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谐波治理是高压直流(High Voltage Direct Current,HVDC)系统的关键技术之一。本文分析了应用在HVDC直流侧的直流有源滤波器工作原理,提出了近似逆系统的控制策略。并在PSCAD/EMTDC软件平台和实际装置中进行了实践。仿真和实验样机验证了逆系统控制的可行性和有效性。控制系统稳定,滤波效果优良。 相似文献
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谐波治理是高压直流(High Voltage Direct Current,HVDC)系统的关键技术之一。本文分析了应用在HVDC直流侧的直流有源滤波器工作原理,提出了近似逆系统的控制策略。并在PSCAD/EMTDC软件平台和实际装置中进行了实践。仿真和实验样机验证了逆系统控制的可行性和有效性。控制系统稳定,滤波效果优良。 相似文献
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分析了已有HVDC直流有源滤波器控制方法的优缺点,并在交流有源滤波器重复控制方法的基础上,将基于系统辨识的重复控制方法应用于HVDC直流有源滤波器。根据重复控制和系统辨识原理,结合Matlab/Simulink仿真结果对控制器结构进行优化,有效提高了系统控制性能。对比分析了不同控制对象扰动水平对辨识精度、控制器参数设置以及系统性能的影响,表明基于系统辨识的重复控制是HVDC直流有源滤波器抑制直流侧谐波电流的有效控制方法。 相似文献
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多馈入直流输电系统交流侧滤波方案的设计 总被引:14,自引:8,他引:6
随着高压直流输电(HVDC)系统的发展及多馈入直流输电系统的逐步形成,多馈入直流系统的谐波问题日显突出.由于多馈入直流系统交流侧的母线电压严重畸变,现有的针对单谐波源的滤波方案已不再适用.文章提出了一种新的适用于多馈入直流输电系统的交流侧滤波方案,即在系统与负载之间并联由无源滤波器串联有源滤波器构成的混合滤波器,再在该混合滤波器之前与负荷串联一个有源滤波器.仿真比较了采用混合有源滤波方案与只投入无源滤波器时的滤波仿真效果,结果表明混合有源滤波方案可以显著降低母线上的谐波含量,从而抑制了负载谐波对系统的影响. 相似文献
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基于直流侧电压周期离散控制的单相并联有源滤波器 总被引:7,自引:3,他引:7
针对有源滤波器电流谐波分量检测运算复杂,且在负荷电流变化时出现电源电流畸变现象,从直流侧电容电压与交、直流侧功率传递的关系出发,并结合有功电流的周期性特点,提出了基于直流侧电容电压周期离散控制的新型有源滤波器控制方法.该方法以电网电压为同步信号,在电网电压信号的过零点采样直流侧电容电压,并通过周期离散控制可以获得负荷电流有功分量.采用该周期离散控制方法可实现对直流侧电容电压的线性化控制,并使有源滤波器对谐波的补偿是瞬时的.该文给出了单相并联有源滤波器的直流侧模型,基于该模型推导出周期离散控制方法.以该方法研制了10kVA有源滤波器样机,仿真和实验结果表明该方法控制简单,稳定性好,谐波补偿速度快,能够有效地避免负荷变化时的电流畸变现象. 相似文献
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用于HVDC极线电流测量的光纤电流传感器 总被引:2,自引:0,他引:2
高压直流输电系统极线线路上的直流电流是高压直流输电系统运行、控制过程中的重要技术参数。由于直流线路中换流装置产生的叠加在直流线路上的谐波电流会干扰邻近的通信线路,这就要求电流传感器能提供准确的谐波电流信号给有源滤波器以有效地抑制谐波电流。基于此,研制了一种适用于高压环境下的光纤电流传感器,直流测量准确可靠,响应快速,谐波测量频带范围宽广,准确度高;介绍了光纤电流测量系统的原理、结构以及设计中采用的关键技术。 相似文献
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Su Ling Zhao Dong-yuan Chen Jian-ye Wang Zan-ji 《Frontiers of Electrical and Electronic Engineering in China》2006,1(4):367-370
In order to eliminate the characteristic harmonics in high voltage direct current (HVDC) transmission systems and to simplify
the analog controller structure, this paper proposes a new digital controller by adopting an approximate inverse system control
strategy according to the frequency response characteristic of the hybrid power filter. The proposed digital controller is
implemented with a TMS320C32 DSP, including a series of parallel digital band-pass filters, phase shifters and amplifiers.
The results of both simulations based on PSCAD and experiments on a 30 kVA HVDC system prove that the proposed digital control
system is stable and efficient for eliminating the harmonics.
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Translated from Journal of Tsinghua University (Natural Science Edition), 2005, 45(10): 1305–1308 (in Chinese) by HUANG Zhen-hua 相似文献
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The Voltage Source Converter based HVDC provides asynchronous interconnection between two AC systems. The use of VSC HVDC enables independent control of real and reactive power. Unlike conventional HVDC, the VSC HVDC does not cause Subsynchronous Resonance (SSR) when it is close to turbo-generators. The system strength of long ac transmission line can be enhanced by providing series compensation. However, there is a possibility of SSR interaction with turbine-generator due to the presence of the series capacitor in transmission line and may lead to shaft failure of the turbine-generator. The objective of this paper is to analyze the damping of subsynchronous resonance when the series compensated long AC line and VSC HVDC are originated from the same substation. A simple method for the extraction of subsynchronous component of line current using filter is proposed. The extracted subsynchronous frequency current is injected by the VSC HVDC converter close to the turbine-generator. This suppresses the subsynchronous current flowing through the generator and increases the damping of the system at critical torsional frequencies. This technique is termed as Subsynchronous Current Injection (SSCI). Subsynchronous current injector is designed using D–Q model of VSC HVDC. Genetic Algorithm (GA) is used for tuning the converter controllers and filter parameters. The results show the effectiveness of the proposed subsynchronous current injector in damping of SSR. 相似文献
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为提升混合级联直流输电系统接入点的电能质量,减少工程占地与造价,提出了一种基于模块化多电平换流器的主动谐波补偿方法.首先,介绍了混合级联直流输电系统的拓扑结构和谐波特征,其中高压阀组采用电网换相换流器,低压阀组则采用模块化多电平换流器.然后,介绍了系统的谐波等值电路与主动谐波补偿控制策略,通过模块化多电平换流器对电网换相换流器的谐波进行补偿,并分析了主动谐波补偿对模块化多电平换流器稳态运行的影响.最后,在PSCAD/EMTDC仿真软件中搭建了混合级联直流输电系统的仿真模型,验证了主动谐波补偿控制策略在系统稳态运行、功率变化和计及延时工况下的有效性. 相似文献
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现有三极直流输电系统基于晶闸管换流器,存在一些与传统直流输电系统相似的固有缺陷。文中提出了一种改进系统:极3采用基于全桥子模块的模块化多电平换流器,极1和极2采用基于钳位双子模块的模块化多电平换流器。同时,提出了三极直流协调控制策略,并且为了抑制过渡阶段的暂态过电压,减小接地电流和功率波动,还提出了电压反向控制、电流维零控制和功率协调控制。采用PSCAD/EMTDC进行仿真验证,结果表明利用所提控制策略,三极直流输电系统能够获得较好的响应特性,在维持电容电压平衡的同时,能够抑制交直流间功率扰动和接地极电流波动。 相似文献
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Abstract—This article proposes a photovoltaic and battery interfaced series hybrid active power filter, which is comprised of a series active power filter and an inductor-capacitor (LC) shunt passive filter. The main benefits of the proposed system provide the compensation against the voltage harmonics, current harmonics, and voltage interruption for the whole day. A series active power filter demands a source of energy for compensating the voltage sag/swell. The proposed topology utilizes the green energy source with an energy storage unit to meet the DC-link voltage requirement of the series active power filter. The control strategy is based on the dual formulation of the compensation system principles with adaptive fuzzy logic controller. The simulation and experimental studies are carried out to validate the effectiveness of the proposed photovoltaic interfaced three-phase four-wire series hybrid active power filter. 相似文献
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针对电气化铁道牵引网的电气特性和无功补偿装置的现实条件,提出基于神经网络和专家系统相结合的晶闸管投切电容器复合控制方案。利用神经网络构造多路自适应噪声对消滤波器,并行地在线检测出牵引网的无功电流、有功电流和高次谐波电流;以无功电流差补值作为控制参量,并以高次谐波电流作为谐振保护信号,由专家系统给出投切无功补偿电容的控制指令。特性分析表明,该系统有效提高了系统功率因数,降低了无功补偿电容的投切频率,安全可靠性高,是牵引电网晶闸管投切电容进行无功补偿的优选控制方案。 相似文献