为实现三相电压跌落的快速精确检测,提出含稳态分量和补偿分量的解耦检测方法。首先运用瞬时对称分量法在坐标系中推导出基波电压正序、负序分量的解耦检测模型;然后根据该解耦模型构建含稳态分量和补偿分量的离散卡尔曼滤波器,采用数...为实现三相电压跌落的快速精确检测,提出含稳态分量和补偿分量的解耦检测方法。首先运用瞬时对称分量法在坐标系中推导出基波电压正序、负序分量的解耦检测模型;然后根据该解耦模型构建含稳态分量和补偿分量的离散卡尔曼滤波器,采用数学形态滤波器和网格分形方法定位电压突变发生和恢复时刻,并重置卡尔曼滤波器参数以加快检测动态响应速度;最后将提出的检测方法用于各种电压故障情形下的检测和动态电压恢复器(dynamic voltage restorer,DVR)补偿仿真中。仿真结果表明,所提方法的检测动作时间为2~3个采样周期,与传统dq变换法相比,其动态响应速度快一个数量级,证明了所提解耦检测方法在响应速度、稳态精度方面具有优越性。展开更多
中压动态电压恢复器(dynamic voltage restorer,DVR)可用于有效保护大范围的用户不受电压暂降的影响,但不能补偿其下游馈线上发生故障时的电压扰动。提出了将DVR控制为虚拟阻抗的方法,推导了系统传递函数,利用Bode图与劳斯-赫尔维茨(Rou...中压动态电压恢复器(dynamic voltage restorer,DVR)可用于有效保护大范围的用户不受电压暂降的影响,但不能补偿其下游馈线上发生故障时的电压扰动。提出了将DVR控制为虚拟阻抗的方法,推导了系统传递函数,利用Bode图与劳斯-赫尔维茨(Routh-hurwitz)稳定判据,分析了控制DVR为虚拟阻抗的可行性和系统稳定性。给出了将DVR控制为虚拟电感从而实现故障限流器,以及将DVR控制为虚拟电容从而实现串联补偿的方法。通过仿真和实验验证了所提方案的可行性与有效性。为拓展中压DVR的功能,提高其实用化水平提供了参考。展开更多
Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultan...Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultaneous reactive power injection for UPQC(namely UPQC-SRI) is proposed to address the issue of voltage sag. The proposed UPQC-SRI determines the injection angle of compensation voltage with consideration of optimal configuration of UPQC current-carrying.Moreover, the compensation strategy also considers the current-carrying limit of UPQC, and then the zero active power injection region of UPQC-SRI(also called UPQCSRI region) is obtained. Under the conditions which exceed the UPQC-SRI region, the limit value of shunt current is determined by this proposed strategy. Finally, the proposed strategy and the corresponding algorithm are verified under the PSCAD/EMTDC platform. The result indicates the proposed UPQC-SRI strategy in this paper can provide more persistent voltage sag compensation than the previous strategies for the sensitive load.展开更多
文摘为实现三相电压跌落的快速精确检测,提出含稳态分量和补偿分量的解耦检测方法。首先运用瞬时对称分量法在坐标系中推导出基波电压正序、负序分量的解耦检测模型;然后根据该解耦模型构建含稳态分量和补偿分量的离散卡尔曼滤波器,采用数学形态滤波器和网格分形方法定位电压突变发生和恢复时刻,并重置卡尔曼滤波器参数以加快检测动态响应速度;最后将提出的检测方法用于各种电压故障情形下的检测和动态电压恢复器(dynamic voltage restorer,DVR)补偿仿真中。仿真结果表明,所提方法的检测动作时间为2~3个采样周期,与传统dq变换法相比,其动态响应速度快一个数量级,证明了所提解耦检测方法在响应速度、稳态精度方面具有优越性。
文摘中压动态电压恢复器(dynamic voltage restorer,DVR)可用于有效保护大范围的用户不受电压暂降的影响,但不能补偿其下游馈线上发生故障时的电压扰动。提出了将DVR控制为虚拟阻抗的方法,推导了系统传递函数,利用Bode图与劳斯-赫尔维茨(Routh-hurwitz)稳定判据,分析了控制DVR为虚拟阻抗的可行性和系统稳定性。给出了将DVR控制为虚拟电感从而实现故障限流器,以及将DVR控制为虚拟电容从而实现串联补偿的方法。通过仿真和实验验证了所提方案的可行性与有效性。为拓展中压DVR的功能,提高其实用化水平提供了参考。
基金supported by the twelfth five-year National Mega-projects of Science and Technology (2011BAA01B03)
文摘Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultaneous reactive power injection for UPQC(namely UPQC-SRI) is proposed to address the issue of voltage sag. The proposed UPQC-SRI determines the injection angle of compensation voltage with consideration of optimal configuration of UPQC current-carrying.Moreover, the compensation strategy also considers the current-carrying limit of UPQC, and then the zero active power injection region of UPQC-SRI(also called UPQCSRI region) is obtained. Under the conditions which exceed the UPQC-SRI region, the limit value of shunt current is determined by this proposed strategy. Finally, the proposed strategy and the corresponding algorithm are verified under the PSCAD/EMTDC platform. The result indicates the proposed UPQC-SRI strategy in this paper can provide more persistent voltage sag compensation than the previous strategies for the sensitive load.