基于GPS技术的电力系统同步相量测量装置

提出了一种采用全球定位系统(GPS)同步相量测量装置(PMU)的硬件方案。其设计基于双DSP结构，具有高速的运算能力和丰富的外围电路，并配置了网络接口，通信方便，可以实现电力系统大量节点的同步相量测量。叙述了PMU的原理、结构以及在电力系统中的应用。     

基于相量测量的等效电流量测变换状态估计的研究

针对同步相量测量单元(PMU)测量的特点,分析了引入PMU测量值对电力系统状态估计的影响,引入PM U量测信息的状态估计模型.在该等效电流量测变换状态估计模型的基础上引入旋转变换,不需对电压的相角和幅值及有功和无功的量测权重作出任何假设,即可实现方程的实、虚部严格解耦.同时,该方法可以充分利用PMU的信息, 包括支路电流相量量测,并且所需的存储量较小、计算速度较快和计算精度高,具有较好的工程应用前景.     

参数未知环境下PMU装置相角差校准方法设计

PMU装置相角量测的准确性将直接影响相角差校准的有效性,且在参数未知环境下,相角量测的误差将有所增大.为此,文中设计一种面向参数未知环境的PMU装置相角差校准方法.根据PMU装置的内部结构建立测量装置ms级的内守时钟,结合互感器、采样保持器和比较器获得相位,并计算相量,再根据相位和相量获得相角值与周期同步时标的偏移量,...     

基于改进EKF的DC/DC转换器电感电流观测器

为了减小电磁干扰(Electromagnetic Interference,EMI)引起的DC/DC转换器输出电压噪声,消除负载变化引起的稳态误差,提出了一种基于改进的扩展卡尔曼滤波器(Extended Kalman filter,EKF)的电感电流观测器.首先,介绍了Boost型转换器的状态空间方程和扩展卡尔曼滤波器;之后提出负载估算算法,对EKF进行改进.利用改进EKF的输出电压、电感电流和占空比即可估算出实际负载值,从而实时更新改进EKF的参数,使电流观测器可以准确估计电感电流;最后对提出的电流观测器进行了仿真验证.仿真结果表明,在负载突变时,改进EKF可以对EMI引起的输出电压噪声进行有效滤波,同时准确估计电感电流,保证了DC/DC转换器输出电压的准确性.     

一类MIMO非线性系统的自适应模糊输出反馈控制

针对一类MIMO非线性状态不可测系统,提出了一种稳定的基于观测器的自适应模糊控制方法.该方法不需要系统状态可测的条件,而是通过设计模糊观测器来估计系统的状态.证明了所提出的控制方法可保证闭环系统的稳定性和跟踪误差的收敛性.仿真结果进一步验证了该控制方法的实用性和有效性.     

基于ESO的三相PWM整流器电流滑模控制研究

为解决三相PWM整流器在电流滑模控制下的高性能与电流抖振之间的矛盾,提出了一种基于扩张状态观测器(ESO)的新型电流滑模控制方案.采用扩张状态观测器观测系统的总扰动,构建新的滑模控制趋近律,将扰动观测值补偿进滑模控制律中,采用空间矢量脉宽调制的方法产生开关信号,提高系统抗扰动能力的同时削弱电流抖振.仿真和实验结果表明,...     

非线性离散时间系统的自适应函数观测器

针对一大类非线性离散时间系统提出了一种自适应函数观测器(AFO)。通过引入状态变换，得到了一类降阶形式的状态估计问题。采用一种稍加修改的强跟踪滤波算法估计降阶状态向量，然后利用降阶状态向量估计非线性状态函数。给出了AFO局部渐近收敛的充分条件。数值仿真示例显示AFO是一种具有强跟踪性质的自适应观测器，能在估计非线性状态函数的同时准确估计未知时变参数。     

基于eCAN和以太网的同步旧量测量装置通信方案设计

文章在基于数字信号处理器（DSP）和高速AVR单片机双CPU的同步相量测量装置（Phasor Measurement Unit,PMU）的基础上,研究TeCAN总线（Enhanced Controller Area Network）与工业以太网相结合的PMU数据通信方案。设计了基于高性能数字信号处理器TMS320LF2407的连接CAN现场总线和工业以太网的嵌入式现场网关,实现了PMU与现场工控机以及远程控制中心的实时通信。     

一种直线同步电机的控制方法

针对直线同步电机(LSM)控制系统,提出一种基于观测器的鲁棒控制方法。该方法首先建立了LSM矢量控制模型。然后利用李亚普诺夫方法,给出基于状态观测器的闭环控制系统鲁棒渐近稳定的充分条件,利用线性矩阵不等式处理方法,获得观测器和反馈控制器的参数。最后通过数值仿真,实验结果优于传统的控制方法,验证了该方法的正确性。     

扩张状态观测器下的自适应输出反馈控制

针对一类不确定非线性系统,研究了一种结合反步法和自抗扰控制的新的自适应输出反馈控制方法.通过引入扩张状态观测器(ESO)对被控系统的未知状态进行实时估计,同时利用扩张状态观测器实现对系统中的不确定项在线逼近及补偿.通过非线性滤波器对反步法设计过程中的虚拟控制信号进行求导,避免了传统反步法设计控制中复杂性爆炸的问题,并由...     

基于功角测量和等面积法则的发电机暂态稳定在线判别研究

基于相量测量单元(PMU)的广域测量系统将电力系统的安全稳定监测提高到了动态水平,其中一个关键功能是发电机功角的直接测量.本文将功角测量和等面积法则相结合,用以快速判别电力系统的暂态稳定.该方法能够在线实时判别电网故障的发生和切除、根据实测功角数据计算加速面积、预测最大可能的减速面积,从而根据加速面积和减速面积的差值来判断暂态稳定性.该方法预测耗时短,可在故障切除后80ms内给出判断结果并提供稳定裕度信息.仿真结果一方面证明了其可行性;另一方面也表明,受PMU本身数据上传速率的影响,加速面积的预测值可能偏小,当加速面积和减速面积非常接近时,应采用其他辅助分析手段协助判别暂态稳定性.     

Decentralized nonlinear adaptive control for multimachine power systems via high-gain perturbation observer

This paper presents two novel decentralized nonlinear adaptive controllers (DNAC) for large-scale interconnected power systems, via state-feedback and output-feedback strategies respectively. In the both controllers, system perturbation, which includes all subsystem nonlinearities and interactions between subsystems, is estimated by a high-gain observer and then involved the decentralized adaptive feedback linearizing control law. For the first DNAC, when all subsystem states are available, a second-order high-gain perturbation observer is designed to estimate the system perturbation, which leads to a decentralized nonlinear adaptive state-feedback controller. For the second, a decentralized nonlinear adaptive output-feedback controller is designed using a high-gain states and perturbation observer, when only one subsystem state is measured. The stability of the closed-loop controller/observer system is analyzed by the Lyapunov direct method. Both the controllers have been evaluated in a simulation study based on a three-machine power system. The results show that with a simple structure, both the controllers have robust performance of improving the transient stability and damping of multimode oscillations, under different power-system operation and fault conditions.     

一类非线性互联系统的H∞模型参考跟踪分散输出反馈模糊控制

本文对一类不确定状态不可测非线性互联系统,给出了一种基于观测器的H_∞模型参考跟踪分散输出反馈模糊控制方法.设计中,首先采用模糊不确定T-S模型对非线性互联系统进行模糊建模,在此基础上,给出模糊分散观测器的H_∞设计和基于观测器的模型参考跟踪分散模糊控制的设计.应用李亚普诺夫和线性矩阵不等式方法给出了模糊分散系统稳定的充分条件.仿真结果进一步验证了所提出的模糊分散控制方法的有效性.     

基于状态观测器的混沌动态系统跟踪控制

针对一类连续混沌动态系统,提出一种基于状态观测器的跟踪控制方法来进行混沌控制.在引入状态观测器观测混沌动力学系统状态变量的基础上,采用反馈线性化方法将非线性混沌系统转换为线性系统,再针对反馈线性化后的线性系统设计轨迹跟踪控制器,实现被控混沌系统的跟踪控制.仿真结果进一步验证了该方法的有效性.     

GPS Spoofing Attack Detection in Smart Grids Based on Improved CapsNet

This paper analyzes the influence of the global positionong system(GPS)spoofing attack(GSA)on phasor measurement units(PMU)measurements.We propose a detection method based on improved Capsule Neural Network(CapsNet)to handle this attack.In the improved CapsNet,the gated recurrent unit(GRU)is added to the front of the full connection layer of the CapsNet.The improved CapsNet trains and updates the network parameters according to the historical measurements of the smart grid.The detection method uses different structures to extract the temporal and spatial features of the measurements simultaneously,which can accurately distinguish the attacked data from the normal data,to improve the detection accuracy.Finally,simulation experiments are carried out on IEEE 14-,IEEE 118-bus systems.The experimental results show that compared with other detection methods,our method is proved to be more efficient.     

Vibration reduction of seat suspension using observer based terminal sliding mode control with acceleration data fusion

In this work, a disturbance observer and state observer based terminal sliding mode (TSM) controller with acceleration data fusion is proposed for the active control of a seat suspension. In practical applications, the driver's body and the friction forces are difficult to be accurately described with a mathematical model; for this reason, the proposed controller is designed based on a model simplified from a 6-degree-of-freedom (6-DOF) seat-driver model with nonlinear friction. The disturbance observer and state observer are designed together with Linear Matrix Inequality (LMI) method. For improving the observer's performance, a complementary filter is applied to fuse the estimation of the seat suspension velocity from the acceleration measurement and the state observer. The proposed controller is validated using simulations with various bump excitations applied, and the conventional state feedback TSM controller is implemented for comparison. The proposed controller is also implemented in a practical active seat suspension prototype, and a well-tuned commercial heavy duty vehicle seat suspension is applied for comparison. The power spectral density (PSD) value and ISO 2631–1 standard are used to evaluate the active seat suspension system's performance under random vibration. Both the simulation and the experimental results indicate that with the proposed controller, the vibration magnitude caused by a rough road can be greatly reduced, and the driver ride comfort is greatly improved.     

Nonfragile Observer for Discrete-Time Switched Nonlinear Systems with Time Delay

This paper investigates the problem of the nonfragile observer design for discrete-time switched nonlinear systems with time delay. Based on the average dwell-time approach and linear matrix inequality (LMI) techniques, an exponential stability criterion for the discrete-time switched delay system with Lipschitz nonlinearity is derived. Based on several technical lemmas, the discrete-time observer design can be transferred to the problem of solving a set of LMIs. Furthermore, in cases when the gain of the state observer varies, a kind of nonfragile observer is proposed, and the solution to the observer gain is also obtained by solving a set of LMIs. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.     

基于电力调控数据挖掘的混合IDS研究

为适应大数据背景,提出一种基于电力调控数据挖掘的混合IDS自动构建方法。该系统利用公共路径挖掘算法,将同步相量测量数据和调控日志相融合,自动学习各类场景,并将系统状态遍历匹配到公共路径做出分类决策。为验证该方法,搭建了一个包含25个场景的试验平台,并对三母线两馈线系统进行训练和评估,其中90.2%的场景被正确分类。结果表明该IDS具有较高检测精度,可适用于电力调控要求的任务环境。