混沌算法下电力滤波器定频滞环电流控制

针对传统电力滤波器定频滞环电流控制时受谐波影响较大,存在电流控制误差较大、电流补偿效果较差等问题,提出基于混沌算法的电力滤波器定频滞环电流控制.通过建立电力滤波器数学模型,利用有源滤波器中谐波检测电路,根据基尔霍夫电流一般定律,提取电力滤波器工作特征;分析混沌算法的基本原理,利用Logistic映射获取混沌序列粒子的参数取值,完成负载电流波动轨迹的追踪;通过单相定频方法,固定开关相位与标准脉冲信号相位差,考虑误差电流变化的补偿量,实现电力滤波器定频滞环电流控制.仿真测试结果表明,与传统方法相比,采用所提方法控制电力滤波器定频滞环电流的误差较小,补偿效果以及开关频率控制效果较好.     

基于自适应逆控制的有源滤波器的检测算法

提出一种新的并联型电力有源滤波器的检测方法,通过控制有源滤波器直流电容电压来确定电网电流所需的基波有功分量的幅值,首次将自适应逆控制用于电力有源滤波器.将系统的主电路部分及有源滤波器看作广义有源滤波器,通过自适应逆控制方式控制直流电容电压,使其输出跟随参考输入,最终达到抑制谐波和补偿无功的目的.此检测算法简单有效,稳态和暂态的仿真结果均证实了该算法的可行性.     

基于PSIM的并联型有源电力滤波器的仿真研究

并联型有源电力滤波器能够补偿非线性负载产生的谐波电流、抑制电网电流谐波含量,提高电网的电能质量。文中提出了并联型有源电力滤波器PAPF(Parallel active power filters)新型控制方案,通过仿真验证了分析的正确性。     

一种新型有源电力滤波器电流控制策略研究

针对现有有源电力滤波器结构较为复杂、谐波电流跟踪困难等问题,提出了一种新型有源电力滤波器电流控制策略。该控制策略不需要进行负载电流测量与谐波检测,而是直接在电网侧提取电网电流,并将比例积分与矢量比例积分控制器结合使用以对电网电流进行控制,从而实现谐波补偿。仿真结果证明了该策略的正确性与有效性。     

基于DSP的并联型有源电力滤波器的研制

所研制的有源电力滤波器采用以IGBT为内核的智能功率模块(简称IPM)构成三相全桥逆变主电路,控制电路的核心是32位定点DSP芯片,检测电路由电压和电流传感器主要构成。通过检测电路检测到非线性负载的谐波信号,经由DSP运算转换并发出PWM的脉冲信号,控制逆变器产生符合要求的补偿电流到电网。     

基于神经网络的单相有源滤波器

有源滤渡器的控制是一个典型的非线性控制过程．非常适合用神经网络来实现．本文提出了一种应用于有源滤波器系统的神经网络控制器,神经网络控制器的输入是负载电流和补偿电流。输出是开关控制信号甩于控制有源滤波器产生补偿电流来抵消非线性负载的畸变电流。基于MATLAB/SIMULINK平台．建立了单相有源滤波器仿真模型．仿真结果表明所提出的神经网络控制器的有效性。     

并联型有源电力滤波器的无源性控制

将无源性控制应用于并联型有源电力滤波器,对有源电力滤波器电路进行简化等效．把负载电压和电源电流作为状态变量,把补偿电流作为控制变量,通过坐标变换建立有源电力滤波器的数学模型,通过无源性理论获得简单而容易实现的控制律．仿真结果表明系统具有良好的稳定性和鲁棒性。     

三相三线APF补偿电流的模糊反馈检测与控制

补偿电流的检测是三相有源电力滤波器的关键问题,快速准确地检测出补偿电流并实施有效的控制直接影响到有源电力滤波器的补偿效果.对三相三线制有源电力滤渡器进行电路模型分析,采用T-S模糊反馈控制的方法,获得三相三线制有源电力滤波器的补偿电流,并对电源电流进行实时的模糊反馈控制.采用并行分布补偿的方法设计了模糊反馈控制器,将有源电力滤波器的非线性问题线性化,在稳定性条件下求解线性矩阵不等式,得到无功功率及谐波电流全补偿控制策略的状态反馈增益,由此获得连续的即时补偿跟踪电流,仿真及实验结果验证了补偿电流检测的准确性及模糊反馈控制的有效性,对简化有源滤波器的电流检测与其构成组件具有较大应用价值.     

智能控制有源电力滤波器系统研究

采用新的有源无功补偿与滤波器原理方案,通过信号采集电路采集电网信息,然后通过高性能的TMS320F2812智能控制系统对电力系统信号进行检测、数据处理及计算,得到有关高次谐波的信息,产生控制信号到IPM驱动电路中,控制有源滤波器组对电网中的无功电力与谐波进行补偿,达到预定的效果。并对电网的实时监测、对滤波器监控与电网动态信息实时在LCD上显示出来。此系统在理论仿真与实际电网电力系统无功电力与谐波补偿中取得了良好实验的效果。     

一种新型的并联型单相有源电力滤波器

通过分析并联型有源电力滤波器的工作原理和系统结构,本文提出一种新型的电流闭环预测控制策略,相比于传统的PI控制、滞环控制和预测控制算法,该预测策略能减小计算量,并降低模型的复杂度。同时,谐波电流检测电路采用单相电流延迟60°构造三相电流d-q变换法,获取逆变主电路的参考电流。该滤波系统还引入PI外环以稳定直流侧的电容电压。最后,采用S imu link的电力系统分析模块进行仿真。结果表明,该滤波系统可有效检测高次谐波分量,迅速补偿谐波电流,同理论分析一致。     

Robust Data Hiding in Audio Using Allpass Filters

A novel technique is proposed for data hiding in digital audio that exploits the low sensitivity of the human auditory system to phase distortion. Inaudible but controlled phase changes are introduced in the host audio using a set of allpass filters (APFs) with distinct parameters of allpass filters, i.e., pole-zero locations. The APF parameters are chosen to encode the embedding information. During the detection phase, the power spectrum of the audio data is estimated in the z-plane away from the unit circle. The power spectrum is used to estimate APF pole locations, for information decoding. Experimental results show that the proposed data hiding scheme can effectively withstand standard data manipulation attacks. Moreover, the proposed scheme is shown to embed 5-8 times more data than the existing audio data hiding schemes while providing comparable perceptual performance and robustness     

有源电力滤波器切换跟踪与优化控制

为了提高有源电力滤波器的动态性能, 基于切换系统理论研究其电流跟踪控制问题. 首先, 建立系统的切换动态模型, 根据切换系统理论和空间电压矢量法证明二次稳定性, 并设计相应的切换控制序列. 考虑到控制器的数字化实现, 建立系统的离散切换系统模型, 提出在采样周期内使系统性能最优的切换控制策略. 仿真结果表明, 该控制策略能实现对指令电流的精确跟踪, 降低功率器件的开关频率, 从而有效地提高系统的动态性能.

     

Local path planning using a new artificial potential function composition and its analytical design guidelines

This paper presents a new framework for path planning based on artificial potential functions (APFs). In this scheme, the APFs for path planning have a multiplicative and additive composition between APFs for goal destination and APFs for obstacle avoidance, unlike conventional composition where the APF for obstacle avoidance is added to the APF for goal destination. In particular, this paper presents a set of analytical guidelines for designing potential functions to avoid local minima for a number of representative scenarios based on the proposed framework for path planning. Specifically the following cases are addressed: (i) a non-reachable goal problem (a case in which the potential of the goal is overwhelmed by the potential of an obstacle), (ii) an obstacle collision problem (a case in which the potential of the obstacle is overwhelmed by the potential of the goal) and (iii) a narrow passage problem (a case in which the potential of the goal is overwhelmed by the potential of two obstacles). The example results for each case show that the proposed scheme can effectively construct a path-planning system with the capability of reaching a goal and avoiding obstacles despite possible local minima.     

基于滑模控制的三相四线制电力有源滤波器

建立了采用四桥臂逆变器为主电路的三相四线制电力有源滤波器的数学模型。该电力有源滤波器基于滑模的控制策略,采用指数趋近律的方法以减少抖动的影响。Matlab仿真结果表明,基于滑模控制策略的三相四线制电力有源滤波器具有很好的谐波抑制性能。     

A multi-objective approach to optimal placement and sizing of multiple active power filters using a music-inspired algorithm

This paper proposes a new multi-objective framework for optimal placement and sizing of the active power filters (APFs) with satisfactory and acceptable standard levels. total harmonic distortion (THD) of voltage, harmonic transmission line loss (HTLL), motor load loss function (MLLF), and total APFs currents are the four objectives considered in the optimization, while harmonic distortions within standard level, and maximum allowable APF size, are modeled as constraints. The proposed model is one of non-convex optimization problem having a non-linear, mixed-integer nature. Since, a new modified harmony search algorithm (MHSA) is used and followed by a min–max technique in order to obtain the final optimal solution. The harmony search algorithm is a recently developed optimization algorithm, which imitates the music improvisation process. In this process, the Harmonists improvise their instrument pitches searching for the perfect state of harmony. The newly developed method has been applied on the IEEE 18-bus test system and IEEE 30-bus test system by different scenarios and cases to demonstrate the feasibility and effectiveness of the proposed method. The detailed results of the case studies are presented and thoroughly analyzed. The obtained results illustrate the sufficiency and profitableness of the newly developed method in the placement and sizing of the multiple active power filters, when compared with other methods.     

基于强跟踪滤波器的开关变换器故障诊断

Buck变换器又称降压变换器、串联开关稳压电源、三端开关型降压稳压器。广泛用于计算机、家用电器、控制系统和通信系统中的电源几乎都是开关电源,具有超快速负载动态响应、高功率变换效率、高功率密度、低电压、大电流的特性.开关变换器作为它的主要电路,故障率较高,对它故障诊断研究是有意义的。基于强跟踪滤波理论,给出了一种开关变换器电路故障实时诊断的一种方法。该方法以建立一种开关变换器电路状态空间模型为基础,利用强跟踪滤波器对电路状态及元件参数进行估计,当元件参数发生软、硬型故障时,根据强跟踪滤波器对元件参数的跟踪结果及修正的Bayes分类算法,可实时诊断开关变换器电路中的元件故障。仿真结果证明了该方法的有效性。     

一种新型的串联型有源电力滤波器

为了消除基波磁通补偿(FMFC)有源电力滤波器(APF)的控制延时,提高APF的电流跟踪性能,提出了采用基于预测电流补偿的新方法.建立了基于预测电流控制的基波磁通补偿有源滤波器的数学模型,采用离散化的方法预测下一周期参考电流值,实现APF电流的预测控制.这种控制方法可以消除采样、计算等带来的延时,具有开关频率固定、电压利用率高、开关损耗小、动态响应快等优点.最后,在此基础上搭建了实验平台,仿真与实验结果证明了将预测电流控制方法应用于基波磁通补偿有源滤波器的有效性和可行性.     

Path planners based on the wave expansion neural network

In the potential field approach to path planning, the development of the artificial potential field (APF) is a computationally intensive operation. The realization that the APFs can be developed by parallel distributed techniques has prompted interest in using neural networks for developing APFs. This paper describes a neural network called the wave expansion neural network (WENN) and shows that it is capable of developing a variety of APFs that are useful for path planning. The discretized environment including information about the target configuration (position and orientations) and the obstacles are applied to the WENN as input. Activity is then propagated in the form of waves throughout the WENN neural field and at equilibrium, the resulting neural activity distribution forms the desired APF. We analyze the computational complexity of the WENN based APF generation and compare it with conventional development of APFs. We also describe different path planners which use these APFs to plan paths for moving objects with two and three degrees of freedom.     

注入式有源电力滤波器直流侧电压的剖析

针对现在有源电力滤波器应用要求,提出了一种新型的注入式混合有源电力滤波器拓扑结构,这种新型有源电力滤波器能补偿一定的无功,注入电路采用基波谐振的方法大大降低了有源滤波器的容量,使其适用于高压系统中。在分析系统的滤波原理的基础上建立了系统的数学模型。在考虑系统参数的选择上．分析了系统的动态过程,建立了电网电压与有源滤波器直流侧电压微分方程的关系。通过仿真实验验证了系统模型与参数选择的有效性。