A NEW SELF-TUNING PID CONTROL ALGORITHM BASED ON PROCESS PARMETER IDENTIFICATION

In this paper,the open loop response curve is computed by a computer after the process paramter estimatio The parameters of PI or PID controller are computed by the method of respose curve. Then in order to obtain better control performance, the parameters of PI or PID controller are gradually optimized.This algorithm is with wider application range compared with the other self-tuning PID control algorithms. The computer simulation and real-time control trials shows a good result.     

AN AUTOMATIC VOLTAGE REGULATOR USING IDENTIFIED MODELS

This paper obtains the mathematical model of a single machine infinite bus power system using the idea of parameter identifications. Because the noise is considered in parameter identification process, the model reflects the real system more exactly. On the base of the identified model this paper also presents a discrete automatic voltage regulator by minimum variance control principles. In order to avoid the static error, we combine discrete minimum variance control with continuous integral control and get very satisfactory effects. This proposed control strategy is very easy to realize. The simulation results show that in every case the dynamic qualities of the proposed control strategy are incomparably superior to that of the conventional PI regulator, which means the proposed control strategy has great practical values.     

THE INVESTIGATION AND DEVELOPMENT OF CONTROLLED TEMPERATURE SYSTEM WITH MICROCOMPUTER

This paper introduces a controlled temperature system in which the silicon controlled rectifier is controlled by a TP-801 microcomputer. A common-used PID expression is usually applied to control temperature, but it is necessary to adjust three parameters, making the operation quite inconvenient. This system adopts the measurement of a simplified expanded-critical proportion, only one parameter is necessarily adjusted. In addition, the method of digital triggering is applied so that the D/A transfer and silicon adjuster are omitted, thus decreasing the cost and increasing the reliability of operation. This system has higher precision of control and better degree of linearity of temperature increment or decrement.     

Research to Algorithms of the Regulators in Digital Control System

The R S T algorithms structures of usual digital regulator are researched and the results are given. It has solved the problem of relationship between the digital regulator and dynamical characterization of system. It is a direct and quick algorithm of the digital regulator based on the characteristic equation of control system. This algorithm is especially suitable for numerical simulation of control system which contains digital regulator.[WT5HZ]     

PID Control for Multivariable System Based on Ameliorative RBF Neural Networks

Aiming at systems which are of characteristics of multi-input and multi-output, nonlinearity and time-variation in the industrial control fields, this paper presents a intelligent PID control method based on ameliorative RBF neural networks, which constructs RBF neural networks identifier on-line and identifies a controlled object on-line by means of adopting the nearest neighbor-clustering algorithm, and adjusts parameters of PID controller on-line and realizes decoupiing control of multivariable, nonlinear and time-variation system. The simulation result indicates that the controller can get parameters which are optimal under some control law, it makes the decoupled system, compared to the PID control method based on the conventional RBF neural networks, has perfect dynamic and static performances, possesses the advantages of high precision, quick response speed and is of great adaptability and robustness.     

Improvement and simulation on direct torque control system of permanent magnet synchronous motor

To solve the problems of large flux, torque ripple and inconstant inverter switching frequency in conventional direct torque control (DTC), a space vector modulation (SVM) technique is introduced to the conventional PMSM-DTC system and analyzed thoroughly based on the mathematical model. This novel control method which enjoys the advantages of VC and DTC has only one easy adjustable PI regulator and is easy to realize. The simulation verifies that this control system is capable of effectively improving the steady state performance and keeping the excellent dynamic performance of the PMSM-DTC system simultaneously and remain the switching frequency constant.     

Implementation of PID Algorithm Based on MATLAB in Cascade Control System

This paper presents the character of cascade control system and the design of the main loop and subloop. A cascade PID control system based on MATLAB is designed, which is controlled by MATLAB control program based on incremental PID control algorithm and PID parameter tuning method based on computer control. The results show that the control system has good performance.     

Vehicle stability control system design using optimal allocation of yaw moment

In order to improve vehicle handling stability,a control system using optimal allocation of yaw moment was designed.The first layer is a linear quadratic regulator (LQR) controller,which optimizes a desired yaw moment to work on the vehicle and calculates reference wheel slip for the target wheel.The second layer of the control system is a PID controller which can track the reference wheel slip rate,and then apply braking torque on the target wheel to make the vehicle stable.Simulations are carried out by using an 8-dof nonlinear vehicle model under different conditions.The simulation results indicate that the designed control system can effectively improve vehicle handling stability.     

基于人工智能的温室环境控制算法

温室环境控制系统的最大特点是控制对象的精确数学模型很难建立。文章将常规PID控制算法与现代控制理论相结合,对常规PID算法进行改进,得到新型MPT控制算法,并加入模糊控制算法规则,在误差大时,运用模糊算法进行调节,以彻底消除PID饱和积分现象,当误差较小时,采用改进后的PID算法控制输出。同时加入了自适应调节规则和自整定专家系统,建立了基于人工智能的温室环境控制算法。将此算法应用于温室环境控制。系统具有无超调和控制精度高等特点。     

Temperature Control of High Temperature Melt Viscosity Test Instrument

The construction and function of high temperature melt viscosity test instrument are introduced in this paper. And the character of temperature control system is given. In order to improve dynamic and static performance of the temperature control system, a new method is proposed which combines threshold control with adaptive fuzzy PID control. While the current temperature of the heating furnace is much lower than the given temperature, threshold control works in order to protect system and improve dynamic performance. When the current temperature is close to the given value, adaptive fuzzy PID control works to improve static performance. At last, simulation and experiment results validate the proposed control method.     

Control Strategy of DO Parameter Based on Human Simulated Intelligence in the Wastewater Treatment Process

The treatment of wastewater is a complicated biological and chemical process, which can not be described precisely with a mathematical model. It is almost impossible to get a satisfactory control result when a traditional PID control method is adopted, for the parameters of the activated-sludge process are uncertain. The paper takes DO parameter controlling as an example, and proposes a human-simulated intelligent control strategy to reduce the fluctuation problem of DO parameter. Both the control rules and the structure of control system are presented. The simulation experiments shows that the control effect of activated-sludge process by HSIC is much better than PID control.     

不同植物生长调节物质对玉米根系衰老及产量的影响

为探讨不同植物生长调节物质对玉米根系衰老及产量的调控效应。采取盆栽试验和大田试验,以玉米品种郑单958为材料,研究了7种植物生长调节物质拌种处理对玉米根系生长、根系活力、根系抗氧化及产量的影响。结果表明:7种植物生长调节物质拌种处理后根系发达,根系数量增多,根量增大,根系活力和后期根系中抗氧化酶的活性增强,延缓根系衰老,且复合处理的效应明显大于单一处理。在各处理中,E调控效应最为明显,玉米产量较CK提高9.93%。表明不同植物生长调节物质对玉米根系衰老及产量具有明显的调控作用,在玉米生产应用复合生长调节物质E是一项可行的技术。     

双氧威的特点及其在储粮害虫防治中的效用

文章根据大量的参考文献对昆虫生长调节剂双氧威的特性，防治储粮害虫的效用进行了综述。指出双氧威是迄今仅见的具有广谱杀虫作物的保幼激光型化合物，可以有效防治敏感和抗性品害虫，无残毒和环境污染问题，有广阔的发展前景。     

Fuzzy PID Power Adjustment of Computer Monitor and Control System for Hydropower Station

The computer monitor and control system for hydropower station is always a structure system of laminate distribution and open style. The system can adjudge active power and inactive power of water turbine according to the requirement. The operators in active-control level give the value of active power and inactive power for water turbine by computer workstation. PLC of LCU run the power control procedure by net communication in order to realize power adjust. The power adjust of water turbine mainly by speed control system and magnetization system. The 2-D Fuzzy PID Control Model is proposed in order to carry out power adjust of water turbine . In this new method the parameter of PID can self-neaten on line according to power deviation and power deviation rate. By means of this procedure the machine unit can obtain given power value rapidly, exactly and stably. It can make the power adjust of monitor and control system obtain good control characteristic and robust, and it is benefit to extend the work life of machine unit.     

新型植物生长调节剂对烟草花叶病的控制作用

【研究目的】为开发和创制新的烟草病毒病控制药剂提供依据，从而指导烤烟生产中花叶病的防治问题；【方法】试验设芸苔素内酯400倍，8 %宁南霉素水剂800倍与清水对照(cK)3个处理，3次重复，随机区组设计；【结果】在重庆市黔江烟区，用植物生长调节剂——芸苔素内酯和宁南霉素两种生物药剂进行了防治烟草花叶病毒病侵染烟草的田间试验，结果表明：两种药剂对烟草花叶病均具有比较好的控制效果，相对防效均在70%左右，且对烟草生长具有一定的促进作用。【结论】芸苔素内酯不但能发挥其生长调节剂的功能——促进烟草生长，而且也是防治烟草花叶病的较为理想的药剂。     

Development of Software Reuse Technology in Industrial Control Software Area

This paper briefly introduces the contents and characteristics of the software reuse technology and industrial control software. The development of the software reuse technology in industrial control software area is discussed emphatically. Then the article brings forward a kind of thought that establishes standard element class library and develops the application program frame adapts to industrial control area. Namely, they are the establishment of the reuse of standard element class library based on the level of class library, the design of the reuse of the program frame based on the level of design, the amelioration of the reuse of the designing method based on the level of analysis. This thought improves on design method of industrial control software and is applied in the real-time monitoring system for the high-press water pump station.     

水果中8种外源性植物生长调节剂的液相色谱-串联质谱测定

摘要：【研究目的】建立水果中8种外源性植物生长调节剂乙烯利、丁酰肼、抑芽丹、赤霉素、玉米素、氯吡尿、矮壮素、α－萘乙酸的液相色谱-串联质谱测定方法。【方法】样品制备后,采用乙腈提取,经过certify Ⅱ固相萃取柱净化处理后,采用LC-MS/MS由电喷雾(ESI),多反应监测（MRM）,负离子模式检测（其中矮壮素是正离子模式）,外标法定量。【结果】在2.0～100.0?g/L范围内,8种植物生长调节剂的回收率在70.0～101.0%,相对标准偏差（RSD）均在10%以内。【结论】所建立的方法简便快捷,可满足检验检疫实际需求。     

Nonlinearity of Electronic Throttle and Its Control

This paper introduces the development of the electronic throttle control system (ETCS) , the structure and the principle of the system are also involved. After analyzing the nonlinearity problem existing in the mechanical structure of the system, a mathematical model of the ETCS is built up. Then three controllers (PID controller, Fuzzy controller, sliding mode controller) were designed and simulated in the matlab simulink. The result indicates that the PID controller has an overshoot,but the Fuzzy controller and the sliding mode controller can settle the nonlinearity problem better.     

Simulation Research of Control Parameters in Induction Motor Vector Control System

In order to obtain the effect rules of control parameters of speed regulator on performance indexes of induction vector-controlled system and the setting rules of control parameters of speed regulator,according to rotor flux oriented control principle,a vector control model of induction motor is established and simulated with the software of Matlab/Simulink.This vector control system is proved that it possesses good static and dynamic performance.This paper analyzes the effect of control parameters' variations of speed regulator on performance indexes and gives simulation results.     

基于PID算法对热风炉热风温度控制及仿真分析

在农作物金银花干燥期间,为了满足干燥热风的温度和风速的稳定性要求,针对热风炉出风口热风温度与设定的温度值滞后和稳定性差等问题,设计了一套以单片机STM32作为核心处理器和模糊自适PID算法作为参数控制器的控制系统,实现模糊自适PID算法对参数进行调整。利用Matlab语言建立模型,对整套控制系统进行仿真分析。结果表明:出风口热风温度的稳定性能达到95%以上,该研究方法提高控制系统的性能,有利于农作物干燥的质量和效率。