A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As t...A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As the conventional PID controller is difficult to make the operation temperatures steady, a fuzzy self-tuning PID control algorithm is proposed. The application shows that the algorithm is effective, the operation temperatures of both stages can be controlled steadily, and the operation flexibility and adaptability of the hydrogen recovery unit are enhanced with safety. This study lays a foundation to optimize the control of the membrane separation process and thus ensure the membrane performance.展开更多
Enzyme activity is easily influenced by temperature,resulting in accuracy decline of enzymatic detection of pesticide residues.In this study,a controller which controls the internal temperature of the pesticide residu...Enzyme activity is easily influenced by temperature,resulting in accuracy decline of enzymatic detection of pesticide residues.In this study,a controller which controls the internal temperature of the pesticide residues detector was simulated and analyzed.The mathematical model of temperature control was established by the application of the heat transfer theory.Against models with characteristics of large inertia and large hysteresis,a Smith fuzzy PID controller was proposed by combining the Smith predictor with the fuzzy PID controller.The PID controller,the fuzzy PID controller,and the Smith fuzzy PID controller were simulated in MATLAB,respectively in the same step signal given with amplitude of 1.The performance indexes(percent overshoot,settling time,and steady-state error)of various controllers were presented as follows:the PID controller(19%,250 s,0.0001),the fuzzy PID controller(11%,450 s,0.0001),and the Smith fuzzy PID controller(0%,140 s,0).From 1180 s to 1230 s,an interference signal with amplitude of 5 was added to test interference immunity.The PID controller and the fuzzy PID controller had greater fluctuations,but the Smith fuzzy PID controller had no fluctuations.The recovery time of each controller was described below:the PID controller(200 s),the fuzzy PID controller(300 s),and the Smith fuzzy PID controller(120 s).Robustness of the controller was tested by adjusting the time constant and the delay time.The performance indexes of the controllers were shown as follows:the PID controller(38%,450 s,0.0001),the fuzzy PID controller(23%,880 s,0.00025),and the Smith fuzzy PID controller(1%,150 s,0).The results of simulation showed that the performance indexes of the Smith fuzzy PID controller were better than that of the other controllers.Besides,the robustness and interference immunity are stronger than other controllers as well.The Smith fuzzy PID controller can accurately control the internal temperature of the pesticide residues detector to provide the best temperature for enzymatic detection.展开更多
为解决绣片储存在高温、高湿环境中出现的绣线变色、绣布破损问题,设计了一个绣片柜模糊PID(Proportional Integral Derivative)温湿度控制系统。采用单片机STM32、风扇等元件共同构建硬件控制系统。通过将模糊PID控制温湿度值作为输入...为解决绣片储存在高温、高湿环境中出现的绣线变色、绣布破损问题,设计了一个绣片柜模糊PID(Proportional Integral Derivative)温湿度控制系统。采用单片机STM32、风扇等元件共同构建硬件控制系统。通过将模糊PID控制温湿度值作为输入变量,脉冲宽度调制(PWM)红外管和风扇转速作为输出变量,实现对存储环境中温湿度的控制;使用矩阵实验室软件Matlab对模糊PID控制进行仿真分析。结果表明,与传统PID控制相比,加入模糊控制后,对温湿度的超调量分别由18.75%和15.34%降低至2.51%和2.46%,并且系统不易受外界干扰,能够快速稳定运行。以上结果说明模糊PID控制满足绣片储存的温湿度环境要求。展开更多
Heating, ventilation, and air conditioning (HVAC) system is significant to the energy efficiency in buildings. In this paper, temperature control of HVAC system is studied in winter operation season. The physical mode...Heating, ventilation, and air conditioning (HVAC) system is significant to the energy efficiency in buildings. In this paper, temperature control of HVAC system is studied in winter operation season. The physical model of the zone, the fan, the heating coil and sensor are built. HVAC is a non-linear, strong disturbance and coupling system. Linear active-rejection-disturbance-control is an appreciate control algorithm which can adapt to less information, strong-disturbance influence, and has relative-fixed structure and simple tuning process of the controller parameters. Active-rejection-disturbance-control of the HVAC system is proposed. Simulation in Matlab/Simulink was done. Simulation results show that linear active-rejection-disturbance-control was prior to PID and integral-fuzzy controllers in rising time, overshoot and response time of step disturbance. The study can provide fundamental basis for the control of the air-condition system with strong-disturbance and high-precision needed.展开更多
文摘A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As the conventional PID controller is difficult to make the operation temperatures steady, a fuzzy self-tuning PID control algorithm is proposed. The application shows that the algorithm is effective, the operation temperatures of both stages can be controlled steadily, and the operation flexibility and adaptability of the hydrogen recovery unit are enhanced with safety. This study lays a foundation to optimize the control of the membrane separation process and thus ensure the membrane performance.
基金supported by the National Natural Science Fund Project(31471413)Project A funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)+2 种基金Natural Science Fund Project of Jiangsu Province(BK20141165)China Postdoctoral Science Foundation funded project(2014M561594)Jiangsu Planned Projects for Postdoctoral Research Funds(1401175C).
文摘Enzyme activity is easily influenced by temperature,resulting in accuracy decline of enzymatic detection of pesticide residues.In this study,a controller which controls the internal temperature of the pesticide residues detector was simulated and analyzed.The mathematical model of temperature control was established by the application of the heat transfer theory.Against models with characteristics of large inertia and large hysteresis,a Smith fuzzy PID controller was proposed by combining the Smith predictor with the fuzzy PID controller.The PID controller,the fuzzy PID controller,and the Smith fuzzy PID controller were simulated in MATLAB,respectively in the same step signal given with amplitude of 1.The performance indexes(percent overshoot,settling time,and steady-state error)of various controllers were presented as follows:the PID controller(19%,250 s,0.0001),the fuzzy PID controller(11%,450 s,0.0001),and the Smith fuzzy PID controller(0%,140 s,0).From 1180 s to 1230 s,an interference signal with amplitude of 5 was added to test interference immunity.The PID controller and the fuzzy PID controller had greater fluctuations,but the Smith fuzzy PID controller had no fluctuations.The recovery time of each controller was described below:the PID controller(200 s),the fuzzy PID controller(300 s),and the Smith fuzzy PID controller(120 s).Robustness of the controller was tested by adjusting the time constant and the delay time.The performance indexes of the controllers were shown as follows:the PID controller(38%,450 s,0.0001),the fuzzy PID controller(23%,880 s,0.00025),and the Smith fuzzy PID controller(1%,150 s,0).The results of simulation showed that the performance indexes of the Smith fuzzy PID controller were better than that of the other controllers.Besides,the robustness and interference immunity are stronger than other controllers as well.The Smith fuzzy PID controller can accurately control the internal temperature of the pesticide residues detector to provide the best temperature for enzymatic detection.
文摘为解决绣片储存在高温、高湿环境中出现的绣线变色、绣布破损问题,设计了一个绣片柜模糊PID(Proportional Integral Derivative)温湿度控制系统。采用单片机STM32、风扇等元件共同构建硬件控制系统。通过将模糊PID控制温湿度值作为输入变量,脉冲宽度调制(PWM)红外管和风扇转速作为输出变量,实现对存储环境中温湿度的控制;使用矩阵实验室软件Matlab对模糊PID控制进行仿真分析。结果表明,与传统PID控制相比,加入模糊控制后,对温湿度的超调量分别由18.75%和15.34%降低至2.51%和2.46%,并且系统不易受外界干扰,能够快速稳定运行。以上结果说明模糊PID控制满足绣片储存的温湿度环境要求。
文摘Heating, ventilation, and air conditioning (HVAC) system is significant to the energy efficiency in buildings. In this paper, temperature control of HVAC system is studied in winter operation season. The physical model of the zone, the fan, the heating coil and sensor are built. HVAC is a non-linear, strong disturbance and coupling system. Linear active-rejection-disturbance-control is an appreciate control algorithm which can adapt to less information, strong-disturbance influence, and has relative-fixed structure and simple tuning process of the controller parameters. Active-rejection-disturbance-control of the HVAC system is proposed. Simulation in Matlab/Simulink was done. Simulation results show that linear active-rejection-disturbance-control was prior to PID and integral-fuzzy controllers in rising time, overshoot and response time of step disturbance. The study can provide fundamental basis for the control of the air-condition system with strong-disturbance and high-precision needed.
