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1.
预测瞬时值控制电力用三相有源滤波器   总被引:1,自引:0,他引:1  
本论文提出三相并联型有源滤波器的两种新的控制方法,即正弦波化控制和瞬时无功功率的控制方法,它们是基于预测瞬时电流的PWM控制。利用这种控制方法,既不需要瞬时功率信息,也不需要坐标变换,能够实现电流的正弦波化并能有效地消除由负载产生的瞬时无功分量,通过这种控制能有效地简化控制电路。  相似文献   

2.
In this paper, the use of a three‐level inverter as a shunt active power filter is carried out, taking advantage of the benefits of multi‐level inverter, namely, the reduction both in the overall switching losses and in total harmonic distortion. The main focus of this article is to investigate the potentialities of the inverter employed as shunt active power filter on the compensation of the reactive power and the mitigation of harmonics drawn from a nonlinear load and unbalanced sources. The most previously reported three‐level inverter‐based shunt active power filters have been controlled and monitored through conventional controllers, which require a complicated mathematical model. In order to overcome this problem, an extended intelligent controller is proposed for a three‐level shunt active power filter. The aim of the proposed fuzzy logic control algorithm is to improve the behavior of voltage across the floating capacitors in steady/dynamic states and to minimize the switches commutations by taking into account the references of the harmonic currents injected in the network. The proposed control strategy has been simulated, and the obtained results prove that it is very successful. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

3.
An effective system control method is presented for applying a three‐phase current‐source PWM converter with a deadbeat controller to active power filters (APFs). In the shunt‐type configuration, the APF is controlled such that the current drawn by the APF from the utility is equal to the current harmonics and reactive current required for the load. To attain the time‐optimal response of the APF supply current, a two‐dimensional deadbeat control scheme is applied to APF current control. Furthermore, in order to cancel both the delay in the two‐dimensional deadbeat control scheme and the delay in DSP control strategy, an Adaptive Line Enhancer (ALE) is introduced in order to predict the desired value three sampling periods ahead. ALE has another function of bringing robustness to the deadbeat control system. Due to the ALE, settling time is made short in a transient state. On the other hand, total harmonic distortion (THD) of source currents can be minimized compared to the case where ideal identification of the controlled system can be made. The experimental results obtained from the DSP‐based APF are also reported. The compensating ability of this APF is very high in accuracy and responsiveness although the modulation frequency is rather low. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(1): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20014  相似文献   

4.
给出了基于谐波电流零逼近的有源电力滤波器新型控制策略。采用检测电源电流的控制方式,构成了闭环控制系统。利用瞬时无功理论计算出电源谐波电流,并直接进行滞环比较,以控制主电路开关器件的通断,从而使电源谐波电流逼近于零,达到谐波抑制的效果。仿真结果表明,该方法可准确跟踪负载谐波电流,使电源电流趋于正弦,原理清晰,控制简单,可实现动态补偿。  相似文献   

5.
Many researchers have attempted to clarify the definitions of active power, reactive power, active current, reactive current, etc. for unbalanced and nonsinusoidal three‐phase situations. The so‐called pq theory has given a new definition of instantaneous reactive power, and it has been discussed and developed by many authors. In this paper, the merits and demerits of the instantaneous reactive power compensator are discussed. It is shown theoretically that applying instantaneous reactive power compensation to unbalanced three‐phase systems has a serious disadvantage in that it causes third‐order harmonic currents on the source side, which problem cannot be avoided. To overcome this problem the authors propose a new approach, and name it the “quasi‐instantaneous” reactive power compensator. It compensates individual‐phase reactive currents. The basic principles of the quasi‐instantaneous reactive current compensator are discussed in detail, and its validity is confirmed using digital simulation. In particular the authors show that the power factor of each phase becomes unity on the source side, but the source currents remain unbalanced when the proposed method is applied. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(3): 73–81, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.1162  相似文献   

6.
有源电力滤波器任意次谐波电流检测的新算法   总被引:16,自引:0,他引:16  
有源电力滤波器是一种消除电力系统谐波污染的重要装置,随着电力电子技术的发展,它的使用也越来越广泛。针对有源电力滤波器的特点,基于瞬时无功功率理论,提出一种对于任意指定次数的谐波电流的检测算法。该算法能够克服数字式控制器延迟时间对于谐波补偿的影响,可实现谐波的实时补偿。理论分析和仿真结果证实了所提方法的正确性。  相似文献   

7.
有源电力滤波器相电流互感器容错控制   总被引:2,自引:1,他引:1       下载免费PDF全文
为了实现有源电力滤波器(APF)在交流侧电流互感器故障状态下的可靠运行,提出一种基于相电流重构的交流侧电流互感器容错控制策略。通过分析相电流重构应用在滞环SVPWM控制中的不足,提出在相电流重构中设计状态观测器。构建有源电力滤波器的电流闭环观测模型,用观测出的电流值来对存在缺失的重构电流进行修正,解决了相电流重构技术运用在滞环SVPWM控制中重构电流不完全的问题,实现了APF系统的带故障运行。在Matlab/Simulink中进行仿真验证,并在实验样机中进行实验,结果均证明了该容错策略的正确性和可行性。  相似文献   

8.
有源滤波器电流控制新方法   总被引:4,自引:2,他引:2  
本文提出了一种基于最优电压空间矢量的有源滤波器滞环电流控制方法。该方法的特点是以相间电流误差而非相电流误差作为控制对象,因此可用三个滞环比较器构成参考电压矢量所在区别判别器,在此基础上应用最优电压矢量实行滞环电流控制。在同样的控制精度下,该方法可有效地降低开关频率,减小有源滤波器开关损耗。计算机仿真结果验证了这一方法的有效性。  相似文献   

9.
并联有源滤波器的最优电压滞环电流控制   总被引:10,自引:4,他引:10  
简要介绍了并联有源滤波器的原理其普通滞环电流控制的特点,针对普通滞环电流控制方法的不足,提出并详细分析了一种最优电压滞环电流控制新方法,该方法的显著特点是通过识别参考电压矢量知电流误差矢量的区域控制滤波器的输出,避免了复杂计算和逆变器不必要的开关,并且快速,准确,从而改善了有源滤波器的性能。  相似文献   

10.
叙述了有源电力滤波器APF(Active Power Filter)的基本原理,分别介绍了组成APF的谐波和无功电流检测电路、补偿电流发生电路的构成和功能,在此基础上,介绍了常用的APF的谐波和无功电流检测方法、补偿电流控制方法和直流侧电压控制方法。为了验证APF的补偿功能同时加深对其控制方法的认识和理解,用Matlab 6.5/Simulink下的SimPower Systems Blockset对整个三相并联电压型APF系统进行了仿真研究。仿真结果表明,电压空间矢量脉宽调制SVPWM(Space VectorPulse Width Modulation)控制的APF能对负载电流中的谐波和无功分量进行快速精确的补偿。  相似文献   

11.
针对三相电压型PWM整流器和有源电力滤波器具有相同的拓扑结构,提出了一种预测直接功率控制(P-DPC)策略。以整流器交流侧输出电压为控制对象,使整流器不仅能够为负载提供能量,并兼具有源电力滤波器抑制电网谐波的功能,提高了设备的利用率。该控制策略与空间矢量脉宽调制相结合,与传统直接功率控制相比,不使用开关表和锁相环且开关频率固定,算法更为简单。李雅普诺夫稳定性分析证明了控制算法能够使系统全局渐进稳定。最后通过仿真验证了所提出的控制策略的正确性和可行性,仿真结果表明控制系统具有良好的动态性能和鲁棒性。  相似文献   

12.
基于电压空间矢量分析原理,提出一种适用于并联型有源电力滤波器的电流控制方法。揭示了参考电流优化跟踪策略,该策略能保证在单个开关周期内,使误差电流矢量的幅值以最快的速度逼近于零,从而实现参考电流的快速跟踪。基于参考电流优化跟踪策略,在充分考虑逆变器的实际电压输出能力的情况下,对逆变器输出电压矢量进行精确计算,并通过在单位开关周期内输出多个基本电压矢量的方法合成该矢量,以保证误差电流微分矢量同时具有最优方向和最大幅值,从而在快速跟踪指令电流的同时,不会造成逆变器不可控,提高控制系统的快速性和可靠性。实验结果验证了所提方法的有效性。  相似文献   

13.
基于瞬时无功理论的并联型有源滤波器恒功率控制   总被引:1,自引:0,他引:1  
根据瞬时功率理论,研究了并联型有源滤波器的工作机制,通过实现逆变器有功功率和无功功率的解耦,提出了并联型有源滤波器恒功率控制策略。该控制策略通过分离出待补偿的功率分量,然后计算出其与逆变器实际功率的误差,根据误差生成逆变器参考电压,采用空间矢量调制算法对功率进出补偿,实现系统的恒功率控制。该策略可以有效抑制系统交流侧谐波电流,补偿无功功率,稳定输出的有功功率,改善系统稳态性能。最后,通过Maflab/Simulink对该控制策略进行仿真验证,结果证明了该策略的正确性和有效性。  相似文献   

14.
Inductance has a particularly important role in power circuits. The authors have proposed the Variable Active–Passive Reactance (VAPAR), which can produce a virtual variable inductance. In this paper, the transient power characteristics of a balanced three‐phase variable inductance are analyzed using the instantaneous active and reactive power theorem. With an ideal voltage source or an ideal current source connected to a balanced three‐phase variable inductance, the transient power characteristics are analyzed theoretically, and then the results are verified through simulations. In the other cases, it is difficult to solve for the transient power, but it is shown that the transient power characteristics can easily be estimated from the results of simulations in which an ideal voltage source or an ideal current source is connected to a balanced three‐phase variable inductance. Experiments are also carried out to verify the theoretical analysis and simulations. © 2001 Scripta Technica, Electr Eng Jpn, 136(2): 49–57, 2001  相似文献   

15.
有源电力滤波器(active power filter,APF)是一种动态抑制谐波和无功的电力电子装置,以并联型有源电力滤波器为研究对象,从APF补偿电流的控制和直流侧电容电压角度出发,分析了电源电流控制方式,实现补偿电流的检测及双闭环反馈控制,提高系统的补偿精确度和动态响应性能。另外,直流侧电压的指令值都是根据电网电压的工作范围、APF的直流侧电容、额定输出电流、PWM逆变器输出侧电感、电流电压调节器以及调制策略等参数设计的,在考虑直流侧电压与APF功率损耗和补偿性能关系的基础上,提出了采用下垂调节器设计逆变器直流侧电压的控制参考值,使其兼顾APF的功率损耗及补偿性能综合平衡的优点。仿真结果验证了该APF控制系统的正确性和有效性。  相似文献   

16.
为了使电网电压尽可能接近正弦波形,提出了一种通过校正网侧电压波形来减小电网中的谐波电流的智能控制有源滤波技术.智能芯片检测电网电压波形,再与标准正弦电压波形比较求得误差电压,该误差电压中含有电网中谐波电流的波形信息.用这个误差电压形成PWM整流器的指示电流,有源滤波器在智能芯片的控制下从电网吸收谐波电流并向电网输出基波...  相似文献   

17.
An active filter (AF) is a device to eliminate switches. There are two types of AF, the voltage source type and the current source type. The voltage source type is common in practical use today. But we have studied and already reported that the AF of the current-source type has the characteristics of rapid and precise controllability of the output current and little interference between the AF and the distribution line. In this paper, we propose two schemes to improve its performance and to reduce its capacitance. To improve the performance of AF, we changed the PWM carrier from the triangular wave used in a previous paper to the sawtooth wave. However, the switching rates remain the same. By using the 5 [kHz] sawtooth carrier (corresponding to 2.5 [kHz] triangular wave) and the multiplexed connection of AF, harmonic currents of less than 19-th order can be eliminated in the distribution line. To reduce the capacitance of the AF, we proposed an AF which eliminates only harmonic currents. By using other apparatus for fundamental reactive power compensation, a more economical system can be achieved. The experimental results on the tested apparatus show that these methods are useful for realization of a current-source type AF.  相似文献   

18.
根据配电网10kV高压侧对大容量谐波抑制与无功补偿的要求,提出注入式混合型有源电力滤波器拓扑结构(IHAPF),详细阐述了IHAPF的谐波抑制特性.同时结合某铜箔厂大型整流装置谐波抑制和无功补偿的工程实例,介绍了IHAPF的设计方法和软硬件构成,并从项目成本和治理效果两方面分析了IHAPF的应用优势.  相似文献   

19.
根据目前常见的几种混合有源滤波器,提出一种注入式混合有源滤波器,使有源滤波器不再承受基波电压,最大限度地减少了有源滤波器的容量。阐述混合有源滤波器和注入式有源滤波器的工作原理,通过样机实验验证结论正确性。  相似文献   

20.
针对电网中非线性负载引起的谐波问题,提出了一种并联混合有源电力滤波器结构。基于此拓扑结构,建立了其数学模型,并设计了基于PI控制策略的电流控制器。针对传统PI控制方法补偿精度受带宽制约,补偿效果不理想的问题,提出了基于重复控制的电流双闭环控制方法,并设计了双闭环电流控制器。仿真和实验结果表明,该控制策略具有很高的稳态补偿精度,能够有效补偿由非线性负载引起的谐波电流。补偿后电网电流THD降低到5%以下,波形近似于正弦波。  相似文献   

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