基于DSP的有源电力滤波器控制器

分析了有源电力滤波器(APF)的工作原理,设计了其控制器.采用基于瞬时无功功率理论的d-q检测法得到APF的谐波指令电流.由于传统滞环控制其滞环宽度是固定的,则开关器件的频率不固定.本文采用定频滞环电流控制方法,该方法实现简单、精度较高且响应速度快,同时受负载参数变化的影响较小,鲁棒性好;相比较于其它常用的脉冲宽度调制技术,本文脉冲信号的产生采用具有算法简单、适用于数字实现、开关损耗小以及硬件电路简单等特点的空间矢量方法.最后给出了基于DSP的有源电力滤波器控制器的实现过程,并给出了采用此控制器的APF的部分实验结果.     

单相有源滤波器测控装置的设计

介绍了单相有源滤波器(APF)的检测和控制系统.主要介绍了硬件电路的结构和软件流程,采用鉴相法实现了对谐波和无功的检测,用滞环控制方法控制开关动作,对CAN通信在整个系统中的应用也做了阐述.实验结果表明,用DSP28335作为核心处理器对有源滤波器控制满足了实时性好和精确性高的要求,滤波效果良好.     

基于自抗扰控制器的有源滤波器直接电流控制

为提高有源电力滤波器的控制策略水平,本文分析了电压型有源电力滤波器、电源及非线性负载三者之间的有功功率平衡,在此基础上提出了一种基于自抗扰控制器的有源电力滤波器的直接电流控制方法.将负载电流和电源电压等因素作为系统的未知干扰,用扩张状态观测器对未知扰动进行观测,然后利用非线性反馈控制律进行补偿.无需检测谐波电流及无功电流,省去了复杂计算,简化了控制器的设计.仿真结果显示:电网电流被补偿为与电网电压同相位的正弦波,证实了该控制方法是可行的.     

预测瞬时值控制电力用三相有源滤波器

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。     

Fuzzy logic controller for three-level shunt active filter compensating harmonics and reactive power

In this paper, the three-level inverter is used as a shunt active power filter, making use of the multilevel inverter advantages of low harmonic distortion, and reduced switching losses. This PWM inverter is employed as shunt APF compensating reactive power and suppresses harmonics drawn from a nonlinear load. Most previously reported three-phase active power filters are based on two-level inverters with conventional controllers requiring a complex and a complicated mathematical model. In order to overcome this problem a fuzzy logic controller applied and extended to a three level shunt APF is proposed.     

基于DSP的混合有源电力滤波系统数字控制器的设计

对并联混合型有源电力滤波系统的构成和工作原理作了分析研究,它是由小容量有源滤波器通过变压器和无源滤波器串联构成的,并与被补偿的谐波负载并联连接。基于。TMS320F240 DSP的开发套件,采用脉宽调制(PWM)定时器下溢中断工作方式,设计了数字控制器主程序和中断服务子程序。设计的一套实验系统用来消除谐波负载产生的谐波影响。实验结果表明,有源电力滤波器投入后,电网谐波电流得到了有效的抑制。     

Modeling and controller synthesis for the cascaded H-bridge multilevel active power filter with ADALINE-based identifiers

This paper presents the averaged state-space modeling and controller synthesis methodology for the cascaded H-bridge multilevel active power filters (CHB-APFs). The accurate harmonic current compensation and dc-link stabilization among the individual H-bridge modules are crucial problems for the CHB-APF, which is the prerequisite for the global stability of the system. In this study, a novel voltage balancing algorithm is devised by splitting the dc-link control task into two parts, namely, the average voltage control and the voltage balancing control, where the sine and cosine functions of the phase angle of the fundamental grid voltage are used, respectively. To ensure accurate phase tracking, a novel phase-locked loop algorithm is proposed by using the adaptive linear neural network (ADALINE). Moreover, a separate ADALINE identifier is applied for reference current generation, and the proportional-resonant controller is used for current tracking. The simulation results obtained from the Alternative Transient Program (ATP/EMTP) are provided under dynamic reactive power compensation and active filtering scenarios. The experimental results from the prototype system are also presented, which verifies the effectiveness of the devised algorithms.     

High-power active filter using LC-tuned filter

Usually, to eliminate the harmonics of transmission lines, LC tuned filters are employed to bypass these harmonic components. However, the elimination ability is limited by its damping resistance. Therefore, active filters composed of high-frequency PWM converters are desirable. In comparison with the LC tuned filters, the cost would be very high even in high-power systems. In this paper, a low-cost and high-power active filters for a dc transmission system is proposed. It has active filter ability as well as low cost for high-power uses. Its main circuit is composed of conventional LC filters in series with square-wave voltage inverters. The voltage of the inverter is controlled to cancel the voltage drop of the internal resistance of the LC filter. Thus the Q-factor of the filter can appear at infinity. Calculation of the harmonic and the control are done by DSP (TMS 32010). In the experimental system and simulations, two three-phase tuned filters, 5th and 7th, are employed. Excellent results under 1 percent distortion voltage are obtained.     

Comparisons between a hybrid shunt active filter and a pure shunt active filter

This paper deals with the hybrid shunt active filter for harmonic compensation of a three‐phase diode rectifier in a 480‐V adjustable‐speed motor drive system. The hybrid filter is formed by a three‐phase LC filter tuned around the seventh harmonic frequency and a small‐rated three‐phase voltage‐source PWM inverter. The LC filter and PWM inverter are directly connected in series. As a result, the DC capacitor voltage of the PWM inverter in the hybrid filter is much lower than that of a conventional pure shunt active filter. This results in higher efficiency, less switching ripple, and less EMI emission. Computer simulation is carried out to compare the hybrid filter with the pure filter in terms of circuit configuration and filtering performance. Simulation results indicate that the hybrid filter is superior in effectiveness and viability to the pure filter. In addition, theoretical analysis based on vector loci confirms the validity of the simulation results. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(2): 61–70, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20145     

A fuzzy-logic-based controller for active rectifier

This paper presents a current-sensorless active rectifier specifically designed for low-cost applications. Both the control and the modulation use fuzzy logic. A simple model of the system is given in order to explain the current feedforward control using fuzzy logic and the fuzzy-logic-based modulation, then, the new algorithm is analyzed looking for high performance even using small passive elements and low switching frequency. Performance are compared with those of a closed-loop proportional-plus-integral (PI)-based rectifier with space-vector modulation (SVM). This comparison has been carried out either considering the whole systems or a combination of their components (PI control + fuzzy modulation or fuzzy feedforward control + SVM). The results show that even without current sensors, the low-frequency distortion of the line currents and the DC voltage oscillations produced by the proposed system are very limited, ensuring performance similar to those of PI-based closed loop active rectifiers.     

有源滤波器中数字低通滤波器设计及其实现

本文介绍了数字滤波器的种类和设计方法,在MATLAB环境下对满足有源滤波器性能要求的低通数字式滤波器进行了实例设计,并分析了其滤波特性,最后结合有源滤波器中所使用的DSP控制器,完成了该低通数字滤波器的实现。     

A three‐phase,active power filter with a predictive‐instantaneous‐current PWM controller

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     

Butterworth有源抗混叠滤波器设计

信号混叠是视频采样系统中的一种失真。为了防止这种失真,本文设计了一个4阶的视频有源低通抗混叠滤波器。通过对二阶Bessel、Butterworth和Chebyshev等多种滤波器的性能分析比较,本文采用Butterworth滤波器来设计该抗混叠滤波器,电路的拓扑结构采用Sallen-Key结构,并采用高速双运算放大器(SN10502),以构造一个可放入狭小印刷电路板中的4阶Butterworth滤波器。测量结果表明,该滤波器在视频频段内几乎不出现峰值、平坦度好,并且阻带抑制效果好。微分增益和相位同样也很不错。最后,还讨论了在设计视频有源滤波过程中应该如何根据实际应用选择运算放大器,如何选择电容、电阻值,如何布局布线以及如何消除振荡。     

An electronically tunable RC active filter

An RC active filter with embedded FET switches is presented for the realization of a general second order filter. The filter consists of minimal number of capacitors, two differential input dual output operational amplifiers, fixed resistors and resistors connected as potential dividers. The network has low Q and ω₀ sensitivities; further, the finite bandwidth of the operational amplifiers has negligible effect on the Q of the filter. The introduction of FET switches in the network results in frequency scaling and consequently, the possibility of electronically tuning it. In addition, by switching the FETs by pulses of very low duty cycle, it is possible to obtain subaudio filters using resistive and capacitive components of smaller values than required for a conventional filter. Experimental results pertaining to the band-pass case are also included.     

并联有源电力滤波器交流侧输出滤波器设计

针对输出滤波器存在的放大网侧电流畸变率、阻尼电阻发热严重的问题,提出一种工程化有源电力滤波器交流侧输出滤波器参数设计方法.采用二阶高通滤波器作为有源电力滤波器输出滤波器拓扑,在综合考虑输出滤波器的开关纹波滤波效果与电流畸变率、电容无功容量、电阻功耗之间关系的基础上,结合理论分析、仿真、实验研究,设计总结了并联有源电力滤波器输出滤波器的参数选择方法.采用该方法为50kVA并联有源电力滤波器设计了一套输出滤波器.实验结果表明:加装输出滤波器后,电流纹波抑制到滤波前的1/4以下,网侧电流畸变率增大约1个点,滤波电阻上90%以上的工频电流被旁路,电阻发热得到有效控制,实验结果验证了该输出滤波器设计方法的有效性.     

混合有源滤波器的复合控制研究

分析了注入式混合有源滤波器的工作原理,它可以降低有源部分的基波分压,减少有源部分容量,更适用于高压系统,还可以有效地克服了开关器件容量和成本等因素的影响.提出了一种通过检测电网电流和负载谐波电流的复合控制方案.通过控制上述两个量来防止系统阻抗间可能的串并联谐振,而达到抑制电网谐波的目的.     

Power active filter for controlled three-phase rectifier

Contents This paper presents a power active filter with inductive storage that permits a very good compensation of the higher current harmonics generated in the mains by a controlled or uncontrolled three-phase rectifier.

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Aktives Leistungsfilter für einen gesteuerten Stromrichter

Übersicht In der Arbeit wird ein aktives Leistungsfilter mit induktivem Speicher beschrieben, das eine bessere Kompensation der von einem gesteuertem Stromrichter erzeugten Stromharmonischen erlaubt.

     

电力有源滤波器的技术现状

采用现代电力电子技术、数字信号处理技术和先进控制理论的电力有源滤波器(APF)技术对电网谐波可进行动态实时补偿,是解决谐波污染、改善电能质量最有效和最具潜力的途径.介绍了电力有源滤波器的基本结构和原理,讨论了电力有源滤波器的各种谐波电流检测和补偿电流控制方法.     

并联混合型电力滤波器的仿真研究

并联混合型电力滤波器能够很好地改善无源滤波器的滤波性能,实现在大功率场合下的谐波抑制和无功补偿.通过建立混合系统的单相等效电路图,分析了并联混合型电力滤波器的补偿原理和补偿特性;通过研究主电路拓扑结构,给出了主电路各个组成部分的设计方法,其中包括无源滤波器设计、耦合变压器设计、输出滤波器设计及有源滤波器控制策略设计.文章利用Matlab/Simulink构建了仿真模型,给出了仿真模型中各部分的参数,得到了仿真结果.仿真结果表明这种混合型电力滤波器可有效地改善无源滤波器的滤波性能,证明了设计方法的有效性.     

基波补偿型有源电力滤波器的设计

采用串联基波补偿技术和PWM跟踪控制电路,设计了一款简单、方便、精度高的电力有源滤波器.实验仿真表明:在满足基波磁通补偿条件下,该有源滤波器对负载谐波源具有较好的滤波特性,达到了设计要求.