A novel active power filter for reactive power compensation and harmonic suppression

A new single-phase active power filter for reactive power compensation and harmonic suppression is proposed. Besides the general performance of other active power filters, it also has the feature that it can maintain the mains current as a sine-wave and correct the displacement power factor close to unity even when the mains voltage is distorted. A prototype of this active power filter is developed and tested under rectifier load to verify its performance. The test results show that the proposed scheme can compensate the reactive power and suppress harmonics of the nonlinear load effectively.     

A control algorithm for three-phase three-wired active powerfilters under nonideal mains voltages

In this paper, a control algorithm for the performance improvement of three-phase three-wired active power filters under nonideal mains voltages is proposed and analyzed. It begins with an analysis of an instantaneous reactive power algorithm that was previously applied to the three-phase active power filter design. In that design, the circuit performance was found unsatisfactory under nonideal test scenarios. Our proposed design was, therefore, motivated in order to solve such problems. In the proposed scheme, not only was the control circuit simplified, but it also served as a potential candidate for the performance improvement of active filter design. The proposed algorithm has been implemented as a prototype. Results of experimental verification under various scenarios are presented     

A new UPS scheme provides harmonic suppression and input powerfactor correction

A new parallel processing uninterruptible power supply (UPS) configuration is proposed in this paper. It provides active power line conditioning to minimize mains current distortion. This performance is superior to a conventional UPS. A prototype has been implemented and tested to verify its performance. The experimental results show that the input power factor of the proposed UPS is nearly unity, and the total harmonic distortion (THD) of the input current under nonlinear loading is only 3.618% for a mains voltage with THD of 1.633%     

基于瞬时无功功率理论的APF的研究与仿真

本文介绍了并联型有源电力滤波器的工作原理和基于瞬时无功功率理论的谐波和无功电流检测方法,用Matlab SimUlink建立了带典型负载的电力有源滤波器的仿真模型,模拟实际系统,用于检验其策略和参数在实际条件下的工作情况。仿真模型的结果表明：基于瞬时无功功率理论的有源滤波器,可以很好的起到动态抑制电网谐波和补偿无功的作...     

New hybrid active power filter for harmonic current suppression and reactive power compensation

In the case of undistorted and balanced grid voltages, low ratio shunt active power filters (APFs) can give unity power factors and achieve current harmonic cancellation. However, this is not possible when source voltages are distorted and unbalanced. In this study, the cost-effective hybrid active power filter (HAPF) topology for satisfying the requirements of harmonic current suppression and non-active power compensation for industry is presented. An effective strategy is developed to observe the effect of the placement of power capacitors and LC filters with the shunt APF. A new method for alleviating the negative effects of a nonideal grid voltage is proposed that uses a self-tuning filter algorithm with instantaneous reactive power theory. The real-time control of the studied system was achieved with a field-programmable gate array (FPGA) architecture, which was developed using the OPAL-RT system. The performance result of the proposed HAPF system is tested and presented under nonideal supply voltage conditions.     

Unified constant-frequency integration control of active powerfilters-steady-state and dynamics

An active power filter (APF) is a device that is connected in parallel to and cancels the reactive and harmonic currents from a group of nonlinear loads so that the resulting total current drawn from the AC mains is sinusoidal. This paper presents a unified constant-frequency integration (UCI) APF control method based on one-cycle control. This method employs an integrator with reset as its core component to control the pulse width of an AC-DC converter so that its current draw is precisely opposite to the reactive and harmonic current draw of the nonlinear loads. In contrast to previously proposed methods, there is no need to generate a current reference for the control of the converter current, thus no need for a multiplier and no need to sense the AC line voltage, the APF current, or the nonlinear load current. Only one AC current sensor is used to sense the AC main current and one DC voltage sensor is used to sense the DC capacitor voltage. The control method features constant switching frequency operation, minimum reactive and harmonic current generation, and simple analog circuitry. It provides a low cost and high performance solution for power quality control. Steady-state and dynamic study is presented in this paper. Design example is given using a two-level AC-DC boost topology. A prototype was developed to demonstrate the performance of the proposed APF. This control method is generalized to control a family of converters that are suitable for APF applications. All findings are supported by experiments and simulation     

选择性有源滤波器治理12脉波整流器的谐波

文章介绍12脉波整流器应用选择性有源滤波器抑制谐波电流和补偿无功,采用基于瞬时功率理论的谐波和无功电流检测方法。对有源滤波器和负荷系统进行仿真,并对仿真结果进行详细分析。仿真结果表明：基于瞬时功率理论的谐波和无功电流检测方法可以准确、实时地检测出三相电流中的任意次谐波及无功电流,有源滤波器抑制11次和13次谐波电流,并补偿无功。     

两种电铁谐波及无功电流检测方法的研究与仿真

针对电气化铁道供电系统对谐波及无功电流检测的要求,介绍了两种检测方法,并分别给出了检测原理图。前者是基于鉴相原理的瞬时谐波电流检测法,后者是基于瞬时无功功率理论的谐波分离法,对该方法基于不同截止频率时的LPF进行了分析比较。理论分析和仿真结果证明两种方法都能实时地检测出电铁供电系统中的瞬时谐波及无功电流,前者算法和实现更为简单。稳态运行的仿真波形证实了文中所提方法的有效性。     

一种单相串联混合电力有源滤波器的研究

文中对串联混合电力滤波器抑制谐波的原理进行了分析。为了检测单项系统的谐波电流,提出一种基于虚拟三相法和瞬时无功理论的谐波检测方法,并且对串联滤波逆变器的直流侧电压的控制进行了讨论。仿真结果证明了其有效性。     

新型三相三线制并联有源滤波器的滑模控制方法

为了提高有源滤波器的谐波补偿效果,设计了一种新型滑模控制器,用于三相三线制并联有源滤波器的参考电流跟踪控制.谐波电流检测方法采用基于瞬时无功功率理论的谐波电流检测方法,能快速、准确的检测出负载电流中的谐波分量.直流侧电压控制方法采用PI控制方法实现.Simulink仿真结果显示,与传统的滞环比较控制方法相比,所设计的新型滑模控制方法能够有效的降低跟踪误差,提高有源滤波器的谐波补偿效果.     

Using AC-fed PWM converters as instantaneous reactive powercompensators

A general control method that fully utilizes the inherent capability of AC-fed PWM converters to compensate for reactive and harmonic currents adsorbed by other loads is presented. For this purpose, suitable definitions of instantaneous active and reactive current and power terms are introduced. Optimum modulation laws are then derived according to a general control theory valid for PWM multiconverter systems which also results in maximum system efficiency. Simulated results demonstrate the capabilities of the proposed compensation method, which can also be implemented in existing systems as only modifications of the control section are needed     

A fuzzy-controlled active front-end rectifier with current harmonicfiltering characteristics and minimum sensing variables

A control strategy which allows conventional voltage-source current-controlled (VSCC) pulsewidth modulation (PWM) rectifiers to work simultaneously as active power filters is presented. The proposed control strategy also allows compensating the system power factor and compensating unbalanced loads. The measurement and/or calculation of the harmonics and reactive power are not required, making the proposed control scheme very simple. The active front-end rectifier acts directly on the mains line currents, forcing them to be sinusoidal and in phase with the mains voltage supply. To improve the dynamic of the system, the amplitude of the current is controlled by a fuzzy system, which adjusts the DC-link voltage of the PWM rectifier. The strategy is based on connecting all the polluting loads between the PWM rectifier and their input current sensors. The main advantages of this approach are the following: (1) there is no need to install a specially dedicated active power filter; (2) it also works simultaneously as a power factor compensator; and (3) no special and complicated calculations are required for harmonic elimination. The viability of the proposed active front-end rectifier is proved by simulation and with experimental results obtained from a 2 kVA PWM prototype     

A novel active power filter based on the least compensation currentcontrol method

A new least compensation current technique to detect the harmonic and reactive current for active power filters is presented in this paper. With the technique, a novel active power filter based on the least compensated current control is proposed, in which the measurement of harmonic and reactive current and the generation of compensated current are completed in the same closed-loop. Compared with the existing control methods of active power filter, the proposed method has simpler structure, quicker dynamic, higher reliability and better compensation performance. Simulating and experimental results are provided that verified theoretical predictions and demonstrate the effectiveness of the proposed control method and circuit configuration     

APF中数字低通滤波器的设计及仿真实现

文中介绍了基于瞬时无功功率理论的ip-iq谐波检测方法及对低通滤波器的要求,分析了数字低通滤波器的类型、阶数及截止频率对有源电力滤波器谐波检测效果的影响。利用MATLAB仿真软件设计了二阶巴特沃思（Butter—worth）数字低通滤波器,对ip-iq谐波检测算法进行了仿真研究,仿真结果证明所选择的数字低通滤波器的正确性。     

基于瞬时无功功率理论的谐波和无功电流检测

介绍了基于瞬时无功功率的谐波和无功电流实时检测理论。该理论突破了传统的平均值功率定义,系统的定义了瞬时无功功率、瞬时有功功率。可实时的检测电力系统中的谐波和无功电流。讨论了瞬时无功功率理论,得出基于瞬时无功功率理论的谐波和无功电流检测算法。结果表明,这种检测法能为抑制谐波和无功补偿提供可靠的谐波及无功分量。     

Harmonic and reactive power compensation based on the generalizedinstantaneous reactive power theory for three-phase four-wire systems

This paper presents harmonic and reactive power compensation based on a generalized theory of instantaneous reactive power for three-phase power systems. This new theory gives a generalized definition of instantaneous reactive power, which is valid for sinusoidal or nonsinusoidal and balanced or unbalanced three-phase power systems with or without zero-sequence currents and/or voltages. The properties and physical meanings of the newly defined instantaneous reactive power are discussed in detail. A harmonic and reactive power compensator based on the new theory for a three-phase harmonic-distorted power system with zero-sequence components in the load current and/or source voltage is then used as an example to show harmonic and reactive power measurement and compensation using the new theory. Simulation and experimental results are presented     

An instantaneous reactive volt-ampere compensator and harmonicsuppressor system

A novel control method for a reactive volt-ampere compensator and harmonic suppressor system is proposed. It operates without sensing the reactive volt-ampere demand and nonlinearities present in the load. The compensation process is instantaneous, which is achieved without employing any complicated and involved control logic. The compensator is operated in cycle-by-cycle reference-current-controlled mode to achieve the instantaneous compensating feature. A mathematical model of the scheme is developed. Detailed analysis and simulation results are presented. A laboratory prototype of the compensator is developed to validate the results     

有源电力滤波器新型控制策略

基于瞬时无功功率理论和预测控制算法，提出了一种新型有源电力滤波器控制方法，该方法消除了电源电流在负载电流发生突变处产生的锯齿抖动。实时检测负载电流的二阶导数，判断负载电流是否发生突变。发生突变则采用预测控制程序模块进行补偿电流控制。这种方法可以应用在单相、三相电力系统的滤波电路中。仿真结果证明了这种算法的有效性。     

一种基于瞬时无功功率的改进谐波电流检测算法

为满足有源电力滤波器谐波电流检测的高精度、高实时性的要求,文章给出一种对瞬时无功功率的改进方法。这种方法减少了计算量,使得实时性、可实现性增强,可以直接应用于三相三线制,三相四线制以及单相系统的谐波和基波无功电流的检测。并综合考虑FIR滤波器和IIR滤波器的优缺点,使用均值滤波器和Butterworth滤波器的串联滤波方法。计算机仿真表明该改进方法具有检测精度高,响应速度快,易于实现的特点。     

A series active power filter based on a sinusoidalcurrent-controlled voltage-source inverter

A series active power filter working as a sinusoidal current source, in-phase with the mains voltage, has been developed and tested. The amplitude of the fundamental current in the series filter is controlled through the error signal generated between the load voltage and a pre-established reference. The control allows an effective correction of power factor, harmonic distortion and load voltage regulation. Compared with previous methods of control developed for series active filters, this method is simpler to implement because it is only required to generate a sinusoidal current, in-phase with the mains voltage, the amplitude of which is controlled through the error in the load voltage. The proposed system has been studied analytically and tested using computer simulations and experiments. In the experiments, it has been verified that the filter keeps the line current almost sinusoidal and in-phase with the line voltage supply. It also responds very quickly under sudden changes in load conditions, reaching its steady-state in about two cycles of the fundamental