基于磁通补偿原理的有源电力滤波器

根据电力电子系统的磁通补偿原理。介绍了一种基于磁通补偿原理和并联变压器谐波阻抗控制的有源电力滤波器的设计方案,给出了采用单位功率因数控制策略控制有源电力滤波器的基本结构和谐波电流检测方法。同时通过仿真实验,给出了对滤波器进行补偿的补偿电流和系统电流的波形。     

基于DSP单周控制有源电力滤波器的研究

针对有源电力滤波器中畸变电流检测的快速实时响应问题,研究有源电力滤波器的单周控制原理与控制策略,提出单相并联型有源电力滤波器的单周控制模型。并在以DSP为核心控制器的基础上,设计单周控制有源电力滤波器,对其进行了实验研究,对试验的结果进行了分析。实验结果表明,该法实时性好、控制电路结构简单、动态特性好。     

基于TMS320LF2812的并联型有源电力滤波器的设计与实现

针对谐波抑制和无功补偿的问题,对有源电力滤波器进行一系列研究,阐述了有源电力滤波器的基本原理以及控制策略。基于TMS320LF2812设计了有源电力滤波器,包括DSP控制板、电压采样电路,电流采样电路以及IPM功率单元的设计,并给出了有源电力滤波器的软件设计。最后利用MATLAB仿真软件对所涉及的有源电力滤波器进行仿真,验证了有源滤波器系统的正确性以及谐波补偿电流和滞环比较控制模块的有效性。     

并联型有源电力滤波器直流侧电压柔性控制策略

针对并联型有源电力滤波器的直流侧电压控制特点,提出了一种对直流侧电压进行柔性控制的并联型有源电力滤波器控制策略。该策略中,在直流侧电压控制部分引入反馈低通滤波器,削弱直流侧固有谐波对输出电流控制的影响;在电流控制的输出部分通过增加直流侧电压前馈系数,抵制在变换桥中可能引入的直流侧电压谐波影响。仿真结果表明直流侧电压柔性控制策略能够降低APF系统补偿后的电源电流总谐波畸变率,从而改善并联型有源电力滤波器的谐波补偿性能。     

有源电力滤波器电流控制PI校正研究

采用PI校正方法对并联有源电力滤波器电流环进行控制。通过对并联有源电力滤波器的开环幅频特性分析和PI校正分析,得到了并联有源电力滤波器电流环控制的校正参数。通过仿真实验,对有源电力滤波器的补偿精度进行分析,结果证明该校正方法能够取得较好的补偿效果。     

三相整流桥直流侧和交流侧并联型有源电力滤波器比较研究

三相直流侧和交流侧有源电力滤波器均可用于三相不可控整流桥的谐波治理。从谐波补偿效果、有源滤波器的补偿容量、开关应力三个方面对二者进行了分析和对比。分析结果表明,由于直流侧有源电力滤波器并联在整流桥的直流侧,在换相处的负载电流变化率比交流侧小得多,因此直流侧有源电力滤波器的补偿性能优于交流侧有源电力滤波器。同时由于直流侧有源电力滤波器工作在电压电流两个象限,因此其补偿容量和开关应力远小于交流侧有源电力滤波器。     

有源电力滤波器的建模与仿真研究

介绍了并联型有源电力滤波器的基本原理,采用单位功率因数(UPF)的控制策略,利用Matlab/Simulink中的电力系统仿真工具箱对并联型有源电力滤波器进行建模和仿真研究,得到了仿真结果。仿真结果表明,该方案对电网上面谐波和无功电流的抑制起到很好的效果。     

空间矢量脉宽调制在有源滤波器中的应用

文章针对典型的三相整流电路中产生的谐波对电网产生的影响,研究易于数字化的SVPWM,将其应用于并联有源电力滤波器内层跟踪控制中,给出一种补偿功能较为完善的并联有源电力滤波器及其控制方法。仿真结果表明：SVPWM调制用于并联有源滤波控制可以明显改进补偿的动态性能,提高滤波效果。     

基于电容中分式有源电力滤波器的研究

针对三相四线制系统中谐波和无功功率统一补偿的问题,设计了一种电容中分式并联型有源电力滤波器。采用基于瞬时无功功率理论的方法检测谐波,三维空间矢量(3D-SVPWM)的方法产生补偿电流。通过搭建Matlab/Simulink仿真平台,验证了基于电容中分式三相四线制有源电力滤波器良好的补偿性能。     

并联混合型有源电力滤波器的仿真研究

并联混合型有源电力滤波器能很好地补偿谐波源产生的谐波。文中有源滤波器主电路采用3“H桥”共用一个电容的形式。利用MATLAB中的Simulink模块对并联混合型有源电力滤波器进行建模仿真,并对仿真结果进行分析。     

Three-Level Inverter-Based Shunt Active Power Filter in Three-Phase Three-Wire and Four-Wire Systems

This paper presents a direct current-space-vector control of an active power filter (APF) based on a three-level neutral-point-clamped (NPC) voltage-source inverter. The proposed method indirectly generates the compensation current reference by using an equivalent conductance of the fundamental component using APF's dc-link voltage control. The proposed control can selectively choose harmonic current components by real-time fast Fourier transform to generate the compensation current. The compensation current is represented in a rotating coordinate system with chosen switching states from a switching table implemented in a field-programmable gate array. In addition, a three-phase four-wire APF based on a three-level neutral-point-clamped inverter is also presented. The proposed APF eliminates harmonics in all three phases as well as the neutral current. A three-phase three-wire NPC inverter system can be used as a three-phase four-wire system since the split dc capacitors provide a neutral connection. To regulate and balance the split dc-capacitor voltages, a new control method using a sign cubical hysteresis controller is proposed. The characteristics of the APF system with an LCL-ripple filter are investigated and compared with traditional current control strategies to evaluate the inherent advantages. The simulation and experimental results validated the feasibility of the proposed APF.      

并联型有源滤波器的死区效应及其补偿策略研究

分析了三相四线制有源电力滤波器中逆变器的死区效应对其补偿性能的影响,研究了电流反馈控制和无死区控制两种补偿策略用于上述有源电力滤波器死区补偿的可行性,并通过仿真对两种方法的补偿效果进行比较.结果表明,两者均能有效补偿死区效应的影响;但在实现的难易程度和成本方面,无死区控制策略有一定优势.     

Instantaneous Reactive Power Theory Applied to Active Power Filter Compensation: Different Approaches, Assessment, and Experimental Results

In this paper, the five main formulations of the instantaneous reactive power theory have been chosen to study nonlinear load compensation. They are p-q original theory, d-q transformation, modified or cross-product formulation, p-q-r reference frame, and vectorial theory. The obtention of the compensation current according to each formulation has been established. Next, the behavior of an active power filter (APF) that is implemented with those different control algorithms has been studied. On one hand, a simulation platform with control, APF, and load has been built to test them. Results obtained in an unbalanced and nonsinusoidal three-phase four-wire system have been compared by means of the most adequate indexes. On the other hand, the APF control strategies have been implemented in an experimental platform constituted by a 20-kVA power inverter and a 400-MHz digital signal processing controller board. The final analysis shows that, in general, the five theories present a different behavior, which depends on supply voltage, with respect to distortion. However, all of them widely decrease the waveform distortion. Moreover, a more general compensation objective is possible. It obtains balanced and sinusoidal source current in any conditions of the supply voltage.     

多重化有源电力滤波器的研制

分析了多重化大功率有源电力滤波器的基本结构及控制系统的构成,采用一种基于负载基波电流作为参考电流的控制模式,提出了在该模式下多模块并联时的均流控制方法.应用该方法设计基于DSP和CPLD的数模混合控制系统,给出了采用该系统的二重化有源电力滤波器的实验结果,结果表明,能有效补偿非线性负载产生的谐波,具有很好的补偿效果.     

一种新型混合型有源电力滤波器的研究

提出了一种单相并联混合型有源电力滤波器的电路结构.该电路由有源滤波器与基波串联谐振支路并联再与无源滤波电路串联构成,用于抑制非线性整流负载产生的谐波电流流入电源侧.在该电路中,无源滤波器分担大部分抑制谐波和无功补偿的任务,减少了有源滤波器的容量;有源电力滤波器用于改善无源滤波器的滤波效果,抑制它与系统阻抗可能发生的谐振.实验结果表明,该混合型有源滤波器充分发挥了无源滤波器和有源滤波器各自优点,改善了无源滤波器的滤波性能,同时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,从而使有源电力滤波器可应用于大功率场合.     

基才三相四线APF的模糊直接反馈控制

为解决三相四线有源电力滤波器的非线性控制问题,时三相四线有源电力滤波器进行电路模型分析,提出采用Takagi-Sugeno模糊直接反馈控制的方法,对电源电流进行模糊直接反馈控制,快速地实现了三相四线有源电力滤波器的非线性电流补偿。采用并行分布补偿的方法设计了模糊反馈控制器,将三相四线有源电力滤波器的非线性问题线性化,在稳定性条件下求解得线性矩阵不等式,得到无功功率及非线性电流全补偿控制策略的状态反馈增益．仿真及实验结果验证了此模糊直接反馈控制的有效性。     

A novel shunt hybrid active power filter based on magnetic flux compensation

In this article, the principle of a novel shunt hybrid active power filter (APF) based on magnetic flux compensation is proposed. The parallel transformer can exhibit nearly zero impedance to harmonic current whereas the zero magnetic flux condition is satisfied for harmonics, which leads harmonic current to flow into the transformer branch. Meanwhile, the transformer can exhibit continuously adjustable impedance to the fundamental current based on fundamental magnetic flux compensation, which works together with the passive power filter to compensate for reactive power. A mathematical model is established for system stability analysis and steady state estimation. The experimental results verify that the performance of the proposed APF is satisfactory in harmonic suppression as well as reactive power compensation.     

Research on the filtering characteristic of single phase series hybrid active power filter based on fundamental magnetic flux compensation

In this article, the PWM inverter works as a controlled fundamental current source in the single phase series hybrid active power filter (APF) based on fundamental magnetic flux compensation (FMFC). The series transformer can exhibit the self-impedance of primary winding to harmonic current, which forces harmonic current to flow into passive power filter. With the influence of harmonic current, the voltage of primary winding of transformer is a harmonic voltage, which makes the inverter output currents have a certain harmonic component, and it degrades the filtering characteristics. On the basis of PWM inverter, the mathematical model of series hybrid APF is established, and the filtering characteristics of single phase APF are analysed in detail. Three methods are gained to improve filtering characteristics: reasonably designing the inverter output filter inductance, increasing series transformer ratio and adopting voltage feed-forward control. Experimental results show that the proposed APF has greater validity.     

A Single-Phase DG Generation Unit With Shunt Active Power Filter Capability by Adaptive Neural Filtering

This paper deals with a single-phase distributed generation (DG) system with active power filtering (APF) capability, devised for utility current harmonic compensation. The idea is to integrate the DG unit functions with shunt APF capabilities, because the DG is connected in parallel to the grid. With the proposed approach, control of the DG unit is performed by injecting into the grid a current with the same phase and frequency of the grid voltage and with an amplitude depending on the power available from renewable sources. On the other hand, load harmonic current compensation is performed by injecting into the alternating current system harmonic currents like those of the load but with an opposite phase, thus keeping the line current almost sinusoidal. Both detection of the grid voltage fundamental and computation of the load harmonic compensation current have been performed by two neural adaptive filters with the same structure, one in a configuration ldquonotchrdquo and the other in the complementary configuration ldquoband.rdquo The ldquonotchrdquo filter has been used to compute the compensation current by eliminating only the contribution of the fundamental of the load current, whereas the ldquobandrdquo configuration is able to extract the fundamental of the coupling point voltage. Furthermore, because the active power generation and the APF features require current control of components at different frequencies, respectively, a multiresonant current controller has been adopted. The methodology has been tested successfully both in numerical simulation and experimentally on a suitably devised test setup. The stability analysis of the proposed control approach has been performed in the discrete domain.