diagram for the present invention.

[0019] Figure 7 This is a structural diagram of the BP-PID feedback control algorithm of the present invention.

[0020] In the diagram: 1. Industrial control panel 2. Temperature controller 3. Platinum resistance thermometer 4. Heating rod 5. Airflow circulation fan Detailed Implementation

[0021] The present invention will be further illustrated below with reference to the accompanying drawings and embodiments. However, these embodiments are merely illustrative, and the scope of protection of the present invention is not limited to these embodiments.

[0022] Combination Figure 1 , Figure 2 , Figure 4 The present invention provides a detailed description of a multi-layer environmental parameter monitoring system for a tobacco drying oven: a sensing structure for monitoring multi-layer environmental parameters within a tobacco drying oven, comprising multiple vertical sensors arranged inside the drying oven, each sensor installed at a different height level to ensure accurate collection of temperature and humidity data for each layer of tobacco. Specifically, as... Figure 2 As shown, temperature and humidity sensors are evenly distributed at different heights inside the drying chamber, forming a longitudinal multi-point environmental acquisition path, ensuring that the environmental status of each layer of tobacco can be monitored in real time.

[0023] like Figure 4 As shown, the placement of all temperature and humidity sensors is precisely calculated to ensure uniform temperature and humidity distribution within the chamber. The location of each sensor's data collection point is flexibly adjusted according to the needs of different levels. The system can automatically adjust the fan based on the temperature and humidity data from each level, ensuring that the tobacco on each level is dried evenly.

[0024] like Figure 5 The diagram shows the external structure of the drying oven of this invention. The oven adopts a sealed chamber design, with multiple temperature controllers distributed on the exterior to ensure precise monitoring of the environmental conditions of each layer of tobacco during the drying process. By collecting environmental data in real time through temperature and humidity sensors, the system can automatically adjust the temperature and humidity inside the chamber and optimize airflow through the control system to ensure uniform heating and drying of each layer of tobacco.

[0025] All temperature and humidity sensor data are connected to a centralized data acquisition module via an RS485 bus, such as... Figure 6 As shown. The data acquisition module synchronizes the data from each layer of sensors via a host computer, with a acquisition cycle of 1 minute. It supports local caching and uploading to a local database. The host computer software allows real-time viewing of the time-series curves and data evaluation of temperature and humidity at each layer, enabling remote monitoring and adjustment of the drying process. Figure 7As shown, this invention employs a BP-PID feedback control algorithm, using a BP neural network to tune the three key parameters (Kp, Ki, Kd) of the PID online, enabling the system to dynamically adjust the control strategy according to multi-level environmental changes, thereby improving the accuracy and response speed of temperature and humidity control.

[0026] During implementation, this solution was applied to a standard drying oven in Henan Province. Through the deployment of this invention, high-density, multi-level, and full-coverage data collection of temperature and humidity was achieved. The system significantly improved the spatial resolution and temporal accuracy of environmental factors inside the drying oven, greatly enhancing the real-time monitoring capability of the drying process. Through integration with an intelligent control system, the system can achieve more precise drying adjustments, ensuring optimal results in the tobacco drying process.

[0027] The above examples are only for the purpose of helping to understand the core idea of ​​the present invention; at the same time, those skilled in the art will know that there will be changes in the specific implementation methods and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A BP-PID intelligent control system for a constant temperature drying oven, characterized in that: It includes a high-precision temperature sensor, a high-precision humidity sensor, a control unit, and an execution unit. The temperature and humidity sensors are used to monitor real-time temperature and humidity data inside the drying chamber. The control unit combines a BP neural network with a PID control algorithm to adjust the operation of the execution unit based on real-time sensor data, accurately controlling the temperature, humidity, and airflow state inside the drying chamber to maintain a constant temperature and humidity environment.

2. The control system according to claim 1, characterized in that: The control unit adopts a composite control algorithm that combines BP neural network and PID control. By adjusting the PID parameters in real time, the system has strong adaptability and robustness to temperature and humidity fluctuations.

3. The control system according to claim 1, characterized in that: The execution unit includes a heater, a fan, etc., which are used to adjust the temperature and humidity inside the drying chamber to meet the set requirements.

4. The control system according to claims 1 to 3, characterized in that: The system connects to a remote monitoring terminal via the Modbus protocol, supports local and cloud data storage and real-time monitoring, and provides data backup and remote operation functions.

5. The control system according to any one of claims 1 to 4, characterized in that: The system features a modular design, supporting adjustable layout schemes for drying ovens of different sizes, and allowing for flexible configuration of control unit and sensor layouts according to different application requirements.

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