汽车电子系统电磁兼容设计与标准分析

伴随越来越多的高科技汽车电子产品的开发与应用,如何解决汽车电子系统的电磁兼容问题,提高汽车的可靠性和安全性,已经成为一个非常重要和迫切的研究课题。文章分析了汽车的电磁环境与电磁骚扰的危害,以及汽车电磁兼容性标准。     

Fuzzy control of nonlinear electromagnetic suspension systems

This paper presents a T–S model-based fuzzy controller design approach for electromagnetic suspension systems. The T–S fuzzy model is firstly applied to represent the nonlinear electromagnetic suspension systems. Then, based on the obtained T–S fuzzy model, a fuzzy state feedback controller is used to ensure the required mixed ℓ₂–ℓ_∞ performance of original electromagnetic suspension system to be achieved. This controller is designed in a nonparallel-distributed compensation scheme. And sufficient conditions for the existence of such a controller are derived in terms of linear matrix inequalities. Finally, numerical simulation on an electromagnetic suspension system is performed to validate the effectiveness of the proposed approach.     

The Electromagnetic Environment of an Automobile Electronic System

The objective of this paper is to report measured results of electric fields investigated inside the automobile. This investigation is important to the electronic design engineer before he starts the design of the different electronic systems needed to operate the automobile. By knowing the electromagnetic environment inside the automobile, the electronic engineer is given the opportunity to estimate and predict the various effects of electromagnetic disturbances on the automotive electronic systems. In our experiments, the work performed to study the electromagnetic environmental conditions was carried out on a typical midsize automobile with a high-power frequency-modulation (FM) transmitter installed inside the vehicle. Different antenna locations were used to radiate the electromagnetic waves that were studied. Data obtained from the experimental results are presented and discussed.     

汽车电子系统接地、屏蔽与滤波设计

伴随越来越多的高科技汽车电子产品的开发与应用,如何解决汽车电子系统的电磁兼容问题,提高汽车的可靠性和安全性,已经成为一个非常重要和迫切的研究课题。车载电子设备的增加使电磁骚扰问题凸现重要。寻找电磁骚扰源,采取接地、屏蔽、滤波等不同的抑制手段鼹决问题是我们今后研究的主要方向。     

汽车电子系统电磁兼容设计实践

伴随越来越多的高科技汽车电子产品的开发与应用,如何解决汽车电子系统的电磁兼容问题,提高汽车的可靠性和安全性,已经成为一个非常重要和迫切的研究课题。     

Modeling of Nonlaminated Electromagnetic Suspension Systems

Eddy currents induced within nonlaminated electromagnetic actuators by time-varying magnetic fields have a strong effect on the dynamics and control of electromagnetic suspension systems. This paper examines the modeling of these suspension systems and resolves two important problems: 1) the effect of time-varying flotor position on electromagnetic force production and 2) the proper manner in which to model voltage-mode operation of the suspension. The models developed are explicit functions of actuator material and geometric properties. The investigation focuses on axisymmetric cylindrical electromagnetic actuators. Similar results are provided for nonlaminated actuators with C-core stators. Experimental results are presented that demonstrate the accuracy of the modeling approach.      

Design,simulations and experimental investigations of a compact single mirror tip/tilt laser scanner

In this paper, we present the design aspects of a compact tip/tilt, fast steering laser scanner. The scanner is composed of one single mirror with a large active area, driven by linear electromagnetic actuators. The suspension of the mirror is based on a cone-ball bearing. Designing such a scanner requires a multi-disciplinary approach of the optics, mechanics, electromagnetic and control theories. Experimental results are presented as well to demonstrate the performance and effectiveness of the scanner developed. These results also serve to verify the analytical and simulated results.     

Design and implementation of a fault tolerant controller for EMS systems

Conventional EMS (electromagnetic suspension) systems are susceptible to instability problems, and could even break down upon failures of the air-gap sensor or the accelerometer. Therefore, in order to improve EMS performance, a fault tolerant controller and a fault detection and isolation (FDI) algorithm are presented in this work. The fault tolerant controller is an extended version of the linear fault tolerant controller designed for known actuator or sensor failures, and it adopts the LMI-based H_∞ control for a class of nonlinear systems. The fault detection algorithm employs fuzzy inference. The merits of the proposed control scheme have been verified by the experiments with a single-axis two-magnet suspension system subjected to failures of the actuator or the sensors.     

Automotive electrical systems circa 2005

Demands for better fuel economy and more electric power are driving cars to multiple higher voltages. In the next 10 years the electrical systems in some luxury automobiles will be so changed as to be almost unrecognizable. Although they will doubtless employ the old reliable 12 V lead-acid battery, their loads will be driven by a variety of voltages, both AC and DC, perhaps derived from a single AC distribution network. Designers will be able to match voltages to individual loads for best efficiency and performance-lights perhaps at 6 V AC, electronics at 5 V DC, active suspension at 350 V DC, and motors and actuators at 42 V DC. The digital signals controlling those loads will be carried by a separate communications network. The enabling technology for these advances are semiconductors. The authors discuss the future development of automobile electrical systems     

Vibration control for active seat suspension systems via dynamic output feedback with limited frequency characteristic

This paper investigates the problem of H_∞ control for active seat suspension systems via dynamic output feedback control. A vertical vibration model of human body is introduced in order to make the modeling of seat suspension systems more precise. Meantime, different from the existing H_∞ control methods which conduct disturbance attenuation within the entire frequency domain, this paper addresses the problem of H_∞ control for active seat suspension systems in finite frequency domain to match the characteristics of the human body. By using the generalized Kalman-Yakubovich-Popov (KYP) lemma, the H_∞ norm from the disturbance to the controlled output is decreased over the chosen frequency band between which the human body is extremely sensitive to the vibration, to improve the ride comfort. Considering a practical situation of active seat suspension systems, a dynamic output feedback controller of order equal to the plant is designed, where an effective multiplier expansion is used to convert the controller design to a convex optimization problem. Compared with the entire frequency approach for active seat suspension systems, the finite frequency approach achieves better disturbance attenuation for the concerned frequency range, while the performance constraint is guaranteed in the controller design, which is verified by a practical example with certain and random road disturbances.     

车载系统底盘电气电磁干扰研究（上）

随着车载系统的发展,上装电子设备越来越多,系统的电磁干扰问题日益突出,作为车载系统的一个主要部分——汽车的底盘的电磁干扰问题很值得研究。文章通过对汽车底盘电气结构和特征的分析,进一步分析了汽车底盘电气电磁干扰特性,最后对汽车底盘电气电磁干扰的抑制方法进行了介绍。     

关于汽车电磁兼容性技术要求

汽车电磁骚扰的测量和限制关系到汽车运行的可靠性，安全性，经济性。本文介绍国家标准GB18655-2002，对汽车及其零部件产生的各种电磁骚扰以限值形式体现的技术要求。     

Effect of body gaps on conformal automotive antennas

The electromagnetic effects of the hood, trunk and door gaps of an automobile body are discussed. The results of a set of theoretical simulations and experimental measurements are presented to show the impact of such gaps on the input impedance gain patterns of automobile conformal antennas.     

中低速磁浮列车悬浮供电系统测试与分析

作为中低速磁浮列车的关键设备,悬浮供电系统是决定悬浮控制系统能否稳定可靠工作的前提。通过介绍电磁型中低速磁浮列车的悬浮供电系统基本结构和工作原理,以某型样车为研究对象,制定了多工况测试方案,对悬浮供电系统的主电源、蓄电池和超级电容组等的性能开展了详细测试。为进一步开展中低速磁浮列车各主要功能模组的多工况性能测试提供了参...     

Linear electromagnetic actuator modeling for optimization of mechatronic and adaptronic systems

In active mechanical systems (mechanisms or structures) the possibility of a coupling between active and passive elements at an early stage of the design process is becoming more and more significant. In order to integrate actuators in preliminary design procedures or in a multidisciplinary optimization approach, reliable models of the actuator performance (actuator force and stroke, loading curves, strength limit, volume and mass specific work and power, frequency range, efficiency) as a function of the design parameters and variables (actuator principle, size of the actuator element) are necessary. The present work deals with the formulation of model-based design rules to be used in the conception of optimized mechatronic and adaptronic systems and applies it to linear electromagnetic actuators optimization focusing on the solenoid and moving coil actuators.     

Integrated tilt with active lateral secondary suspension control for high speed railway vehicles

This paper presents a novel active suspension control configuration for high speed tilting railway vehicles which integrates tilt with active lateral secondary suspension. The use of the active lateral secondary suspension is to attenuate the vehicle body lateral vibration on straight track, while complementing tilt action during curving. Various control strategies are proposed to accommodate both tilt and active lateral suspension multiple design requirements, whilst considering the strong interaction between vehicle body roll and lateral modes. Compared with the commercial solutions for tilt control, the proposed integration strategy improves the tilting control performance both on curved and straight track as illustrated by simulation tests and control assessments based on given track profiles.     

Pseudolinear estimation of fractionally integrated ARMA (ARFIMA)models with automotive application

A novel pseudolinear method for the estimation of fractionally integrated ARMA (ARFIMA) models that are capable of representing combined long- and short-term dependency, is introduced. The method is based on the relationship of the AR/MA parameters and the coefficients of the fractional power operator binomial series expansion with the model's inverse function. These lead to the formulation of a special-form regression problem that can be decomposed into a univariate nonlinear and a multivariate linear regression and may be thus tackled via a special pseudolinear procedure. This decomposition in turn leads to the elimination of the need for initial guess parameter values, drastic simplification in the detection and handling of potential local extrema problems, as well as computational simplicity. The method's strong consistency is established, whereas its performance characteristics are assessed via Monte Carlo experiments and comparisons with the maximum likelihood method. The pseudolinear method is also used for the ARFIMA modeling and prediction of power consumption in an experimental automobile fully active suspension system, the consumption of which is shown to exhibit long-term dependency. A comparison with ARMA/ARIMA type modeling is also made, and the obtained ARFIMA models are shown to achieve improved predictive performance at a drastically reduced parametric complexity     

Ultra precision motion control of a multiple degrees of freedommagnetic suspension stage

A general framework for ultra precision motion control of magnetic suspension actuation systems with large travel ranges in multiple degrees of freedom (DOF) is presented. It encompasses the development of nonlinear electromagnetic force model for 6-DOF actuation, and the design of the necessary control architecture for ultra precision motion control of magnetic suspension actuation systems. A 6-DOF magnetic suspension stage (MSS) was designed and fabricated to illustrate the developed framework. The MSS consists of multiple electromagnets that are located around the flotor and are utilized to suspend and modulate its position and orientation. The control architecture takes the six control parameters provided by a laser measuring system and intends to control the 6-DOF motion by regulating the current in the electromagnets. The developed robust nonlinear control architecture consists of three components: 1) feedback linearization; 2) force distribution; and 3) H_∞ robust controllers for each DOF of motion. Several experiments are designed to illustrate the desired characteristics of the developed system     

Closed-loop performance of a six degree-of-freedom precision magnetic actuator

The slotless permanent-magnet self-bearing motor (SBM) technology is used to fully provide radial bearing and motoring functionality simultaneously in a six degree-of-freedom magnetic actuator for potential precision pointing and tracking applications in space such as intersatellite laser communications. This novel precision magnetic actuator incorporates two SBMs to produce both radial bearing forces and motoring torque, and one active magnetic bearing to provide axial support, and thus allows for a complete electromagnetic suspension and precision noncontact pointing. An analytical representation of the overall dynamic system is presented for controller design. Six decoupled proportional-integral-derivative controllers are designed, and a feedback control system is implemented. The closed-loop performance confirms experimentally that the precision magnetic actuator is capable of smooth angular slewing while maintaining good stabilization. The most encouraging result is that the actuator achieves a high angular resolution of 754 nrad over a large azimuth range of /spl plusmn/45/spl deg/.