基于VerilogHDL的IP核参数化设计

指出了IP核参数化设计的重要性,分析了IP核的参数类型及相互关系.在分析基于VerilogHDL的IP核参数化设计方法及所面临困难的基础上,提出了一种附加的编译预处理方法并设计了相应的工具软件ECP.IP核由VerilogHDL和ECP扩展的语句混合编程,经ECP处理后生成VerilogHDL源文件.应用该方法后,提高了Ver-ilogHDL在描述功能、性能、结构及优化策略等参数化的复杂模型时所需要的灵活性,增强了VerilogHDL的建模能力.作为一个IP核参数化设计的实例,介绍了C*Core系统中断控制IP的参数化设计过程,给出了FPGA验证的结果.     

Posicast-based digital control of the buck converter

The analysis, design, and microcontroller-based implementation of a digital controller using a Posicast element are presented for the buck converter. Posicast is a feedforward compensator that eliminates overshoot in system response, but the traditional approach is sensitive to variations in natural frequency. The new method described here reduces the undesirable sensitivity by using Posicast within a feedback loop. Compared to classical proportional-integral-derivative (PID) control, the new control results in lower noise in the control signal because the controller has a lower gain at high frequency. Furthermore, the authors' experiments indicate that the new controller is less sensitive to the inherent time delay associated with a digital controller for a dc-dc converter. The authors present a straightforward method to design controller parameters from the small-signal averaged model of the converter dynamics. Experimental results for a PID-controlled converter and Posicast-type controller are also compared.     

永磁同步电机优化控制

为了推进永磁同步电机在实际工程领域的应用,通过Matlab软件搭建了基于滑模变结构的永磁同步电机控制模型.为了使控制效果更加理想,提出了一种优化的指数滑模速度控制器,并针对这种连续的速度控制器在控制系统中进行了仿真.仿真结果表明,控制效果得到了很大改善.     

MPC-based yaw stability control in in-wheel-motored EV via active front steering and motor torque distribution

This paper focuses on yaw stability control of in-wheel-motored electric vehicle (EV), and a model predictive controller is designed based on holistic control structure via active front steering and motor torque distribution. By designing a suitable reference model, the controller stabilizes a vehicle along the desired states while rejecting skid and fulfilling its physical constraints, so this is described as a constrained tracking problem. To solve this, the holistic control scheme is built to simplify the hierarchical structure of the controller and directly optimize the control inputs of system. Based on holistic control structure and MPC method, an objective function with constraints is designed over a receding horizon to meet the control requirements. Finally, the proposed nonlinear model predictive controller is evaluated on eight degrees of freedom (8DOF) EV model offline simulation platform. Simulation results of different road maneuver on slippery surfaces show the benefits of the control methodology used.     

A sensorless optimal control system for an automotive electric power assist steering system

This paper considers the analysis and design of a double-pinion-type electric power assist steering (EPAS) control system. A simplified model of the augmented steering assembly-electric motor system is developed using Lagrangian dynamics, and an optimal controller structure for the model is proposed. Three main advances to the state of the art are presented in this paper. First, a state-space design model is used rather than an input-output model. A state-space formulation for a system model that incorporates motor electrical dynamics is obtained with the assist motor angular position as the output. Second, linear quadratic regulator (LQR) and Kalman filter techniques are employed to arrive at an optimal controller for the EPAS system. The selection of weighting coefficients for the LQR cost function is discussed. Finally, the authors present a control strategy that eliminates the steering column torque sensor, a critical component in existing EPAS controller designs. The proposed control strategy presents an opportunity to improve EPAS system performance and also reduce system cost and complexity.     

An improved trajectory tracking decentralized adaptive controllerfor robot manipulators

A decentralized adaptive nonlinear controller for a robot manipulator is presented in this paper. Based on the promising results obtained by the decentralized adaptive PID control algorithms proposed by Seraji and other researchers, the authors redesigned the Lyapunov function, and as a result, achieved a further simplification of the control algorithm and better trajectory tracking performance. The main advantages of the proposed controller over similar controllers are the considerably faster convergence of tracking error, relatively simpler structure, and smoother control activity. Another advantage of this controller is that it only requires local position and velocity measurements, and it does not make use of the exact centralized mathematical model of the robot manipulator. Finally, the authors demonstrate through computer simulation the robustness of their controller against parameter variations and disturbances     

Modeling and Design of LiNbO3 Electro—optic Polarization Controller

A theoretical model for describing the operation of an electro—optical polarization controller on LiNbO3 is presented. The model can be used to optimize the device‘s structure and parameters to reach a specific polarization control. Meanwhile, some aspects on the design of an electro—optical polarizationcon troller are described.     

Fuzzy two-degrees-of-freedom speed controller for motor drives

A fuzzy two-degrees-of-freedom (2-DOF) controller and its application to the speed control of an induction motor drive are presented in this paper. The proposed controller is composed of two fuzzy controllers to obtain good tracking and regulating responses. Unlike the conventional fuzzy controller, the error between the outputs of a reference model and the controlled drive is used to drive the proposed fuzzy controller. The drive rotor speed response can closely follow the trajectory produced by the reference model, and good load speed regulating response can also be obtained simultaneously owing to the possession of two-degrees-of-freedom in structure. Moreover, these performances are rather insensitive to the operating condition changes. The dynamic signal analysis as well as the construction of fuzzy control algorithms are described in detail. Some simulated and measured results are provided to demonstrate the effectiveness of the proposed fuzzy controller     

Optimal Respiratory Controller Structures

It has been assumed that there exists an explicit "exercise stimulus" (i. e., a signal that is correlated to metabolic CO2 production and appropriately drives breathing). Alternatively, the behavior of the respiratory controller during exercise and inspiratory CO2 loading may be dictated by an optimal controller. The purpose of this paper is to examine the behavior of two alternative optimal controller configurations which do not require an explicit "exercise stimulus" for their operation. The first yields a multiplicative behavior between an exercise and airway CO2 load. The second yields an additive behavior between these two loads?a behavior consistent with that generally observed in man. Thus, an optimal controller structure may be part of the composite structure of respiratory control.     

Inverse model-based real-time control for temperature uniformity ofRTCVD

A reduced-order model describing a rapid thermal chemical vapor deposition (RTCVD) process is utilized for real-time model based control for temperature uniformity across the wafer. Feedback is based on temperature measurements at selected points on the wafer surface. The feedback controller is designed using the internal model control (IMC) structure, especially modified to handle systems described by ordinary differential and algebraic equations. The IMC controller is obtained using optimal control theory on singular arcs extended for multi-input systems. Its performance is also compared with one based on the Hirschorn inverse of the model. The proposed scheme is tested with extensive simulations where the full-order model is used to emulate the process. Several cases of significant uncertainty, including model parameter errors, process disturbances, actuator errors, and measurement noise are used to test the robustness of the controller to real life situations. Both controllers succeed in achieving temperature uniformity well within the desirable bounds, even in cases where several sources of uncertainty are simultaneously present with measurement noise     

Comments, with reply, on `An adaptive digital pump controller forphase-locked servo systems' by G.-C. Hsieh et al

It is shown that the linearized model of the adaptive digital pump controller utilized for studying stability conditions and used in the simulations in a previously published paper (see ibid. vol.34, no.3, p.379-86, 1987) does not agree with the proposed circuit. A reply from the authors of the original paper is also included     

Simulation of Semiconductor Manufacturing Supply-Chain Systems With DEVS, MPC, and KIB

The dynamics of high-volume discrete-part semiconductor manufacturing supply-chain systems can be described using a combination of Discrete EVent System Specification (DEVS) and model predictive control (MPC) modeling approaches. To formulate the interactions between the discrete process model and its controller, another model called Knowledge Interchange Broker (KIB) is used. A robust and scalable testbed supporting DEVS-based manufacturing process modeling, MPC-based controller design, and the ${hbox{KIB}}_{{{rm DEVS}/{rm{MPC}}}}$ interaction model is developed. A suite of experiments have been devised and simulated using this testbed. The flexibility of this approach for modeling, simulating, and evaluating stochastic discrete process models under alternative control schemes is detailed. The testbed illustrates the benefits and challenges associated with developing and using realistic manufacturing process models and process control policies. The simulation environment demonstrates the importance of explicitly defining and exposing the interactions between the manufacturing and control subsystems of complex semiconductor supply-chain systems.      

Bounding the capacity of saturation recording: the Lorentz modeland applications

The authors consider the problem of bounding the information capacity of saturation recording. The superposition channel with additive Gaussian noise is used as a model for recording. This model says that for a saturation input signal, x(t) (i.e., one that can assume only one of two levels), the output can be expressed as y(t)=x˜(t)+z(t ) where x˜(t) is a filtered version of the input x(t) and z(t) is additive Gaussian noise. The channel is described by the impulse response of the channel filter, h(t), and by the autocorrelation function of the noise. A specific example of such a channel is the differentiated Lorentz channel. Certain autocorrelation and spectrum expressions for a general Lorentz channel are derived. Upper and lower bounds on the capacity of saturation recording channels are described. The bounds are explicitly computed for the differentiated Lorentz channel model. Finally, it is indicated how the derived bounds can be applied in practice using physical measurements from a recording channel     

Robust H∞ control with multiple constraints forthe track-following system of an optical disk drive

In this paper, the authors design a tracking controller which satisfies transient response specifications and maintains tracking error within a tolerable limit for the uncertain track-following system of an optical disk drive. To this end, a robust H_∞ control problem, with regional stability constraints and sinusoidal disturbance rejection is considered. The internal model principle is used for rejecting the sinusoidal disturbance caused by eccentric rotation of the disk. The authors show that a condition satisfying the regional stability constraints can be expressed in terms of a linear matrix inequality (LMI) using the Lyapunov theory and S-procedure. Finally, a tracking controller is obtained by solving an LMI optimization problem involving two LMIs. The proposed controller design method is evaluated through an experiment     

T-S模型的模糊神经网络控制器及应用研究

本文介绍了Ｔ－Ｓ模型的模糊神经网络,讨论了这种网络的结构、学习算法,给出了由这种网络组成的控制器结构。仿真结果表明此控制器对船舶操纵等非线性系统具有很好的控制性能和鲁棒性。     

精确模型辨识的光电平台自抗扰控制器

针对实际工程中的复杂光电平台对控制精度要求越来越高的需求,提出一种依据系统精确模型辨识方法的自抗扰控制器设计方法。考虑机械谐振和摩擦因素,建立光电载荷控制系统精确数学模型,并根据系统输入输出特性辨识系统的数学模型参数,在所辨识模型的基础上设计自抗扰控制器。以某型光电跟踪平台为例,设计了4阶跟踪微分器,5阶扩张状态观测器和非线性状态偏差反馈控制律组合的自抗扰控制器。在Matlab/simulink中建立系统仿真平台,对PID控制器和自抗扰控制器进行仿真对比,结果表明,采用自抗扰控制器的系统超调由1.8%减小到0.9%,系统最大跟踪误差由0.03（）/s减小到0.013（）/s,超调更小,响应时间更快,抗扰动能力更强。     

Implementation of VSS control to robotic manipulators-smoothingmodification

The authors focus on the implementation of a variable structure systems (VSS) controller with smoothing laws in the design of effective tracking control for multi-input, multi-output robotic arms. The controller is realized by selecting powerful smoothing methods, such as balance conditions or their simplification, to reduce or remove undesirable chattering while keeping the robust characteristic that rejects system uncertainties. Giving careful consideration to actual system constraints, a design principle for selecting different smoothing methods is obtained and confirmed by experimental results     

A language for compositional specification and verification offinite state hardware controllers

The authors consider the state machine language (SML) for describing complex finite state hardware controllers. It provides many of the standard control structures found in modern programming languages. The state tables produced by the SML compiler can be used as input to a temporal logic model checker that can automatically determine whether a specification in the logic CTL is satisfied. The authors describe extensions to SML for the design of modular controllers. These extensions allow a compositional approach to model checking which can substantially reduce its complexity. To demonstrate these methods, the authors discuss the specification and verification of a simple central-processing-unit (CPU) controller     

Improving the ESD failure threshold of silicided n-MOS outputtransistors by ensuring uniform current flow

The authors describe and extend the present understanding of the high-current behavior of the simple single-poly finger n-MOS transistor. They present a model for the failure of the ladder structure n-MOS output device based on both the structure of the device and the behavior of its constituent n-MOS transistors. This model is able to show why the failure threshold of the output n-MOS device behaves as it does. Solutions that have been shown to improve the electrostatic discharge (ESD) failure threshold are described. The test environment and the process technology used for fabrication are described     

Implementation of a new MPEG-2 transport stream processor for digital television broadcasting

We introduce a real-time, dual independent output MPEG-2 transport stream (TS) processor designed specific for the China HDTV testing zones. The processor is a single piece of equipment, of which the core functions are realized in FPGA and DSP. Key technologies include a program clock reference (PCR) correction and a packets controller, which are important for TS processing, are described in detail. An improved PCR correction scheme developed by the authors is also proposed.