一种基于PID+线性多变量反馈的同步发电机励磁控制器

介绍了一种用于同步发电机的新型励磁控制方法———PID 线性多变量反馈控制策略。该控制方法的思路是将PID的输出和线性多变量反馈励磁控制器的输出进行综合,从而设计出一种新型的同步发电机励磁控制器。仿真与实验结果均表明该励磁控制器在提高电力系统的稳定性以及稳定发电机输出电压方面有明显效果。     

非脆弱参数不确定系统二次稳定性研究

基于线性系统二次稳定性理论,针对一类具有参数不确定性线性系统,研究了加性控制器增益摄动的非脆弱二次稳定性问题.证明了具有加性控制器增益摄动的闭环系统二次稳定的充分必要条件,采用线性状态反馈控制方法,将非脆弱控制器求解过程转化为标准H∞状态反馈设计问题.并推导给出了参数不确定系统的基于线性矩阵不等式和彤Riccati方程两种非脆弱性控制器的求解方法.     

一类控制方向未知的不确定非线性系统的输出调节

针对控制方向未知的情况下,具有线性外部系统的不确定非线性系统的全局鲁棒输出调节问题,假设系统和高频增益符号是未知的,并且未知的参数可以是任意大,这就为控制器的设计带来了挑战.为了解决这个问题,首先,进行坐标变换,计算出新的状态方程;然后,通过使用Nussbaum动态增益技术、自适应控制方法和内模原理,将鲁棒输出调节问题转化为鲁棒稳定性问题,并设计一种动态输出反馈控制器;最后,通过所设计动态输出反馈控制器使得Lyapunov的导数负定,这样就从理论上解决了非线性输出反馈系统的全局鲁棒输出调节问题.通过实例说明了所提自适应控制器的有效性.     

一类MIMO系统的输出通道任意幅值/相角裕度调节方法

针对一类有限维多输入多输出线性时不变系统,提出了一种新的调节输出通道幅值/相角裕度的方法。该方法采用离散线性二次调节器理论设计静态通用采样保持函数控制器,可同时在系统所有反馈控制回路的输出通道实现任意大的幅值裕度和直到90°的相角裕度,且控制器形式简单、易于实现。仿真结果表明了该方法的有效性。     

一种改进型重复控制器的研究

提出一种新的改进型重复控制策略,克服了传统重复控制器内模使用过多数据存储空间的缺点.详细分析新型控制器的模型,给出控制器优化设计方法.在设计中加入电流内环,通过电感电流反馈来降低输出滤波器的谐振峰值,增加系统的稳定性,简化了重复控制器的设计.与传统直接重复控制器相比,去除了North滤波器,弥补了North滤波器谷点设计不精确的缺点.     

逆变器重复控制器设计与仿真

针对实际应用给出了重复控制器内模、补偿器以及周期延迟环节的优化设计方法,推导出了重复控制器的稳定性判断条件和收敛指数。基于3 kVA逆变器硬件和控制参数设计了重复控制器,给出了重复控制器各关键参数的设计过程,并进一步基于重复控制器稳定性判断条件对设计结果进行了稳定性验证。利用Matlab软件对设计结果进行了验证,仿真结果表明在逆变器控制中添加重复控制器后,能明显降低逆变器带非线性负载时输出电压的总谐波失真度值。     

时滞依赖型区间时滞系统非脆弱H_∞控制

针对一类状态和控制输入矩阵均为区间矩阵的不确定时滞系统,其中状态和控制输入同时具有未知但有上界的时间滞后,基于Lyapunov稳定性理论,利用线性矩阵不等式(LMI)方法,讨论了该类时滞系统的时滞依赖型非脆弱H∞状态反馈控制器设计问题.在区间不确定性和控制器执行机构扰动均满足增益有界条件下,得到了该类时滞系统的满足H∞性能的一个充分条件.通过求解一个线性矩阵不等式(LMIs)组,即可获得鲁棒H∞控制器.最后对某型飞机作机动飞行仿真,仿真结果表明该鲁棒控制器设计方法是有效的.     

三相恒压恒频逆变电源的输出波形重复控制技术

对瞬时控制和重复控制的内模原理进行了分析，提出了基波扰动瞬时反馈控制内模与谐波重复控制内模相结合的控制器。仿真和实验验证了该方案可以保证系统有较快的动态响应，稳压精度高，输出电压谐波畸变率小。     

基于切换原理的非均匀采样系统输出反馈控制

在非均匀采样系统中,存在着刷新时间间隔不确定和时变的情况,这给系统控制器的设计造成了很大困难.针对此问题,本文将刷新时间间隔看作时延变量,将不同时延的系统动态变化过程转化为不同子系统的动态变化过程,从而将时延的变化转化为不同子模型之间的切换,最终将非均匀采样系统描述为一类具有有限个子系统的离散时间切换系统.利用输出反馈控制方法,基于平均驻留时间条件,使输出反馈闭环非均匀采样系统指数稳定.最后,通过一个非均匀采样系统仿真实例证明了提出方法的有效性.     

基于状态反馈控制的倒立摆系统分析和设计

针对多输入多输出的倒立摆系统平衡控制,利用牛顿一欧拉方法建立了直线型一级倒立摆系统的数学模型.在分析的基础上,采用状态反馈控制中极点配置法设计了用于直线型一级倒立摆系统的控制器.通过采用MATLAB仿真及其对实际系统的调试验证,表明了该控制器的设计是合理的.     

Zero-phase odd-harmonic repetitive controller for a single-phase PWM inverter

In this paper, a zero-phase odd-harmonic repetitive control scheme is proposed for pulse-width modulation inverters. The proposed repetitive controller combines an odd-harmonic periodic generator with a noncasual zero-phase compensation filter. It occupies less data memory than a conventional repetitive controller does. Moreover, it offers faster convergence of the tracking error, and yields very low total harmonics distortion (THD) and low tracking error. Analysis and design of the proposed system are presented. Experimental results with the proposed repetitive controller are presented to validate the approach. The phenomena of even-harmonic residues in the proposed control system is discussed and experimentally demonstrated.     

重复控制在IGBT逆变电源中的应用

为了有效解决由非线性负载和死区等因素引起的输出波形畸变问题,提高稳态控制精度,研究并实现了基于重复控制算法的单相逆变电源。研究工作主要集中在建立单相逆变电源的数学模型和状态方程;分析重复控制器的基础理论和稳定性,详细讨论周期延时环节、超前环节、补偿环节的陷波器、二阶低通滤波器等各组成部分的设计方案,总结出工程实用的重复控制器设计步骤;利用MATLAB/Simulink进行建模和仿真分析;对控制系统的核心算法使用基于模型的设计方法,直接生成C代码;最终在3KVA的单相IGBT逆变电源实验样机上进行算法验证。实验结果表明该方案的有效性和可行性。     

Design of discrete-time repetitive control system for poleplacement and application

A new repetitive control system is proposed from the viewpoint of pole placement. First, the proposed repetitive controller can assign all poles of the closed-loop system on a disk with a given radius and the center at the origin. As a result, faster convergence of the controlled error to zero than the previous ones is obtained. Next, the proposed controller is obtained explicitly, and the design method does not require an equation to be solved. The design effort is independent of the period of the repetitive signals to be tracked or rejected. In other words, the design effort is very small, even if the period is very large. Then, the robustness of the control system is improved by introducing a low-pass finite-duration impulse-response filter in the controller. Finally, the proposed scheme is applied to a DC servomotor system, and the effectiveness is demonstrated by both simulations and experiments     

High-performance programmable AC power source with low harmonicdistortion using DSP-based repetitive control technique

This paper proposes a new control scheme based on a two-layer control structure to improve both the transient and steady-state responses of a closed-loop regulated pulse-width-modulated (PWM) inverter for high-quality sinusoidal AC voltage regulation. The proposed two-layer controller consists of a tracking controller and a repetitive controller. Pole assignment with state feedback has been employed in designing the tracking controller for transient response improvement, and a repetitive control scheme was developed in synthesizing the repetitive controller for steady-state response improvement. A design procedure is given for synthesizing the repetitive controller for PWM inverters to minimize periodic errors induced by rectifier-type nonlinear loads. The proposed control scheme has been realized using a single-chip digital signal processor (DSP) TMS320C14 from Texas Instruments. A 2-kVA PWM inverter has been constructed to verify the proposed control scheme. Total harmonic distortion (THD) below 1.4% for a 60-Hz output voltage under a bridge-rectifier RC load with a current crest factor of 3 has been obtained. Simulation and experimental results show that the DSP-based fully digital-controlled PWM inverter can achieve both good dynamic response and low harmonics distortion     

Digital repetitive learning controller for three-phase CVCF PWMinverter

In this paper, a plug-in digital repetitive leaning control scheme is proposed for three-phase constant-voltage constant-frequency (CVCF) pulsewidth modulation inverters to achieve high-quality sinusoidal output voltages. In the proposed control scheme, the repetitive controller (RC) is plugged into the stable one-sampling-ahead-preview-controlled three-phase CVCF inverter system using only two voltage sensors. The RC is designed to eliminate periodic disturbance and/or track periodic reference signal with zero tracking error, The design theory of plug-in repetitive learning controller is described systematically and the stability analysis or overall system is discussed. The merits of the controlled systems include features of minimized total harmonic distortion, robustness to parameter uncertainties, fast response, and fewer sensors. Simulation and experimental results are provided to illustrate the effectiveness of the proposed scheme     

Linear Phase Lead Compensation Repetitive Control of a CVCF PWM Inverter

This paper presents a simple and efficient linear phase lead compensation repetitive control scheme for engineers to develop high-performance power converter systems. The linear phase lead compensation helps a repetitive controller to achieve faster convergence rate, higher tracking accuracy, and wider stability region. In the proposed scheme, the phase lead compensation repetitive controller is plugged into generic state-feedback-controlled converter systems. Its comprehensive synthesis, which involves principle, analysis, design, modeling, implementation, and experiments, is systematically and completely presented in great detail. A complete series of experiments is successfully carried out to verify the solution.     

Adaptive repetitive control of PWM inverters for very low THDAC-voltage regulation with unknown loads

An adaptive repetitive control scheme is proposed and applied to the control of a pulsewidth-modulated (PWM) inverter used in a high-performance AC power supply. The proposed control scheme can adaptively eliminate periodic distortions caused by unknown periodic load disturbances in an AC power supply. The proposed adaptive repetitive controller consists of a voltage regulator using state feedback control, a repetitive controller with tuning parameters and an adaptive controller with a recursive least-squares estimator (LSE). This adaptive repetitive controller designed for AC voltage regulation has been realized using a single-chip digital signal processor (DSP) TMS320C14 from Texas Instruments. Experimental verification has been carried out on a 2 kVA PWM inverter. Simulation and experimental results show that the DSP-based adaptive repetitive controller can achieve both good dynamic response and low total harmonic distortion (THD) under large-load disturbances and uncertainties     

Adaptive repetitive control to track variable periodic signals with fixed sampling rate

Recent research has shown that the repetitive control is very efficient in tracking periodic signals, where it is required that an integer number of samples in each period. However, in some industrial applications where the signal period varies but other requirements force a fixed sample rate, the number of samples per period may be a non-integer. To address this problem, this paper presents a new adaptive repetitive control, which deals with the non-integer samples per period due to the fixed sampling rate. The proposed adaptive repetitive control consists of two portions, the repetitive controller and nominal controller, where the former uses a fictitious sampler operating at a variable sample rate maintained at multiple times of the signal frequency, while the latter uses a fixed sampling rate. Interpolations are utilized to generate the fictitious samples required for the repetitive learning. The nearly perfect tracking was achieved for non-integer samples per period, when a simple linear interpolation is used. The error due to the interpolation is quantified, which is negligible to the residual tracking error. The comparison of the proposed and the existing schemes shows the significant improvement on the tracking performance. The experimental results on the control of a servomotor demonstrate the effectiveness of the proposed schemes.     

基于神经网络的CMP过程智能R2R预测控制

针对化学机械研磨(CMP)过程非线性、时变和不易在线测量的特性,提出了基于径向基函数(RBF)神经网络和微粒群(PSO)算法的CMP过程run-to-run(R2R)预测控制器NNPR2R。首先通过样本数据用减聚类算法和最小二乘法构建CMP过程的RBF神经网络预测模型,解决了复杂CMP过程难以建立精确数学模型的难题和提高了预测模型的精度。然后通过PSO算法滚动优化求取控制律,解决了基于导数的优化技术易于陷入局部最优的问题并提高了控制精度。仿真结果表明,CMP过程NNPR2R控制器的性能优于常规的EWMA方法,有效抑制了过程漂移和减小了不同批次间产品的差异,显著降低了材料去除率(MRR)的均方根误差。