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1.
边界扫描测试技术是目前一种主流的可测性设计方法,它用特有的结构和检测方法克服了复杂数字电路板测试的技术障碍,深入研究了IEEE1149.1边界扫描标准,文章针对传统的边界扫描测试控制器的接口复杂度高,边界扫描测试控制器硬件复杂、成本高的缺点,提出了一种基于USB2.0接口的边界扫描测试控制器设计方案,设计USB接口电路及驱动程序;测试结果表明,该测试控制器产生的测试信号符合IEEE1149.1标准。同时该控制器具有硬件结构简洁,使用灵活,有较高的性价比的特点,有较好的应用前景。  相似文献   

2.
随着电子技术的日益发展,电子电路系统的集成度和复杂度越来越高,边界扫描技术应用的越来越广泛。机载电子设备可测试性设计成为飞机设计的重要组成部分,随着电子技术的日益发展,机载电路板的集成度和复杂度越来越高,传统测试方法难以满足需要。本文根据边界扫描IEEE1149.1标准,采用Atmega128单片机以及SN74ACT8990构成边界扫描测试系统模块图构建基于SOPC边界扫描的航空发动机电子控制器的检测,通过检测可以实现功能。  相似文献   

3.
随着试飞技术的发展,网络化测试技术已经应用到试飞测试工程中,针对该网络化测试系统时间精确同步这一难题,文章设计和构建了基于IEEE1588标准的试飞网络化机载数据采集系统,以及该标准如何在分布式数据采集系统中实现系统的同步采集功能,成功地解决了某工程试飞测试领域中网络化测试系统的时钟精确同步的关键技术。  相似文献   

4.
该系统是用STC89C52微型控制器发生PWM信号后输出给全桥电路来达到调节直流电机的转速。单片机的6个引脚与附带的6个外接按键相连接,对这6个外接引脚进行不断扫描,由按键的不同状态,使单片机发出不一样的命令,产生不同的PWM信号,同时将产生的PWM信号用于输入信号输入全桥电路,然后以全桥电路的输出作用于直流电机上的电压输入,从而实现控制电机的不同运转状况。  相似文献   

5.
梁晓阳  张林 《科技通报》2013,29(2):73-75
设计无线传感器网络要考虑到传输速率、应用环境情况及数据可靠性等因素.本文设计了基于无线传感器网络的电机运行状态监测系统的基本框架,选择了2.4 GHz频段以及IEEE802.15.4作为通信频段与通信标准,设计了适宜的网状拓扑结构.为提高数据传输速率以及正确性,本系统采用了有时隙的CSMA/CA的无线传感器网络MAC协议,有效地减少了网络中的信号冲突.最终实现了电机监测能量限制较小、可靠性要求高、数据传输速率要求快的要求.  相似文献   

6.
在现代工程实践中,伪随机序列广泛应用于信息安全、数字通信、密码学、自动控制等领域中。本文设计了一种基于TD-ERCS混沌系统和混沌序列均匀化普适算法的伪随机序列发生器;采用32位高性能浮点型数字信号处理芯片实现了IEEE754双精度浮点型标准的PRSG;DSPs与PC的通讯采用了USB2.0传输协议。依据美国国家标准与技术研究院所提出的伪随机序列性能指标,对迭代所产生的混沌伪随机序列进行了测试,结果表明该PRSG所产生的CPRS性能良好,为算法的硬件实现做了很好的前期验证。  相似文献   

7.
OFDM技术以其具有的抗窄带干扰和抗频率选择性衰落等优点,被4 G和5 G采用为核心技术,代表了未来无线通信的发展方向。本文通过对OFDM技术的研究,以Xilinx FPGA为硬件平台,基于IEEE802.11a协议设计了OFDM接收系统的FPGA实现方案。测试结果表明,该接收系统能够正确恢复出经过干扰的信号域和数据域信息,并在FPGA上实现,对OFDM系统的硬件实现具有重要的参考意义。  相似文献   

8.
柴华  谈恩民  江志强 《大众科技》2012,14(3):33-35,39
随着集成电路规模的不断扩大,基于IP核复用的SoC设计技术被广泛应用,但是由于IP核的来源不同,使得SoC的测试变得越来越困难。IEEE Std 1500给IP核提供商与用户之间提供了标准的测试接口,简化核测试信息的复用。文章基于此标准设计了SoC中存储器的Wrapper测试壳结构和BIST控制器,以DRAM和SRAM为测试对象进行验证,结果表明了在不同测试指令和故障模式下,测试壳和控制器的有效性。  相似文献   

9.
本文设计的多功能键盘显示控制器,可以完成直连键盘、矩阵键盘以及LED数码管动态扫描的全部工作,并且实现按键的识别以及自动连续功能,实现LED数码管的显示、闪烁以及小数点控制等功能,同时该控制器对外接口采用了常规的UART接口,制定了完善的通信协议,可实现键值的获取和对显示的控制。该多功能键盘显示控制器不但克服了传统单片机系统占用较多的I/O口线和系统资源的缺点,而且采用比较主流的现场可编程门阵列FPGA,功能灵活,使用方便。  相似文献   

10.
ATLAS语言在某型号发射装置测试程序中的应用   总被引:1,自引:0,他引:1  
ATLAS是“所有系统的缩略测试语言”的英文缩写,由IEEE标准部门以IEEE Std 716标准颁布。该语言可以使每个被检测单元的测试程序开发独立于测试资源和测试设备,具有可移植性强、可读性好等特点。通过介绍ATLAS在某型号发射装置测试程序中的应用,说明ATLAS语言的开发要点和优越性.供初学者参考。  相似文献   

11.
方磊  马善农 《科技广场》2004,(10):31-32
本文主要介绍以CPLD芯片进行十字路口的交通灯的设计,用CPLD作为交通灯控制器的主控芯片,采用VHDL语言编写控制程序,利用CPLD的可重复编程和在动态系统重构的特性,大大地提高了数字系统设计的灵活性和通用性。  相似文献   

12.
In this paper, an adaptive Takagi–Sugeno (T–S) fuzzy controller based on reinforcement learning for controlling the nonlinear dynamical systems is proposed. The parameters of the T–S fuzzy system are learned using the reinforcement learning based on the actor-critic method. This on-line learning algorithm improves the controller performance over the time, which it learns from its own faults through the reinforcement signal from the external environment and tries to reinforce the T–S fuzzy system parameters to converge. The updating parameters are developed using the Lyapunov stability criterion. The proposed controller is faster in learning than the T–S fuzzy that parameters learned using the gradient descent method under the same conditions. Moreover, it is able to handle the load changes and the system uncertainties. The test is carried out based on two mathematical models. In addition, the proposed controller is applied practically for controlling a direct current (DC) shunt machine. The results indicate that the response of the proposed controller has a good performance compared with other controllers.  相似文献   

13.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   

14.
This paper deals with the load frequency control problem of multi-area power system with doubly-fed-induction-generator-based wind farm. An area-based event-triggered (ET) sliding mode control scheme is proposed to restore the nominal frequency by transmitting less information. The main feature of area-based ET scheme is that each area will transmit its states information to the controller independently via its own triggering mechanism. By flexibly selecting triggering thresholds, the area-based ET scheme can meet the unbalanced network resources among different areas. Meanwhile, the designed sliding mode controller can effectively suppress the fast fluctuation resulting from load and wind generation to achieve frequency restoration and maintain the tie-line power at its scheduled value. The optimization algorithm on the sufficient conditions is given. Finally, the proposed control scheme is illustrated via a three-area power system and IEEE 39-bus system.  相似文献   

15.
In this study, an adaptive interval type-2 Takagi-Sugeno-Kang fuzzy logic controller based on reinforcement learning (AIT2-TSK-FLC-RL) is proposed. The proposed controller consists of an actor, a critic and a reward signal. The actor is represented by the IT2-TSK-FLC in which the antecedents and the consequents are interval type-2 fuzzy sets (IT2FSs) and type-1 fuzzy sets (T1FSs), respectively, which are named A2-C1. The critic is represented by a neural network, which approximates the optimal guaranteed cost in the control design to ensure the system stability for all admissible uncertainties and noise. The use of a reward signal to formalize the idea of a goal is one of the most distinctive features of RL. Thus, the proposed controller evolves in time as a result of the online learning algorithm. The parameters of the proposed controller are learned online based on the Lyapunov theorem to guarantee the stability, overcome the shortcomings of the gradient descent, such as the local minima and instability, and determine the learning rate of the IT2-TSK-FLC controller. Furthermore, the critic stability is discussed for determining the optimal learning rate. The proposed controller is applied to uncertain nonlinear systems to show its robustness in reducing the effect of system uncertainties and external disturbances and is compared to other controllers.  相似文献   

16.
17.
根据IEEE 802.11协议在链路层提供有限次数链路重传的特点,提出了一种在基于IEEE 802.11的移动Ad Hoc网络(MANET)中保证可靠通信的节能路由改进算法——ERRC(Energy-efficient Routing algorithm for Reliable Communication in IEEE 802.11-based MANET),它可以方便地应用于MANET中现有的反应式路由协议。ERRC分析并建立了适合于IEEE 802.11情况的重传模型和能耗模型,提供了在发送数据分组时的功率控制机制,在节点选路时综合考虑了分组错误概率、节点代价函数的影响。仿真结果表明,ERRC算法可以显著提高网络生存期,在节省能耗方面比没有考虑分组错误概率的节能路由算法更为精确。  相似文献   

18.
To achieve accurate position control of electro-hydraulic asymmetric cylinder system with only available displacement signal, an output feedback controller is proposed in this paper. The dynamic model of the system is expressed as a Brunovsky form, which helps to estimate the system states and simplify the controller structure. Then Levant differentiator is introduced to estimate the position, velocity and acceleration of the asymmetric cylinder system based on the output signal, which can reduce the impact of measurement noise compared to the means of calculating the time derivative of the displacement signal directly. Besides, a high gain disturbance observer is designed to reject the lumped disturbance rejection of the system including parameter uncertainty, modelling error and external disturbance. Moreover, a sliding mode surface is introduced to the controller design and a robust item with continuous function is applied to compensate for estimation errors. According to Lyapunov theory, the developed output controller is pledged to be stable that can realize disturbance rejection control as well as backstepping-free control. Furthermore, a large-size asymmetric cylinder experimental rig is set up to simulate practical applications environment. Comparative experimental results reveal the validity and potential practical meaning of the developed control approach.  相似文献   

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