基于DSP的D-STATCOM硬件实现及控制算法

针对电网无功功率实现动态无功补偿的问题,采用模块化的设计方法,设计出一种基于DSP的D-STATCOM电路。根据瞬时无功功率理论计算参考电流和补偿电流,并采用直接电流控制方法产生补偿电流。建立了整个补偿过程的数学模型,分析了D-STATCOM中电流控制算法、电压控制算法以及IGBT晶闸管通断时间控制算法。结果表明:D-STATCOM完成无功补偿,达到抑制谐波的目的。     

基于80C196KC单片机的电力补偿装置控制系统设计

以80C196KC单片机为核心的电力补偿控制系统．通过模拟输入电路对三相电压、电流进行采样，计算后通过输出单元控制电容器的投切，从而实现对电网无功功率的补偿。本文介绍了系统硬件和软件的设计方法。     

Loss-free complex impedance network elements

The concept of loss-free complex impedance network elements (i.e., elements with active and reactive impedance components and yet loss-free) is introduced. Synthesis of such elements by means of switched-mode power converters with appropriate control has been demonstrated to be possible. Some possible power processing-related applications of these elements are indicated, such as improved matching between ac sources and loads and VAR compensation. It has further been demonstrated that loss-free complex impedance elements are suitable for modeling many power processing systems for the purpose of analysis as well as for design purposes.     

A full compensating system for general loads, based on a combination of thyristor binary compensator, and a PWM-IGBT active power filter

A full compensating system for distribution networks, able to eliminate harmonics, correct unbalanced loads, and generate or absorb reactive power, is presented. The system is based on a combination of a thyristor binary compensator (TBC), and a pulsewidth-modulation insulated gate bipolar transistor active power filter (APF) connected in cascade. The TBC compensates the fundamental reactive power and balances the load connected to the system. The APF eliminates the harmonics and compensates the small amounts of load unbalances or power factor that the TBC cannot eliminate due to its binary condition. The TBC is based on a chain of binary-scaled capacitors and one inductor per phase. This topology allows, with an adequate number of capacitors, a soft variation of reactive power compensation and a negligible generation of harmonics. The capacitors are switched on when the line voltage reaches its peak value, avoiding inrush currents generation. The inductor helps to balance the load, and absorbs reactive power when required. The APF works measuring the source currents, forcing them to be sinusoidal. The two converters (TBC and APF) work independently, making the control of the system simpler and more reliable. Simulations show that the system is able to respond to many kinds of transient perturbations in no more than a couple of cycles. The paper analyzes the circuit proposed, the way it works and shows some experimental results obtained under operation.     

无功补偿自控方案在电力设计中的应用比较

简述了无功补偿的原因和意义、补偿途径和方式。研究了传统电子式自动补偿控制方案、基于单片机控制技术的无功补偿自控方案以及基于PLC控制技术的无功补偿自控方案等设计结构和原理。并对其性能和电路结构特点进行比较,为电力设计提供参考。     

智能无功补偿技术在电力自动化中的应用分析

本文主要探讨的是关于智能无功补偿技术在电力自动化中的应用问题,在具体的分析中首先对电力自动化的定义进行了阐述,同时对于电力系统无功补偿技术也进行了分析,其次对智能无功补偿技术在电力自动化应用中的现状进行了分析,最后给出了相应的对策,旨在进一步加强智能无功补偿技术在电力自动化中的应用。     

间歇式能源发电系统无功补偿技术的研究

针对间歇式能源发电系统的特点和无功需求,提出了将无功补偿与风力并网发电相结合的设计方案,通过计算得出了间歇式能源发电系统中电缆和变压器无功损耗.本文利用Mat-lab/Simulink搭建了具有无功补偿功能的并网变流器的仿真模型,并采用有功无功解耦控制和SPWM控制方法,补偿系统所需无功以及有效抑制动态电压波动.最后,仿真结果验证了风力并网变流器在向电网提供有功功率的同时也能够提供一定容量的无功功率,提高系统功率因数,有效抑制电网电压波动.     

基于PWM的无功补偿系统设计

随着功率因数低的工业用电设备接入电网中,对电力系统运行稳定性和电压质量提出了更高的要求。文中基于无功补偿的原理,并设计了PWM连续调容的动态无功补偿系统,该系统克服了传统无功补偿器用感性无功覆盖容性无功,以产生可调容性无功的调节方式存在的不足,改进了现有无功补偿系统只能分组分级投切,不能连续调容的现状。能够快速跟踪负载变化,实时补偿无功功率,稳定电网电压,提高功率因数。     

功率因数对工厂供配电系统电能质量的影响

介绍了功率因数对工厂供配电系统电能质量的影响,为了提高电能的利用率,在此研究了如何减少感性负荷的无功储能。详细介绍了2种提高功率因数的方法：传统法和补偿法。传统法是对感性负荷自身进行改造或运行状态的改变来减少无功损耗;补偿法是通过给感性负荷并联电容器纽进行无功补偿的一种新型方法。目的是为了提高电能的利用率和减少有色金属的浪费。研究结果证明,通过这2种方法,系统的功率因数可以提高的1倍以上,对节约电能有很大的帮助。     

浅谈电力谐波对煤矿无功补偿电容器的影响

通过对谐波电流放大机理的分析,结合实例说明了电力谐波对无功补偿电容器的危害,为煤矿安全使用电容无功补偿装置提供了借鉴.     

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     

A new control philosophy for power electronic converters asfictitious power compensators

A new philosophy utilizing both thyristor-controlled reactive sources (TCR) and dynamic power filters (DPF) is proposed for applications in fictitious power compensation. The necessary network parameters for the control loops are calculated from digital time-domain, cross correlation signal processing techniques implemented with the aid of a microcomputer. Practical results that illustrate this control philosophy were obtained for a 15 kVA three-phase dynamic power filter     

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.     

三相四线制无功与谐波全补偿的并联有源电力滤波器的研究

简要分析了并联有源电力滤波器的工作原理,选取含有裂相电容的三桥臂电压源型逆变器作为系统主电路,输出电流采用动态滞环控制。针对三相四线系统,且考虑到电网电压畸变和不对称的情况,给出了一种基于瞬时功率理论实现无功功率和谐波全补偿的控制策略,并使用Matlab对系统进行了仿真。     

三相四线制无功与谐波全补偿的并联有源电力滤波器的研究

简要分析了并联有源电力滤波器的工作原理，选取含有裂相电容的三桥臂电压源型逆变器作为系统主电路，输出电流采用动态滞环控制。针对三相四线系统，且考虑到电网电压畸变和不对称的情况，给出了一种基于瞬时功率理论实现无功功率和谐波全补偿的控制策略，并使用Matlab对系统进行了仿真。     

Enhancement of Distributed Generation by Using Custom Power Device

Wind energy (WE) has become immensely popular for distributed generation (DG). This case presents the monitoring, modeling, control, and analysis of the two-level three-phase WE based DG system where the electric grid interfacing custom power device (CPD) is controlled to perform the smart exchanging of electric power as per the Indian grid code. WE is connected to DC link of CPD for the grid integration purpose. The CPD based distributed static compensator, i.e. the distributed static synchronous compensator (DSTATCOM), is utilized for injecting the wind power to the point of common coupling (PCC) and also acts against the reactive power demand. The novel indirect current control scheme of DSTATCOM regulates the power import and export between the WE and the electric grid system. It also acts as a compensator and performs both the key features simultaneously. Hence, the penetration of additional generated WE power to the grid is increased by 20% to 25%. The burden of reactive power compensation from grid is reduced by DSTATCOM. The modeling and simulation are done in MATLAB. The results are validated and verified.     

智能型动态功率因数监测与补偿系统

描述了基于单片机为控制核心的低电压动态功率因数监测与补偿系统。该系统将MOC3041与可控硅BT137结合作为补偿电容投入的控制开关,同时利用MOC3041内部的过零比较器来实现延时控制作用,成功解决了补偿电容投入时可能产生的电流冲击问题。在软件上采用PWM技术,控制"开关"通断时间及频率来改变补偿电容投入时的等效电容量,使补偿电容量连续可调。该电容补偿技术很好地实现了对当前电路稳定、可靠、精确的检测和控制。     

A Universal Vector Controller for Four-Quadrant Three-Phase Power Converters

Power factor corrected (PFC) rectifiers, active power filters (APFs), static VAR compensators (STATCOM), and grid-connected inverters (GCI) are indispensable elements in distributed generation power systems. PFC rectifiers are essential for load side harmonic and reactive power correction, APFs can suppress the harmonics generated by nonlinear loads or sources, STATCOMs can control the power flow in the grid, while GCIs are the key elements bridging the renewable energy sources and the power grid. Previous theory and experiments have demonstrated that one-cycle control is capable of controlling all above mentioned three-phase converters, featuring excellent performance, simple circuitry, and low cost. This paper further unifies the control key equations for the previously mentioned converters, which results in a universal solution that realizes all these functions with a same controller. The concept has been verified by a 1-kVA prototype and supported by a series of experimental results     

无功补偿综合实践平台的设计

无功补偿是电气工程及其自动化专业学生所必需掌握的知识点之一.本文介绍了一种无功动态补偿综合实践平台的实现方案,利用调压器、异步电动机、同步发电机及灯箱模拟可变的有功及无功负荷,通过90度接线方式利用一表法测量系统的无功需求量.该值的变化决定投入分组电容的组别,实现了无功功率的测量-无功补偿的基本原理和实现-无功补偿效果评价的综合实践体系.实践证明,学生可以将多门课程中的知识点融会贯通成知识面,加深理解的同时增强了分析问题和解决问题的能力,效果良好.     

电力变换和控制技术导论

电力的开发和应用是现代社会经济发展和人类高质量生活条件的基础,经过变换处理后再供用户使用的电能占全国总发电量的百分比值的高低是衡量一个国家技术进步的主要标志之一。文章阐述了开关型电力电子变换和控制基本原理,介绍了实用的半导体电力开关器件、电力电子开关型电源及电力电子补偿控制器的应用,最后,总结了电力电子技术的发展历史和今年十年电力电子技术变革。