谐波情况下的无功补偿设计

本文分析了系统谐波的主要成分,指出了内网谐波和外网谐波对无功补偿的影响,详细讲述了无功补偿串接电抗器和并联谐波滤波器的设计计算方法,尤其是在既有内网谐波又有外网谐波情况下无功补偿滤波器的设计方法。     

基于双反星形整流器负载的TAPF补偿方案研究

针对目前电解电镀等工业应用中快速变化的强非线性负载产生大量谐波和无功的问题,以混合型有源电力滤波器TAPF的谐波与无功补偿技术为背景,基于双反星形整流器负载将传统的阻抗型补偿装置TSC和并联型APF相结合构成TAPF补偿系统。由TSC进行大容量无功补偿,APF进行谐波电流补偿,以使系统具有优良的谐波与无功补偿特性及自适应性,提高了电网电能质量。仿真结果表明,该TAPF补偿方案对工业中应用双反星形整流器负载所引起的一系列与谐波和无功有关的电能质量问题进行了很好的解决。     

广播电视工程中无功补偿与谐波治理分析

广播电视工程中,会产生较大的无功功率的主要为一些负荷量较大的设备,同时使用大量的电子信息产品会有大量的谐波电流产生,从而会严重影响着广电行业的无功补偿装置,并且不利于功率因数的改善,严重则导致无功补偿装置出现致命性破坏。同时,风机、水泵等电动机设备发热或出现抖动等会影响正常工作,若电力仪表测量误差较大的情况下,会造成严重的经济损失,由于大量的谐波电流还可能导致电缆发热、变压器过热等一些安全隐患,甚至造成严重的电气火灾事故等。因此,在电气系统设计中,应尽量抑制谐波对系统造成的严重影响,并对无功率进行补偿。那么,作为一名广电系统的工程师,对于无功补偿和谐波治理的意义和方法应该有深刻的意识。本文研究中,笔者结合自身多年实践经验,深入探讨了广播电视工程中无功补偿与谐波治理的问题,在分析广电行业无功补偿的特点的基础上,对广电系统无功补偿装置的缺陷、谐波对电力系统设备的冲击及危害、广电行业适用的无功补偿装置及无功补偿谐波治理方法进行了阐述,并对无功补偿与谐波治理提出了几点建议,以期能够为广播电视工程中的实践应用提供理论参考。     

补偿电铁谐波及无功电流的有源滤波器的研究

研究应用于补偿电铁谐波及无功电流的单相有源滤波器,基于鉴相原理的谐波及无功电流检测法适合于作为电铁谐渡及无功电流的检测方法,改进的三角波调制电流控制方法能对电铁系统中的谐波及无功电流起到很好的补偿作用.仿真结果表明有源滤波器能够达到综合补偿的目的.     

有源电力滤波器的设计

有源电力滤波器(Active Power Filter)是目前研究比较深入的一种装置,它是一种用于动态补偿,既可抑制谐波,又可以补偿无功的新型电力电子装置,它能对大小和频率都变化的谐波以及变化的无功进行补偿,其应用可克服LC滤波器等传统的谐波抑制和无功补偿方法的缺点。     

关于无功功率补偿和谐波治理在煤矿供电系统中的分析

对煤矿供电系统负荷及系统运行中存在的主要问题进行分析,并对供电电网谐波产生的因素以及对功率因素的影响进行研究,提出了几种无功功率补偿与谐波治理的措施,即装设无功功态补偿装置、无源谐波吸收与静态补偿装置、无功静态补偿电容器等,对这几种无功功率补偿与谐波治理措施的实施效果进行研究。     

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。     

介绍一种实用的电力滤波,补偿装置

电力滤波可消除电网谐波,抑制谐波污染,提高用电质量,电容补偿可消除无功功率,提高功率因数,节约用电。本文着重介绍谐波的危害,如何消除谐波,如何进行无功补偿和提高功率因数等问题;对使用高效实用滤波补偿设备产生的效益进行分析。     

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。     

探析低压配电线路无功补偿装置谐波治理技术

本文在分析谐波污染对低压配电网影响的基础上,对低压配电线路无功补偿装置谐波治理技术进行了分析.     

Solid State Starters, Harmonics and Reactive Compensation: A compromise solution between them in a real case

This paper studies the consequences of having solid state starters with long term ramps in a real pumping case. The harmonic resonances due to the necessary reactive power compensation capacitors and the short circuit impedance is analyzed. Electromagnetic Compatibility standards are checked in order to explain the frequent failure of the starters. One time proposed the disconnection of the capacitors during the ramps, reactive compensation is redesigned with the objective to have a 0.92 power factor in the pump installations.     

强谐波环境下的无功功率补偿技术

非线性功率用电设备产生谐波电流,导致电磁干扰、功率因数降低,由电容器、串联电抗器组成的谐波滤波装置具有谐波滤除和无功补偿两大功能。工作时不会像传统电容器组补偿那样,在提高功率因数的同时对高次谐波进行放大,而是对谐波进行吸收,提高电源质量。在电抗性补偿系统里,根据需要被补偿的功率计算得出电容,串联谐振电路的串联谐振频率由...     

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.     

Power electronics in electric utilities: static VAR compensators

The author deals with dynamic VAR compensation of electric power systems, applying power electronics for reactive power generation and control. After an overview of the emergence and status of modern, solid-state VAR compensators in utility and industrial applications, it is shown how dynamic VAR compensation increased transmittable power by providing voltage support, transient stability improvement, and power oscillation damping in electric power transmission systems. Methods of reactive power generation and control using thyristor-controlled reactors, with fixed and thyristor-switched capacitors or modern gate-turn-off (GTO) power converters that can function without AC capacitors or reactors, are described. A summary is included of the control structure and operation to provide the desired characteristics and performance in power systems applications     

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     

提高冶炼企业用电功率因数的方法

冶炼企业对中频炉进行无功补偿和谐波治理具有较高经济效益,值得在冶炼以及其他使用中频炉的企业推广。在中频炉增加MSCGD高压滤波补偿装置,不但对提高企业生产效率、设备可靠性有积极的作用,且还节省电能、保护环境。文中从企业的实际生产状况出发,分析了无功补偿和谐波治理的方法及手段。实践证明,文中所提方法效果理想。     

A bootstrapped switch employing a new clock feed-through compensation technique

Nonlinearity caused by the clock feed-through of a bootstrapped switch and its compensation techniques are analyzed. All kinds of clock feed-through compensation configurations and their drawbacks are also investigated.It is pointed out that the delay path match of the clock boosting circuit is the critical factor that affects the effective-ness of clock feed-through compensation. Based on that, a new clock feed-through compensation configuration and corresponding bootstrapped switch are presented and designed optimally with the UMC mixed-mode/RF 0.18μm 1P6M P-sub twin-well CMOS process by orientating and elaborately designing the switch MOSFETs that influence the delay path match of the clock boosting circuit. HSPICE simulation results show that the proposed clock feed-through compensation configuration can not only enhance the sampling accuracy under variations of process, power supply voltage, temperature and capacitors but also decrease the even harmonic, high-order odd harmonic and THD on the whole effectively.     

应用PSCAD软件对有源电力滤波器进行设计与仿真

有源电力滤波器功能强大,作为电力电子设备中重要的组成部分,可以较好的实现谐波的滤除,实现无功的补偿.并且其补偿特性优于无源滤波器.本文用PSCAD对投入有源电力滤波器的电力系统的运行过程进行仿真,控制系统基于瞬时无功功率理论设计,给出负荷电流发生突变时的动态响应曲线.通过仿真得出:APF在电网的谐波抑制以及无功补偿方面特性优良、模型正确、控制系统可行.     

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.