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有源电力滤波器在电能质量控制中的应用 总被引:15,自引:12,他引:15
有源电力滤波器是治理谐波,改善电能质量的有效措施。本文对有源电力滤波器的工作原理,及其不同接线方式的特点和适用范围进行了综述。比较了几种有源电力滤波器以及无源滤波器的组合方案,分析了各自的优缺点。最后,对有源电力滤波器的应用前门进行了展望。 相似文献
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基于单周控制的三相四线制有源电力滤波器 总被引:42,自引:12,他引:42
该文提出一种单周控制的三相四线制有源电力滤波器,它不需要检测三相负载电流和三相输入电压,不需要繁琐的无功电流和谐波电流计算,也不需要任何乘法器。控制器结构简单,整个控制器由几个带复位积分器,比较器,触发器和一些线性元件组成。具有控制精度高,补偿效果好的特点,滤波器工作于恒定开关频率,易于工业应用,在建立数学模型的基础上,进行了仿真研究,仿真结果证明其有很好的动静态补偿性能,能有效地补偿系统谐波、零序和无功电流,提高输电线功率因数和传输效率。 相似文献
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无差拍控制在串联电力有源滤波器中的应用 总被引:31,自引:3,他引:28
利用状态空间矢量描述三相电压量电流量,建立了串联电力有源滤波器的状态方程,并通过设计状态反馈环节使系统的闭环极点配置在原点处,以及前馈环节的误差补偿来褫无差拍控制。根据综合后系统的状态方程和当前的状态信息推算出下要产周期的开关控制量,并在下一开关周期驱动开关管,最终使输出电压跟踪参考电压。仿真结果验证控制算法的可行性。 相似文献
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一种适用于三相四线制配电系统非对称的有源电力滤波器 总被引:1,自引:0,他引:1
在配电系统中,由于非线性负荷的广泛使用,因此产生了大量的高次谐波电流,造成电力系统电压畸变,使电力元件损耗增加,给电力系统的运行带来很大危害.高次谐波的存在,已被认为是污染电力系统的公害. 相似文献
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One of the most emphasized problems to be solved in power systems in recent years is the line‐current harmonics problem. This is due to the use of diode rectifiers, PWM converters, nonlinear loads, and so on. To reduce or eliminate such current harmonics, an active power filter (APF), which is a sophisticated power electronic converter, has been studied and used in some practical applications. In this paper, we propose and discuss two new control methods for three‐phase shunt APFs: the sinusoidal line‐current control method and the instantaneous‐reactive‐power compensation control method. They are based on pulsewidth prediction control, or a predictive‐instantaneous‐current PWM control. Neither any instantaneous power information nor coordinate transformation is necessary for control. In the sinusoidal line‐current control scheme, the controller governs the switching devices of the APF by using the pulse width that is optimally predetermined at the beginning of every switching period with the sinusoidal current reference. The line currents flow sinusoidally and are in phase with the voltage accordingly. In the instantaneous‐reactive‐power compensation control, the control is performed so that the resultant circuit of the load and the APF is regarded as a time‐variant conductance circuit model. The APF with this control scheme can cancel effectively the instantaneous reactive component produced by the load though the controller is simple. This paper discusses the performance characteristics of the APFs when a three‐phase diode rectifier and an unbalanced load are connected to the line. The practicability of the proposed methods is verified by experiment. © 1999 Scripta Technica, Electr Eng Jpn, 130(3): 68–76, 2000 相似文献
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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
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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
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A new PWM technique for the current-fed PWM converter is proposed. As the control variables, the instantaneous active and reactive powers are used instead of the line current. They are proportional to the instantaneous active and reactive current vector. The switching state of the PWM converter is given by the selection method of the appropriate current vector among the seven kinds of the current vectors with the zero current vector. The active current is controlled by the zero current vector and the reactive current depends on the kind of selected current vector. These variables basically are controlled by PWM switching from two kinds of hysteresis comparator. In addition to this, the compensation of the filter circuit can be obtained automatically by the PWM control based on the active and reactive current detected from the source current. In this paper, the principle of the PWM technique for the current-source PWM converter is proposed. Then, some simulation results are shown. After that, the feasibility of the system is verified by experimental results. 相似文献
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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
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Shinya Matsunami Naoki Yamamura Yuzuru Tsunehiro 《Electrical Engineering in Japan》1996,116(4):109-119
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
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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
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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
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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