基于ADuC841单片机的燃料电池电子负载控制器设计

针对燃料电池电子负载的特点和控制需求,该文设计了一种基于ADuC841单片机的燃料电池电子负载控制器,重点介绍了PID算法、控制器硬件电路及相应软件的设计方法,并通过实验验证了其可行性和有效性。研制的控制器具有体积小、使用方便、控制精度高等特点,已批量生产应用。

静态负载控制器在跨座式单轨车辆调试中的应用

介绍了静态负载控制器的组成、使用方法、注意事项及在重庆跨座式单轨车辆调试中的应用。

基于负载通告的SDN多控制器负载均衡机制

多控制器负载均衡是SDN网络部署研究中关注的问题之一。该文针对多控制器间负载均衡的时间效率问题,提出一种基于负载通告策略的负载均衡机制(LILB)。该机制包括负载测量、负载通告、均衡决策和交换机迁移4个核心功能组件。借助于负载通告的能力,每个控制器可以在过载后无需收集其他控制器的负载信息而尽快完成均衡决策。为了减少负载通告带来的通信负荷和处理负荷,该文提出一个抑制算法来降低负载通告的频率。此外,该文还提出了最重过载控制器、迁移交换机和目标控制器的决策方法,以及目标控制器接受迁移请求的判定策略来避免控制器的负载震荡;并为支持交换机迁移过程中控制器角色的平滑切换设计了一种交换机迁移的消息交互机制。最后,在基于Floodlight和Mininet的实验环境中验证了所提出方法的有效性。

一种基于离散变结构控制的负载频率控制器

提出了一种等式到达条件下的离散变结构组合控制策略 ,设计了基于该控制策略的负载频率控制器。仿真结果显示它能显著改善系统的动态性能 。

负载频率控制器的最优控制及仿真研究

本文对负载频率控制器实施了最优控制并进行了仿真研究，这种工作对提高整个电力系统的运行可靠性和稳定性是非常有意义的。

负载仿真控制器的存储器扩展技术

80C196KC是Intel公司生产的CHMOS高性能低功耗16位单片机。本文主要介绍了它的主要性能特点,讨论了其在存储器扩展方面的设计方法,并结合负载仿真控制器的系统应用,给出了程序存储器、数据存储器扩展系统图和相应的控制电路图。

基于时延与负载的SDN控制器部署模型

为在软件定义网络架构中对多控制器进行合理部署,考虑时延、负载和成本三方面因素,对交换机的平均流安装时延和控制器负载方差进行建模,提出一种多控制器部署模型及其求解算法,并基于粒子群优化(PSO)算法和模拟退火算法获取最佳控制器部署方案。仿真结果表明,在部署相同数量的控制器时,相对PSO算法和随机部署算法,该算法的平均流安装时延更短,控制器负载方差更小。

基于贝叶斯网络的SDON控制器自学习负载均衡算法

随着软件定义光网络(SDON)规模的增大,需多个控制器共同为全网提供服务,而控制器负载均衡问题影响到全网服务能力和网络生存性。提出一种基于贝叶斯网络的SDON控制器自学习负载均衡算法。首先,在考虑控制器负载、控制器吞吐量和光交换机迁移时延等控制器相关参数的情况下,利用贝叶斯网络预测负载拥塞程度;其次,结合强化学习算法作出最优动作决策,并利用反馈机制实现参数权重的自我调节,从而调整控制器负载拥塞程度实现负载均衡。仿真结果表明:与Q-learning算法相比,该算法更好地实现了控制器负载均衡功能,更快地提高了负载均衡效率。

SDN中区分交换机等级的控制器负载均衡算法

针对软件定义网络(Software Definition Network,SDN)多控制器负载不均衡问题,提出基于Q-learning算法区分交换机等级的SDN控制器负载均衡算法。依据交换机所影响网络资源划分等级,在进行控制器负载均衡的同时避免高等级交换机连接至同一控制器,提升全网络生存性。仿真结果表明:该算法可以有效地实现控制器负载均衡功能,同时可以有效根据控制器等级进行迁移分配,限制了单个控制器故障对全网资源的影响,提升了网络生存性。

SDN中基于动态迁移优化的控制器负载均衡算法

为了改善软件定义网络(Software Defined Network,SDN)中由于流量突变引起的多控制器负载不均衡的问题,提出一种基于动态迁移优化(Dynamic Migration-Optimized Load Balancing,DMOLB)的控制器负载均衡算法。该算法在控制器负载阶段以常规控制器的负载作为过载的判断依据。选择迁移域阶段通过选出的迁入域减少交换机迁移的开销。在设定子域迁移度和有效期阶段基于选出的迁移域设定子域迁移度和交换机有效期,计算迁移交换机的数量,并在有效期内完成交换机协调迁移。仿真结果表明,与负载通告(Load Informing based Load Balancing,LILB)算法和阶段式控制器负载均衡(Stage Controller Load Balancing,SCLB)算法相比,该算法降低了交换机迁移通信开销,提高了控制器的资源利用率。

负载分配控制器提高多模块并联电源的性能及可靠性

随着集成电路的工作电压不断降低,要保持电子产品的功率不变,则所需的电流越来越大。近年来开发出各种新型低电压、大电流的电源,以满足这种发展的需要。 在电源系统中常有这样的设计,将多个DC/DC变换器模块并联起来以满足所需的大电流输出。这种设计十分灵活,根据不同的输出电流,采用不同数量的并联模块。

小波分析在线性负载仿真控制中的应用

通过小波、尺度函数与多分辨率的理论分析,对线性负载仿真控制器机组转速信号进行了时频局部化分解,发现奇异点的位置和空间分布状况,可精确地描述信号的局部奇异性,为故障诊断提供了新的技术和方法。

单负载-双电源自动切换控制及其缺相保护

介绍具有缺相保护的单负载-双电源自动切换控制。其具有对三相供电电源的缺相检测及保护切换功能,在电源恢复正常后能自动进行反切换,当发生故障和恢复正常时,能分别发出两种区别明显的报警和提示音响,功能完备,性能稳定可靠。

单片仿真技术在元器件安全性检测中的应用

文中通过对单片微计算机基本运用原理的分析,介绍了利用单片仿真技术设计和制造单片控制器在实验室安全检测工作中应用的实例。

Fractional order integral sliding mode control for PMSM based onfractional order sliding mode observer

In view of the variation of system parameters and external load disturbance affecting the high-performance control of permanent magnet synchronous motor(PMSM),a fractional order integral sliding mode control(FOISMC)strategy is developed for PMSM drive system by means of fractional order sliding mode observer(FOSMO).Based on FOISMC technology,a fractional order integral sliding mode regulator(FOISM-based regulator)is designed,and a global integral sliding mode surface design method is presented,which can guarantee the global robustness of the system.Combining fractional order theory and sliding mode control theory,the FOSMO is constructed to achieve better identification accuracy of the speed and rotor position.Meanwhile the sliding mode load observer is used to observe the load torque in real time,and the observed value is transmitted to speed regulator to improve the capability of accommodating the challenge of load disturbance.Simulation results validate the feasibility and effectiveness of the proposed scheme.

Digitally Controlled Boost PFC Converters Operating with Large Scale Load Fluctuations

When boost power factor correction(PFC) circuit works with large scale load fluctuations, it is easy to cause a higher total harmonic distortion and a lower power factor because of traditional controllers and inductor current mode. To solve this problem, this paper proposes a PFC control system, which can operate with load fluctuations up to 1 000 W by using duty cycle feed-forward control theory to achieve smooth switching mode. The duty cycles in the next period of the control system are pre-estimated in the current cycle, which enhances the speeds of AD samplers and switching frequency, and reduces the cost and volume of the equipment to some extent. Introductions of system decoupling and feed-forward of input-voltage greatly improve the system performance. Both theoretical simulation and experimental results prove the advantage of the proposed scheme.

1.0 V low voltage CMOS mixer based on voltage control load technique

A CMOS active mixer based on voltage control load technique which can operate at 1.0 V supply voltage was proposed, and its operation principle, noise and linearity analysis were also presented. Contrary to the conventional Gilbert-type mixer which is based on RF current-commutating, the load impedance in this proposed mixer is controlled by the LO signal, and it has only two stacked transistors at each branch which is suitable for low voltage applications. The mixer was designed and fabricated in 0.18 tam CMOS process for 2.4 GHz ISM band applications. With an input of 2.44 GHz RF signal and 2.442 GHz LO signal, the measurement specifications of the proposed mixer are： the conversion gain （Gc） is 5.3 dB, the input-referred third-order intercept point （PIIP3） is 4.6 dBm, the input-referred 1 dB compression point （P1dB） is --7.4 dBm, and the single-sideband noise figure （NFSSB） is 21.7 dB.

Nonlinear dynamic fractional sliding mode control to the motor of mining locomotive

The harsh operating environment and complex operating conditions of the mine electric locomotive affect the control performance of the locomotive traction motor.In order to improve the speed control performance of electric locomotive traction motors,a dynamic fractional-order sliding mode control(DFOSMC)algorithm considering uncertain factors was proposed.A load torque sliding mode observer was designed for the complex load disturbance of the traction motor,and its observations were integrated into the DFOSMC controller to overcome the influence of load disturbance.Finally,the stability of the designed controller was proved by Lyapunov's theorem.Besides,the control performance of DFOSMC controller was compared with integer-order sliding mode controller and fractional-order sliding mode controller through simulation experiments.Compared with integer-order sliding mode and fractional-order sliding mode controllers,the dynamic and static performance of the DFOSMC controller with load observation is better,and it has stronger anti-interference ability.The DFOSMC controller effectively improves the control performance of the traction motor of the mining locomotive.

Formation control for networked spacecraft in deep space

In this paper, two formation controllers are developed under directed and undirected communication topology for six-degree-of-freedom （6-DOF） networked spacecraft flying in deep space. In the control algorithm, any explicit leader does not exist in the formation team and the proposed controller is required that each spacecraft communicates with its neighbors only, which avoids having to communicate each spacecraft＇s trajectory and therefore reduces the required communication loads of the whole formation. The proposed control strategy allows that each spacecraft can track its desired position and attitude and simultaneously the whole group moves to the desired formation and obtains its desired relative attitudes between spaceerafts. Simulation results demonstrate the effectiveness of the proposed controller.

Advance Electronic Load Controller for Micro Hydro Power Plant

Most of the MHP （micro hydro power） plants use ELC （electronic load controller） for speed control. Various types of ELC have been developed so far. A dummy ballast load is connected across each phase of generator terminals and ELC controls the power consumed by the ballast load to result in constant speed operation. The ELC developed so far uses thyristor switches in each phase to control ballast load power. The ELC senses the system frequency and comparing it with reference frequency, it generates a common value of firing angle for all three thyristor pairs of each phase. The performance of such ELC is not perfect for unbalanced consumers load connected in each phase, which overloads the generator. This paper presents an advanced type of ELC which senses frequency as well as consumer＇s load current of each phase and fires the thyristor pairs with different value of firing angles for different phases. This solves the problem of overloading of the generator with unbalanced consumer＇s load. Simutink model is developed to perform transient analysis of the proposed scheme and the prototype of hardware is also fabricated. The simulation results and experimental results are presented.