共查询到20条相似文献,搜索用时 31 毫秒
1.
Stabilization of a Power System Including Inverter‐Type Distributed Generators by a Virtual Synchronous Generator
下载免费PDF全文
![点击此处可从《Electrical Engineering in Japan》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The capacity of distributed generators (DGs) connected to the grid by inverters is growing year after year. The inverters are generally controlled by a phase locked loop (PLL) in order to achieve synchronization with the power system frequency. Power systems may become unstable as the capacity of the inverter‐type DGs continues to increase, because the inverter frequency is controlled just to follow the frequency determined by other synchronous generators. It has been suggested that inverters be controlled to behave like a synchronous generator. This concept is referred to as the virtual synchronous generator (VSG). In this paper, a control scheme for a VSG is presented, and the design method for the required energy storage and the capacity for grid stabilization control by a VSG is investigated by computer simulations. 相似文献
2.
Characteristics of Parallel Operation of Inverter‐Type Distributed Generators Operated by a Virtual Synchronous Generator
下载免费PDF全文
![点击此处可从《Electrical Engineering in Japan》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The capacity of distributed generators (DGs) connected to a grid by inverters is growing. The inverters are generally controlled by a phase locked loop (PLL) in order to achieve synchronization with the power system frequency. They cannot have synchronous power. Power systems become unstable if the capacity of the inverter‐type DGs is increased. The concept of controlling inverters to behave like a synchronous generator is studied in this paper. The result is referred to as a “virtual synchronous generator” (VSG). The VSG has synchronous power. Power systems become stable as a result of using the VSG. The VSG is useful in the parallel operation of DGs. The VSG can synchronize with other VSGs, synchronous generators, or the grid. In this paper, a method for the synchronous operation of a VSG is studied, and experimental results on a VSG running in parallel with a synchronous generator and other VSGs are presented. 相似文献
3.
4.
提出一种新型三相恒压恒频(Constant-Voltage Constant-Frequence,简称CVCF)SVPWM逆变电源闭环控制策略,目的是简化控制结构并同时保持良好的控制性能。在分析两相同步旋转坐标系下逆变器输出侧数学模型的基础上。提出一种新型闭环控制策略。该方法令两相同步旋转坐标系的d轴沿输出电压矢量方向,并对输出电压d,q轴分量分别进行PI调节。利用向量图分析了所提出的控制策略的有效性。该新型闭环控制策略只需两个电压霍尔,控制结构非常简单。仿真和实验结果均证明,本文提出的闭环控制策略具有很好的稳态及动态性能。 相似文献
5.
基于DSP的有效消除数字控制延时的UPS逆变器多环控制策略 总被引:4,自引:0,他引:4
基于逆变器离散动态模型提出了一种高性能UPS逆变器多环控制方案,在数字控制UPS逆变器中,控制延时是限制其动态性能的一个重要因素,本文详细分析了不同控制延时对多环控制逆变器性能的影响,比较了各种消除逆变器控制延时的方法,采用了更改PWM有效模式的方法以有效消除控制延时,该方法简单可靠,不会涉及预测误差,并且很容易用DSP控制器实现。控制延时的有效消除极大改进了逆变器系统的稳定性和鲁棒性。此外,内外环增益通过无差拍控制理论确定以实现快速动态响应。将本文提出的控制策略应用于16位定点DSP控制的3.3kVA的逆变器样机中,并对比了传统的多环控制逆变器系统,仿真和实验结果表明,本文提出的控制方法能实现非线性负载下低THD(<1.9%),快速动态响应,适用于线性和非线性负载。 相似文献
6.
虚拟同步发电机(virtual synchronous generator,VSG)通常用作微网逆变器中各种分布式电源的接口,以便使系统具有更大的惯性。负荷中的不平衡和非线性负载会对逆变器输出电压造成的影响。为此,设计了一种电压自适应滑模控制器。以VSG作为基础控制器,然后根据系统在αβ坐标系下的方程,将系统的负载电流作为扰动,设计自适应扰动补偿,使系统能在保持稳定的条件下,减少输出电压的抖振。最后,对控制策略进行仿真,结果验证了控制策略在电压不平衡与谐波抑制方面的有效性与鲁棒性,提高了微网逆变器输出电压的电能质量,减少了并联逆变器之间的环流。 相似文献
7.
在风力发电中低电压穿越要求为:当电网电压降落的时候,风力发电机不脱网且能够稳定电网电压和频率。风力发电机需要较高的功率和电压等级。因此,多电平中中点箝位型三电平逆变器非常适合这种设备。和其它控制方法相比,模型预测控制具有动态响应快和跟踪性能好的优点,但是工作频率低。为了能够满足低电压穿越的要求,提出一种模型预测控制方法实现NPC三电平逆变器的风力转换。所提模型预测控制也能够实现NPC逆变器中点平衡控制,通过选择冗余小矢量实现。仿真和实验验证了所提算法正确性。 相似文献
8.
基于DSP的有源逆变复合控制 总被引:1,自引:0,他引:1
在分析了电压源型逆变器基本工作原理和相量关系的基础上,阐述了一种适合大功率逆变装置的复合控制方案.通过前馈与反馈控制技术,该方案实现了对系统输出电流的良好跟踪和简单控制.基于TMS320F240DSP构建全数字化试验系统,简化了系统硬件电路,提高了系统的可靠性.试验证实了复合控制方案的正确性和有效性,并显示出系统良好的动静态性能. 相似文献
9.
Muhammad Bilal Waheed Muhammad Amjad Yasir Saleem Shahab Ahmad Niazi Suhail Khokhar 《电力部件与系统》2019,47(14-15):1287-1302
AbstractThis article proposes current control strategy for four-leg two-level voltage source inverters (VSI). This strategy is based on model predictive control (MPC) approach and presents its comparison with finite control set (FCS) model technique. Besides providing a fast dynamic response, proposed technique replaces complex modulation stage and PI controller being used in earlier classical control techniques. Moreover, the proposed methodology selects the switching sequence which reduces tracking error between output and applied reference currents using cost function optimization. This shows the improvement of system response like FCS model technique. However, FCS model technique results in calculation stress and computation burden; resulting computational delay and extra power consumption by the processor. This problem is solved with the help of proposed single predictive technique which makes the inverter more suitable for large time horizon operations and small sampling time instants. The computational delay is reduced up to 6% compared to the case of FCS-MPC controlled inverter. Performance of proposed simplified technique is analyzed and compared with FCS-MPC controlled system with the help of different types of reference signals. This work will boost the industrial application of four-leg two-level VSI by increasing dynamic response and removing complex modulation stage. 相似文献
10.
11.
三态准PWM电流滞环控制逆变器分析与实现 总被引:5,自引:2,他引:3
深入分析并研究了三态准PW M 电流滞环控制技术及其在逆变器中的应用。三态准PW M 电流滞环控制逆变器,具有输出频谱特性优,输出滤波器设计容易,输出波形质量高,开关损耗小,稳定性好,静态精度高,动态响应快等优良的综合性能。试验结果与理论分析一致。 相似文献
12.
Xu Faxi Wang Nianchun Cheng Ming 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(4):427-433
Dual‐loop control of the instantaneous values plays an important role in inverters whose output waveform has fast dynamic response, high steady‐state accuracy, and strong anti‐interference performances. Double closed‐loop control approaches that are widely used can be considered as those of the inner‐loop inductor current and capacitor current. However, the anti‐interference performance and the dynamic response speed of the former are not fast enough. Meanwhile, the latter cannot provide good overcurrent protection for the inverter source. Based on state‐space theory, the PI–PI control strategy of inner‐loop inductor current and outer‐loop voltage with feed‐forward control of the load current is adopted in this paper to further reduce the steady‐state error of the inverter system and improve its dynamic anti‐interference performance. The approach proposed in this paper can present fast and high‐stability performances as well as an effective overcurrent protection for the inverters. We verify the correctness of this approach by simulation and experiments, which prove the improved effectiveness of the approach through the output voltage waveform of the system. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
13.
越来越多的可再生能源,通过逆变器并联接入电网运行,带来了逆变器并网控制研究这一新课题。常用的分布式能源控制策略为下垂控制,当逆变器电源采用下垂控制策略时,可以通过下垂特性来分配各自承担负荷的大小,但是却很难在扰动情况下,为系统提供惯性与阻尼支撑,电力系统易失去稳定。针对此问题,提出了一种虚拟同步发电机(VSG)技术。通过研究分析同步发电机的数学模型和外特性,从而建立虚拟同步发电机的数学模型,来模拟同步发电机的转子惯性,并通过仿真验证其正确性以及虚拟同发电机技术能实现微电网并网与孤岛模式的自由切换。 相似文献
14.
PWM逆变器的直流侧等效模型研究 总被引:7,自引:0,他引:7
在三相并网型太阳能、风力发电系统和交-直-交变频调速传动系统当中,PWM逆变器作为直流侧的典型负载,其直流侧的静、动态行为,对于其前端变流器的建模、控制方法及静动态性能研究和系统设计都具有重要作用。该文通过研究逆变器与四象限变流器(4QC)拓扑结构的统一性,将4QC的状态空间平均(SSA)模型经过移植得到逆变器的SSA模型,进而提出逆变器直流侧的等效数学模型和近似简化等效模型;通过理论分析和仿真研究揭示PWM逆变器的直流侧等效模型与逆变器及交流侧电路参数之间的定量关系,并给出等效模型的参数设计公式。仿真与实验研究结果证明了所建模型及理论分析的正确性与可行性。 相似文献
15.
16.
低压微电网中,采用虚拟同步发电机(virtual synchronous generator,VSG)策略控制多台逆变器并联运行时,由于线路阻抗差异较大,无法实现输出功率的按容量精确分配。针对这一问题,文章提出一种改进的VSG控制技术,在无功电压控制环中引入公共点电压反馈和积分环节,消除线路阻抗对无功分配的影响;并在虚拟阻抗环引入无功功率反馈,根据系统运行情况实时调整虚拟阻抗的阻值。在Matlab/Simulink环境下搭建了仿真模型,仿真结果表明,所提改进控制策略实现了有功和无功功率的精确分配,降低了逆变器输出电压幅值跌落,并且具有较强的鲁棒性。 相似文献
17.
18.
在三相并网型太阳能、风力发电系统和交-直-交变频调速传动系统当中,PWM逆变器作为直流侧的典型负载,其直流侧的静、动态行为,对于其前端变流器的建模、控制方法及静动态性能研究和系统设计都具有重要作用。该文通过研究逆变器与四象限变流器(4QC)拓扑结构的统一性,将4QC的状态空间平均(SSA)模型经过移植得到逆变器的SSA模型,进而提出逆变器直流侧的等效数学模型和近似简化等效模型;通过理论分析和仿真研究揭示PWM逆变器的直流侧等效模型与逆变器及交流侧电路参数之间的定量关系,并给出等效模型的参数设计公式。仿真与实验研究结果证明了所建模型及理论分析的正确性与可行性。 相似文献
19.