On the basis of the theoretical analysis of a single-machine infinite-bus （SMIB）, using the modified linearized Phil- lips-Heffron model installed with unified power flow controller （UPFC）, the potential of the UP...On the basis of the theoretical analysis of a single-machine infinite-bus （SMIB）, using the modified linearized Phil- lips-Heffron model installed with unified power flow controller （UPFC）, the potential of the UPFC supplementary controller to enhance the dynamic stability of a power system is evaluated by measuring the electromechanical controllability through singular value decomposition （SVD） analysis. This controller is tuned to simultaneously shift the undamped electromeehanical modes to a prescribed zone in the s-plane. The problem of robust UPFC based damping controller is formulated as an optimization problem according to the eigenvalue-based multi-objective function comprising the damping factor, and the damping ratio of the undamped electromechanical modes to be solved using gravitational search algorithm （GSA） that has a strong ability to find the most optimistic results. The different loading conditions are simulated on a SMIB system and the rotor speed deviation, internal voltage deviation, DC voltage deviation and electrical power deviation responses are studied with the effect of this flexible AC transmission systems （FACTS） controller. The results reveal that the tuned GSA based UPFC controller using the proposed multi-objective function has an excellent capability in damping power system with low frequency oscillations and greatly enhances the dynamic stability of the power systems.展开更多
随着新能源发电比例越来越高,其受电网三相不平衡的影响越来越明显,尤其负序超标是导致电力系统安全性降低的重要原因。统一潮流控制器(unified power flow controller,UPFC)具有调节各序电流输出的能力,可用于提升系统的平衡性。为此,...随着新能源发电比例越来越高,其受电网三相不平衡的影响越来越明显,尤其负序超标是导致电力系统安全性降低的重要原因。统一潮流控制器(unified power flow controller,UPFC)具有调节各序电流输出的能力,可用于提升系统的平衡性。为此,首先建立基于解耦-补偿原理的UPFC正序最优补偿潮流算法;其次构建UPFC的负序补偿电流控制模型,将电压不平衡补偿的优化求解问题归结为凸二次约束二次规划(quadratically constrained quadratic programming,QCQP)问题,并采用原-对偶内点法求取UPFC的负序电流最优输出值;最后提出计及正序网损与负序电压指标的负序电压补偿最优潮流(optimal power flow,OPF)计算方法以及区域负序电压总体补偿策略。通过算例分析验证所提出方法的可行性与有效性。展开更多
基于传统的比例—积分控制,提出了统一潮流控制器(unified power flow controller,UPFC)并、串联侧解耦的系统级控制策略,其控制目的是在并联侧维持UPFC并入点的交流电压和直流侧电容电压,在串联侧控制线路有功、无功潮流。文章首先介...基于传统的比例—积分控制,提出了统一潮流控制器(unified power flow controller,UPFC)并、串联侧解耦的系统级控制策略,其控制目的是在并联侧维持UPFC并入点的交流电压和直流侧电容电压,在串联侧控制线路有功、无功潮流。文章首先介绍了所研制的UPFC实验系统平台,并在此基础上详细地给出了UPFC系统级控制器的硬件实现,实验平台的通用性决定了不同控制策略可以较容易地实现。为验证所提出的控制策略的控制效果,文中将UPFC实验装置嵌入至自行搭制的等效双机实验系统中,实验结果与PSCAD/EMTDC仿真环境下的时域动态仿真结果十分相似,从而得到了良好的UPFC动态特性。展开更多
为了将统一潮流控制器UPFC(unified power flow controlle)r嵌入到商业软件中,采用节点注入电流法建立了UPFC的潮流控制模型。该模型通过控制UPFC串联侧节点的注入电流和并联侧节点的无功注入电流来控制线路潮流和UPFC接入点母线电压,其...为了将统一潮流控制器UPFC(unified power flow controlle)r嵌入到商业软件中,采用节点注入电流法建立了UPFC的潮流控制模型。该模型通过控制UPFC串联侧节点的注入电流和并联侧节点的无功注入电流来控制线路潮流和UPFC接入点母线电压,其中,串联侧节点的注入电流通过功率目标方程直接求取,并联侧节点的无功注入电流通过引入被控母线电压的参考值与实际值的偏差求得。基于电力系统分析综合程序PSASP(power system analysis software package)进行了算例研究,结果表明所建模型能有效实现UPFC的潮流控制作用,且具有较快的潮流追踪速度和较高的收敛精度。对其他FACTS(flexible AC transmission system)器件的控制建模具有一定的参考价值。展开更多
文摘On the basis of the theoretical analysis of a single-machine infinite-bus （SMIB）, using the modified linearized Phil- lips-Heffron model installed with unified power flow controller （UPFC）, the potential of the UPFC supplementary controller to enhance the dynamic stability of a power system is evaluated by measuring the electromechanical controllability through singular value decomposition （SVD） analysis. This controller is tuned to simultaneously shift the undamped electromeehanical modes to a prescribed zone in the s-plane. The problem of robust UPFC based damping controller is formulated as an optimization problem according to the eigenvalue-based multi-objective function comprising the damping factor, and the damping ratio of the undamped electromechanical modes to be solved using gravitational search algorithm （GSA） that has a strong ability to find the most optimistic results. The different loading conditions are simulated on a SMIB system and the rotor speed deviation, internal voltage deviation, DC voltage deviation and electrical power deviation responses are studied with the effect of this flexible AC transmission systems （FACTS） controller. The results reveal that the tuned GSA based UPFC controller using the proposed multi-objective function has an excellent capability in damping power system with low frequency oscillations and greatly enhances the dynamic stability of the power systems.
文摘随着新能源发电比例越来越高,其受电网三相不平衡的影响越来越明显,尤其负序超标是导致电力系统安全性降低的重要原因。统一潮流控制器(unified power flow controller,UPFC)具有调节各序电流输出的能力,可用于提升系统的平衡性。为此,首先建立基于解耦-补偿原理的UPFC正序最优补偿潮流算法;其次构建UPFC的负序补偿电流控制模型,将电压不平衡补偿的优化求解问题归结为凸二次约束二次规划(quadratically constrained quadratic programming,QCQP)问题,并采用原-对偶内点法求取UPFC的负序电流最优输出值;最后提出计及正序网损与负序电压指标的负序电压补偿最优潮流(optimal power flow,OPF)计算方法以及区域负序电压总体补偿策略。通过算例分析验证所提出方法的可行性与有效性。
文摘基于传统的比例—积分控制,提出了统一潮流控制器(unified power flow controller,UPFC)并、串联侧解耦的系统级控制策略,其控制目的是在并联侧维持UPFC并入点的交流电压和直流侧电容电压,在串联侧控制线路有功、无功潮流。文章首先介绍了所研制的UPFC实验系统平台,并在此基础上详细地给出了UPFC系统级控制器的硬件实现,实验平台的通用性决定了不同控制策略可以较容易地实现。为验证所提出的控制策略的控制效果,文中将UPFC实验装置嵌入至自行搭制的等效双机实验系统中,实验结果与PSCAD/EMTDC仿真环境下的时域动态仿真结果十分相似,从而得到了良好的UPFC动态特性。
文摘为了将统一潮流控制器UPFC(unified power flow controlle)r嵌入到商业软件中,采用节点注入电流法建立了UPFC的潮流控制模型。该模型通过控制UPFC串联侧节点的注入电流和并联侧节点的无功注入电流来控制线路潮流和UPFC接入点母线电压,其中,串联侧节点的注入电流通过功率目标方程直接求取,并联侧节点的无功注入电流通过引入被控母线电压的参考值与实际值的偏差求得。基于电力系统分析综合程序PSASP(power system analysis software package)进行了算例研究,结果表明所建模型能有效实现UPFC的潮流控制作用,且具有较快的潮流追踪速度和较高的收敛精度。对其他FACTS(flexible AC transmission system)器件的控制建模具有一定的参考价值。
