Model Reference Adaptive Theory Research Articles

Robust Control of EHCS of Intelligent Commercial Vehicle under Load Change

Electro Hydraulic Coupling Steering (EHCS) system is a new type of intelligent commercial vehicle steering system, having strong nonlinear characteristics. Besides, the change of load would cause the change of control system parameters, making not easy to establish an accurate control model of it. To realize the robustness of EHCS under the change of load, the controller based on the adaptive control method is proposed in this paper. To this end, the cosimulation model of EHCS is first established, where the constructed control model is simplified to a 2‐degree‐of‐freedom model under reasonable simplification and assumption. Then, the steering angle controller is designed based on the model reference adaptive theory. Finally, some simulations are given to show the effectiveness of the proposed control method.

Modified complementary sliding mode control with disturbance compensation for permanent magnet linear synchronous motor servo system

In this study, a modified complementary sliding mode control (MCSMC) method based on a disturbance force observer with mass identification (DFOB-MI) applicable to the permanent magnet linear synchronous motor is proposed to achieve high-performance servo control fields. MCSMC is an improvement on the complementary sliding mode control (CSMC) method, which incorporates an approach angle into the saturation function. MCSMC allows for asymptotic convergence of the position tracking errors and guarantees the global robustness of the system. In addition, compared to hybrid control strategies combining neural networks with CSMC, the MCSMC method has a simpler structure and faster response. However, in practical applications, the mass variation of the mover has a significant impact on system performance. To achieve better dynamic and static characteristics, a disturbance force observer capable of identifying the mass variation based on model reference adaptive identification theory is proposed. DFOB-MI can identify the mass of the mover and provide information on the disturbance caused by the change of the load. Thus, the compensation current is calculated to reduce the disturbance and realise compensation. The more accurate tracking performance and stronger robustness of the proposed control scheme compared to conventional approaches have been confirmed through comparative experimental studies.

Analysis of Magnetic Properties of AlNiCo and Magnetization State Estimation in Variable-Flux PMSMs

Variable-flux permanent-magnet synchronous machines have gained a lot of attention for their ability to expand the speed range and reduce loss over an electric vehicle drive circle by manipulating magnetization state (MS) dynamically. In this paper, a combined-magnet-pole variable-flux machine (CMP-VFM) using both AlNiCo and NdFeB is analyzed. To obtain the variation laws of MS quickly and precisely, a 3-D neural-network hysteresis model of AlNiCo is proposed, and the accuracy and time consumption of the proposed neural-network hysteresis model are evaluated. In order to optimally utilize the speed expansion and loss minimization capability with precise MS control, a flux observer based on model reference adaptive theory is proposed for the closed-loop flux control of CMP-VFM and validated by simulations. The simulation results prove that the accuracy of the proposed adaptive flux observer is almost not affected by parameter disturbance.

Predictive direct power control for three-phase grid-connected converters with online parameter identification

Summary It is well known that predictive direct power control method can be influenced by the presence of modeling errors. Any small variations in model parameters will degrade the performance and stability of the control system. However, this value is difficult to be measured precisely in practical implementation. This paper proposes a predictive direct power control method for three-phase grid-connected converters with online parameter identification technique. Specifically, the proposed method alleviates the parameter mismatch problem by using the online parameter identification technique based on model reference adaptive system estimation theory. The proposed strategy not only identifies the parameter accurately, but also improves dynamic response without any additional sensors. The excellent steady-state and dynamic performance of the proposed method are confirmed through extensive simulations. Copyright © 2016 John Wiley & Sons, Ltd.

Support vector regression and model reference adaptive control for optimum control of nonlinear drying process

In this paper, a support vector regression (SVR)-based system identification and model reference adaptive control (MRAC) strategy for stable nonlinear process input-output form is designed. In order to implement the proposed control structure, SVR-based identification methods are clearly addressed. The control of a moisture process on the paper machine illustrates the proposed design procedure and the properties of the SVR-based model identification-adaptive reference model for the nonlinear system. MRAC is widely used in linear system control areas, and neural networks (NN) are often used to extend MRAC to nonlinear areas. Some drawbacks of NN with MRAC are slow speed in learning, weak generalization ability, and a local minima tendency. To overcome this problem, SVR is used instead of NN. With the support vector regressor, a stable controller-parameter adjustment mechanism is constructed by using the model reference adaptive theory. Simulation results show that the proposed approach could reach desired performance.

Speed Sensorless Control System Based on MRAS

In this paper, a strategy for estimating the induction motor’s rotor speed is proposed. The proposed rotor speed estimation strategy is based on model reference adaptive identification theory. By applying the proposed strategy, the induction motor control system can estimate the induction motor's rotor speed precisely. To improve the rotor speed estimation performance of the system, two methods have been adopt. The speed sensorless control system based on proposed strategy was built with Simulink blocks in Matlab platform. The corresponding simulation results demonstrate that the proposed method can operate stably in the whole range of speed with preferable estimation precision of stator resistance and rotor speed.

Application Research of MRAC in Fault-tolerant Flight Controller

Damage, failure, and other configuration variety of aircraft would make the model parameters changed uncertainly, and lead to unknown deviations of the equilibrium points and unexpected coupling characters. One type of fault-tolerant flight controller which contains model reference adaptive theory is released for dealing with these problems. Design requirement for fault-tolerant flight controller is discussed and one structure of controller is presented. The reconstruction simulation for serious shift of center of gravity which could not detected by FDI system demonstrates this type of controller can complete the reconfiguration task without failure information, and demonstrated the validity of this structure.

Adaptive Current Control for Grid-Connected Converters With LCL Filter

This paper presents a discrete-time adaptive current controller for grid-connected pulse width modulation voltage source converters with LCL filter. The main attribute of the proposed current controller is that, in steady state, the damping of the LCL resonance does not depend on the grid characteristic since the adaptive feedback gains ensure a predefined behavior for the closed-loop current control. An overview of model reference adaptive state feedback theory is presented aiming to give the reader the required background for the adaptive current control design. The digital implementation delay is included in the model, and the stability concerning the variation of the grid parameters is analyzed in detail. Furthermore, current distortions due to the grid background voltage are rejected without using the conventional stationary resonant controllers or the synchronous proportional-plus-integral controllers. Simulation and experimental results are presented to validate the analysis and to demonstrate the good performance of the proposed controller for grid-connected converters subjected to large grid impedance variation and grid voltage disturbances.

Design and Simulation of Speed Sensorless Control System for Induction Motor

In this paper, a method for estimating induction motor’s rotor speed is proposed. The proposed rotor speed estimation method is based on model reference adaptive identification theory. By applying the proposed method, the induction motor control system can estimate the rotor speed of the induction motor precisely. To improve the rotor speed estimation performance of the system, one input filter and one output filter are introduced into the speed sensorless control system. The introduced input filter and output filter enhance the estimation accuracy and improve the reliability and robustness of the system. The speed sensorless control system based on proposed method was built with Simulink blocks in Matlab platform. The simulation results indicate that the proposed method can operate stably in whole range of speed with preferable identification precision of the rotor speed.

Speed Sensorless Vector Control System of Induction Motor

This paper introduces a vector control system for speed sensorless induction motor drive, which we have recently developed. In the introduce vector control system, one induction motor’s rotor speed estimation method based on model reference adaptive identification theory is proposed. The induction motor speed identification system based on the proposed method can estimate the rotor speed of the induction motor. The speed sensorless vector control system based on proposed method in this paper was built with Simulink blocks in Matlab platform. The simulation results indicate that the proposed method could operate stably in whole range of speed with preferable identification precision of rotor speed.

Rotor Speed and Stator Resistance Identification of Direct Torque Control for Induction Motor Based on Mutual MRAS

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control of induction motor. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, The induction motor speed sensorless direct torque control system can obtain high-precision speed identification. Computer simulations and experimental results show that the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

Rotor Speed Adaptive Identification of Direct Torque Control for Induction Motor

Based on the dynamic mathematical model of induction motor, the mutual model reference adaptive system method (MRAS) for rotor speed identification is proposed to implement a speed sensorless direct torque control. The model reference adaptive theory is flexibly used in the rotor speed and the stator resistance online identification. The reference model and adjustable model used in the mutual MRAS scheme are interchangeable. Therefore, the control system can obtain high-precision speed identification. Simulation results show the method can solve the problems of speed control accuracy and system stability under the influence of motor parameter variation. The low speed performance of DTC is also improved.

Improvement of Social Disaster Environment of Developing Countries Arising from Model Reference Adaptive Theory

At present, the world population of developing countries is increasing rapidly and the resident space is approaching a disaster critical section. Therefore, the help from the both sides of the thing and person is indispensable for the scientific analysis of the natural disaster environment and the improvement of the social disaster environment in the developing country by the United Nations and the various help organization. The present study investigated the features of sustainable disaster environment and future prospects for adaptation policies on the four models such as the parallel, series, parallel-series and series-parallel models arising from Model Reference Adaptive Theory. When thinking of adaptation policies by these models, it is important to note that the actual disaster environment is to be become the effective circulation by the disaster environment criteria based on the disaster recognition of real disaster environment and the schematic representation of disaster crisis.

Analysis on Wastepaper Recycling System of Developing Countries Arising from Model Reference Adaptive Theory

The present study investigated the features of wastepaper recycle system for the adaptation policies of developing countries based on Model Reference Adaptive Theory. When we intend to seek the wastepaper recycle system, it is therefore very important to investigate a number of paths that converge the sustainable development environment. Bangkok is facing the problems related to the waste disposal because of the limited capacity of incineration, composting plants, and only few open dumping sites. This study aims especially to inform business leaders, wastepaper suppliers, and pulp and paper manufactures to cooperate and set up an office paper recycling scheme for the manufacturing of new paper products. Manufactures in Thailand often face shortages in imported wastepaper. It would be desirable to increase the domestic wastepaper supply not only for the economic benefits but also for the environmental benefits as well. With the depletion of natural resources occurring throughout Thailand, the reduction of the use of natural resources would be a positive thing for Thailand environment.

Environmental Repercussive Analysis on Industrial Location of Developing Countries Arising from Model Reference Adaptive Theory

The present study investigates the features of sustainable development and environment, and future prospects for the adaptation policies of developing countriesbased on Model Reference Adaptive Theory. When we intend to seek the sustainabledevelopment and environment, it is therefore very important to investigate a number of paths which converge the sustainable development and environment. It is well known that pollution will always accompany industrial manufacturing activities. Therefore it is necessary to investigate the repercussive pollution arising from large-scale industry in allow for the government to plan protection. This research has adopted the method of measuring the repercussive pollution based on Input-Output Model, and measured the repercussive impact arising from the location of manufacturing industries in the Eastern Seaboard Industrial Complex in Thailand. In main results, Central region has the highest level of pollution and the indirect repercussive pollution impacts Bangkok.

Environmental Analysis on Urban Transportation Problem of Developing Countries Arising from Model Reference Adaptive Theory

World trends of urban population growth are already high, but motorization growth trends are much worse. In developing countries motorization is not only high, but also its rate is uncontrollably high, reaching rate over 10% per year. During the traffic jams, general average speed of all the vehicles is kept slow that the emissions of pollutant gases are evidences to be much higher than in a kilometer per person basis. Motorization tends are truly astonishing but alsohere the income-level distribution plays a key role in developing countries. The present study investigates features of sustainable transportation environment and future prospects for the adaptation policies of developing countries based upon Model Reference Adaptive Theory. In the case of La Paz City, Bolivia, the income-level distribution has a great influence on daily life citizens. The number of vehicles that cross each of the network on each peak period for each income level and trip purpose is estimated using GIS. The buses would provide service for the most congested routes and the current vehicles would feed the big buses system. Through this adaptive policy, the congestion would be significant reduced.

Interaction to Development and Environment of Sakhalin and Hokkaido Arising from Model Reference Adaptive Theory

Interaction to Development and Environment of Sakhalin and Hokkaido Arising from Model Reference Adaptive Theory

Application for Industrial Water Pollution in the Philippines through the Model Reference Adaptive Theory

The objective of this paper is to summarize an affective measure for industrial water pollution issues in the Philippines on the Model Reference Adaptive Theory.Nowadays, a developing country such as Asian countries are success in modernization and industrialization. However, there are some seriousness of industrial pollution issues, such as water contamination. We can find some difficulty investment for environmental management in developing countries, because those countries prefer to enjoy there profit.We summarize a current state in water pollution problems in the Philippines as example of the developing countries.They believe such investment for environment is not be able to give any profit. We have to realize some environmental damage will bring a some economic restriction. We have an experience on industrial pollution in 1960's and '70's in Japan. We concur the industrial pollution in not only own measure in industrial sector but also some industrial and environmental policy. From our experience in the industrial pollution issues, legislative functions and some investment are required.The Model Reference Adaptive Theory can provide most useful information from experiences as some models, as well as the theories assist to adapt to the developing countries to solve an industrial pollution issue.We would like to suggest that to summarize that re-use of industrial water is secure not only to minimize a discharge a waster water but also to minimize a pollution control cost. It is true that systematic analysis which combined with policy-guided and investment of industries in Japanese experience on the industrial pollution measures.1) input unit of resources in changing industrial structure and changing of environmental quality2) strengthening on environmental regulation due to their aggravation on environmental quality and investment and some affection on economy3) investment for R&D in industry and their effect4) some incentives for environmental conservation and their effect5) creation of environmental business from aggravation of environmental quality and strengthening on environmental regulationWe also would like to suggest to set those comprehensive programs from Japanese experience on measure on water pollution.1) Comprehensive program for water usage2) Monitoring plan for water quality3) Comprehensive master plan for environmental management