【作者】 陈仲；

【导师】 徐德鸿；

【作者基本信息】 浙江大学 ， 电力电子与电力传动， 2005， 博士

【摘要】 有源电力滤波器对于电能质量的调整和控制将是未来最重要的的先进手段之一,而其中,并联型有源电力滤波器过去和将来都将占据最主流的地位。目前国内有源电力滤波器市场正渴求具有自主知识产权和核心技术,并且价格合理的实际产品。本文针对最基础、最实用并且最利于产业化的并联有源电力滤波器进行了较为系统和深入的理论与应用研究,为其实用化奠定了较好的基础。 在运用并联有源电力滤波器对非线性负载进行补偿时,首先需要明确补偿策略,以便有目的和针对性地进行控制和补偿。文中首先基于瞬时无功功率理论,研究了三相系统中两种主要的补偿控制策略,即网侧恒功率补偿策略和网侧正弦电流补偿策略。阐述了各自的机理,选择依据和补偿目标。文中总结了当前主流的谐波检测方法,提出了一种用于谐波和无功准确检测的改进同步坐标系法。 本文在建立并联有源电力滤波器数学模型(包括三相三线、电容中点式和四桥臂式三种拓扑)的基础上,采用电流分解方法研究APF的直流侧电容电压波动和被补偿电流的谐波分布的关系。并且通过估算出的直流侧电容容量与电容电压纹波的关系,将为直流侧电容值的优化设计提供了依据。 并联有源电力滤波器主电路的设计是核心环节之一。文中通过对采用滞环电流控制的电容中点式有源电力滤波器的工作过程研究和分析,揭示了各参数之间的相互关联和制约关系。通过α-β两维平面上的矢量模型和矢量图形分析方法,基于对电流跟踪误差矢量的度量,推导出滤波器直流侧电容电压的临界值的表达式。此外,文中还分析了电感值选取原则和取值范围。 实时、高精度的谐波检测和控制是有源滤波器的重要部分。本文提出了一种基于DSP基波提取的混合型谐波检测改进方案设计,设计了系统DSP主程序软件,并解决了实际运行中易受到的抗干扰问题。本文在改进设计方案基础上,提出了在基于同步参考坐标系的谐波检测算法中引入基波相位补偿的策略,以克服时延,实现无延迟基波分量提取;此外本文提出了基于低速率采样设计策略对算法中对检测性能至关重要的数字低通滤波器的设计进行了优化。 在前几章的设计和分析基础上,建立了一台基于DSP控制的并联有源电力滤波器实验样机,并进行了相关的实验研究。为了保证系统稳定运行,对于直流侧电压闭环控制以及均压闭环控制分别进行了建模和分析,设计了相关的调节器;并精心设计了一套软启动方案。此外,针对实际应用问题之一,即整流电路交流侧电流所具有的高特征参数:如:谐波畸变率(THD)、电流峰值以及电流变化率(di/dt)等,本文探讨了采用负载交流侧串接阻抗来提高有源滤波性能的方法,相对于混合型滤波方案,成本低且可操作性强。 通过研究和实验证明,本文所研究、提出的关于并联有源电力滤波器补偿策更多还原

【Abstract】 Active power filter (APF) is one of the most important approaches to control power quality based on advanced power electronic. The shunt active power filter plays the most leading role in the past or future. Domestic filtering market is thirsting for the practical products which have our own knowledge property, core technique and reasonable price. This paper do systemic and deep research on the most fundamental and applied shunt active power filter, including related theoretics and application issues.Compensating strategy should be confirmed when using active filter for nonlinear loads. Two main compensating strategy, including constant source power strategy and sinusoidal source current strategy are studied. Their characteristic, Selection principle and compensation objective is described. The dominant harmonic detecting method is summarized in this paper and a modified technique based on synchronous reference is proposed for accurate harmonic and reactive current detection.The mathematic model of shunt active power filter, including three-leg 3-wire, capacitor midpoint four-wire and four-pole fur-wire topology, are established. Using decomposition of current, the relation between the voltage ripple of dc side capacitor and the characteristic of compensating current are revealed. Moreover, the optimization of dc side capacitance can be done by virtue of the above relation.Main circuit design is one of the core tache in the systematic design. The operation of capacitor midpoint four-wire shunt active filter adopting hysteresis control is studied and analyzed to reveal the relation of main parameters of APF. The main parameters of APF are associated with and are conditional upon each other. Through vector model in 2-phase α-β reference frame and vector graphical aid design method, the critical value of dc bus voltage will be derived. Besides, the selection of ac side inductor is also been discussed.Real-time and accurate harmonic detection and control is the key for practical active filter implementation. An improved design scheme based on fundamental component extraction using DSP is presented in this paper. Phase-compensation strategy of fundamental component, as well as optimal digital low pass filter based on low sampling rate are introduced into harmonic detection algorithm based on synchronous reference frame for delayless harmonic detection with high accuracy.A shunt active power filter prototype based on DSP has been set up in our lab forexperimental study. The dc side voltage of APF and its balance should be well controlled for its practical use. Both the closed loop of dc side voltage and its balancing loop are modeled and analyzed. An applied soft-startup scheme is also been introduced. To improve the compensating performance for rectifier circuit, whose input current often characterized by high THD, crest value and di/dt, the method of series connecting impedance in the ac side of load is investigated. This measure is more simple and practical than hybrid solutions.Through the research and experimental results, it can be verified that the key techniques for APF described in this paper, including control strategy, main circuit design, harmonic detection and application solutions, etc, is viable and effective.更多还原