# Fuzzy-PID-Based Atmosphere Packaging Gas Distribution System for Fresh Food
###### Abstract  
The regulation process of gas distribution systems for atmosphere packaging has the characteristics of being nonlinear time varying and having hysteric delay. When the conventional proportional-integral-derivative (PID) control algorithm is applied to this kind of system, it is difficult to set the parameters as the process is time consuming and has poor reliability. For these reasons, this paper designs a gas distribution system for fresh food atmosphere packaging based on a fuzzy PID controller. The step response method is used to construct the system's mathematical model under the given conditions and to optimize the gas distribution control flow. A simulation experimental platform to compare between the fuzzy PID controller and a conventional PID controller is designed, and the effectiveness of the fuzzy PID control strategy is verified, which proves that it can improve the performance of the monitoring system. The system can realize the remote monitoring of the gas distribution processes through the use of a mobile phone communication network. The data transmission is reliable, the operation is convenient, and, at the same time, the overall efficiency is improved. The results of the system simulation and the gas distribution for atmosphere packaging show that the fuzzy PID algorithm has a faster gas distribution speed and good environmental adaptability as the controller of the gas distribution system. The results show that the stability time of the fuzzy PID controller is about 38 s, while the stability time of the conventional PID controller is about 85 s. The concentration error of fresh gases is \(\pm\)0.25% floating, the accuracy is increased by 12 times, and the gas distribution speed is increased by about 50% when the system is stable. atmosphere packaging; gas distribution system; remote monitoring; fuzzy PID controller +
Footnote †: journal:  
0000-0002-4000-0000-0000-0000-0000-0000-0000-0000-0000  
from various factors, which could negatively impact the system's stability, resulting in an inability to reach the desired accuracy in mixing gases. Therefore, a reliable control algorithm is necessary. (3) The adjustment of each gas using a control algorithm during the gas distribution process could further degrade the system's stability, and this presents a significant problem in decoupling mutually affected gases. (4) Conventional proportional-integral-derivative (PID) control algorithms are insufficient for nonlinear, time-varying, and hysteresis-delay systems, as they are time consuming, unreliable, and inefficient in setting the parameters [11; 12; 13; 14; 15; 16; 17; 18; 19; 20; 21]. To address these issues, it is essential to design more intelligent PID control algorithms for use in the actual control process. At present, various intelligent PID algorithms are available for use, including expert PID control algorithms, fuzzy PID control algorithms, and neural network PID control algorithms. These algorithms are highly adaptable to time-varying, nonlinear, and hysteresis-delay systems [22; 23; 24; 25]. Expert PID control algorithms have been applied to control simulation systems by modifying the control rules manually [26; 27; 28]. Neural network PID control algorithms have the advantages of fast adjustment and high accuracy, but most of the research is still in the simulation stage due to the complexity of these algorithms [29; 30; 31]. The fuzzy PID control technology has been found to be particularly well-suited for the system requirements of modified atmosphere preservation and automatic gas distribution in similar aquatic products. It not only improves the accuracy and rapid adjustment of such system, but its algorithm also has a high logic. At the same time, it could be embedded in a controller by looking up tables to achieve the development and implementation of the system [24; 25; 32]. For example, [PERSON] et al.