| The 14th Five-Year Plan of traditional Chinese medicine puts forward higher requirements in ensuring drug safety,ensuring drug quality stability and promoting the modernization of traditional Chinese medicine industry.Traditional Chinese medicine extraction is one of the key links to ensure the quality of traditional Chinese medicine in the production of traditional Chinese medicine.However,the existing extraction equipment of traditional Chinese medicine has fluctuations in the quality of liquid medicine due to fixed process parameters and uncontrollable temperature and pressure.In addition,when the near-infrared on-line detection is applied to the extraction process of traditional Chinese medicine,the on-line detection of liquid medicine quality is inaccurate due to the complex detection environment,large temperature fluctuation,bubble interference and other factors.This paper solves the problem of poor consistency of liquid quality in the extraction process of traditional Chinese medicine by developing an accurate near-infrared online detection device and establishing an online control model with accurately adjustable temperature and pressure.It has important theoretical significance and application value to ensure the stable,uniform,safe and controllable quality of traditional Chinese medicine.Aiming at the problems of inaccurate,no real-time and unstable detection caused by low constant temperature accuracy,pipeline liquid medicine residue,bubble in circulation pool and single channel detection in the existing near-infrared online detection,a near-infrared online detection device for liquid composition is designed to realize the functions of liquid constant temperature control,circulating flow,static defoaming and multi-channel detection.Aiming at the problem that the composition of liquid medicine is easy to fluctuate due to the low temperature and pressure control accuracy of the extraction equipment,the data acquisition and drive control part of the extraction equipment are improved.Using the "dual controller+upper computer" mode,the double-layer modular control system of near-infrared on-line detection device and extraction equipment is constructed.The hardware selection and circuit design of the control system are carried out according to the performance requirements.Based on the practical application requirements of traditional Chinese medicine extraction,the control algorithm of temperature and pressure is analyzed.Aiming at the problem of low control accuracy of temperature and pressure of traditional Chinese medicine extraction equipment,the pre-feedback compensation decoupling method is used to decouple the parameters of the extraction equipment model.At the same time,the particle swarm optimization algorithm with improved dynamic inertia weight is used to optimize the parameter factors of temperature and pressure fuzzy controller.The PSO optimized fuzzy PID online control model of process parameters of traditional Chinese medicine extraction equipment are constructed.Matlab-Simulink is used to determine the optimal quantization factor and scale factor of temperature and pressure fuzzy controller,and its simulation test is carried out.The results show that the overshoot of liquid medicine temperature and tank pressure curve of extraction equipment is reduced by 90.09%and 89.47%respectively compared with the traditional PID algorithm,the steady-state error is reduced by 1.25℃ and 0.13kPa,the response time is shortened by 12.50%and 60.00%respectively,the adjustment time is shortened by 86.36%and 80.00%respectively,and the temperature deviation and pressure deviation are reduced by 11.05℃ and 1.7kpa respectively,which can solve the problem of curve overshoot and oscillation caused by the fixed parameters of PID control algorithm and ensure the effective,uniform and stable quality of traditional Chinese medicine.Based on the modified TN-100 micro extraction equipment,combined with the nearinfrared online detection device and the online control model of temperature and pressure,the display and monitoring interface of process parameters in the extraction process of traditional Chinese medicine is developed and the test platform of the online control system of process parameters of traditional Chinese medicine extraction equipment is built.The online control test of the liquid temperature and pressure in the tank of the extraction equipment is carried out.The results show that the liquid temperature of the extraction equipment exceeds the overshoot of the traditional PID algorithm the steady-state error and response time were reduced by 66.22%,78.35%and 4.62%on average.Compared with the traditional PID algorithm,the steady-state error and response time of the pressure in the tank are reduced by 0.4875kpa and 0.655min on average.Online control model can reduce the time of reaching the peak value of the liquid components in the extraction process,reduce the fluctuation range of the liquid quality and reduce the energy consumption of the extraction equipment,which can realize the effectiveness of stabilizing the content of the liquid components in the extraction process of Chinese medicine. |
