为提升低惯量电力系统的小干扰稳定性,给出保障适应新能源发展的合理惯量裕度,并明确惯量分布对于互联系统小干扰稳定性的影响规律。研究了惯量分布对系统区域间振荡模式的影响规律,构建了面向区域间振荡的电力系统小扰动惯量域(Small S...为提升低惯量电力系统的小干扰稳定性,给出保障适应新能源发展的合理惯量裕度,并明确惯量分布对于互联系统小干扰稳定性的影响规律。研究了惯量分布对系统区域间振荡模式的影响规律,构建了面向区域间振荡的电力系统小扰动惯量域(Small Signal Inertia Region,SSIR)。首先,基于部分惯量中心(Part of the Center of Inertia,PCOI)等值方法和多项式Leverrier解法,构建了等值两机系统区间振荡模式阻尼比解析式。在此基础上,依据临界阻尼比构建了计及小干扰稳定约束的惯量域。进而,对区域互联系统惯量分布和小干扰稳定性之间的联系进行解析。最后,对惯量域进行全面分析,并在新能源系统中进行了初步验证。仿真结果表明,所提出的计算方法能够实现电力系统小扰动惯量域的准确、快速构建,增强低惯量电力系统小干扰稳定性的评估和监控能力,并为新能源惯量域的构建提供理论指导。展开更多
Wide area damping controller(WADC) is usually utilized to damp interarea low frequency oscillation in power system. However, conventional WADC design method neglects the influence of signal transmission delay and damp...Wide area damping controller(WADC) is usually utilized to damp interarea low frequency oscillation in power system. However, conventional WADC design method neglects the influence of signal transmission delay and damping performance of WADC designed by the conventional method may deteriorate or even has no effect when signal transmission delay is beyond delay margin, an index that denotes delay endurance degree of power system. Therefore, a new design method for WADC under the condition of expected damping factor and required signal transmission delay is presented in this work. An improved delay margin with less conservatism is derived by adopting a new Lyapunov-Krasovskii function and more compact bounding technique on the derivative of Lyapunov-Krasovskii functional. The improved delay margin, which constructs the correlation of damping factor and signal transmission delay, can be used to design WADC. WADC designed by the proposed method can ensure that power system satisfies expected damping factor when WADC input signal is delayed within delay margin. Satisfactory test results demonstrate the effectiveness of the proposed method.展开更多
利用直流输电线路的直流功率调制可以有效地抑制交直流互联电网区域间的低频振荡,而如何确定合适的直流调制控制器参数是一个研究难点。在传统的Prony分析方法中引入多信号到基于奇异值-总体最小二乘法(Singular Value Decomposed-total...利用直流输电线路的直流功率调制可以有效地抑制交直流互联电网区域间的低频振荡,而如何确定合适的直流调制控制器参数是一个研究难点。在传统的Prony分析方法中引入多信号到基于奇异值-总体最小二乘法(Singular Value Decomposed-total Least Square,SVD-TLS)确定信号阶数的改进Prony算法中,并在考虑系统初始状态的条件下辨识系统降阶传递函数,给出了不依赖电力系统的数学模型而辨识出系统降阶模型的实用步骤,有效的避开了控制器参数在以往设计中的困难。依据辨识所得结果结合极点配置法整定控制器参数。通过理论分析和IEEE四机系统验证了改进多信号Prony算法提高了辨识精度;仿真结果表明互联系统附加参数经过改进算法整定的直流调制控制器可以明显增加交直流互联系统的振荡阻尼,提高系统运行稳定性。展开更多
文摘为提升低惯量电力系统的小干扰稳定性,给出保障适应新能源发展的合理惯量裕度,并明确惯量分布对于互联系统小干扰稳定性的影响规律。研究了惯量分布对系统区域间振荡模式的影响规律,构建了面向区域间振荡的电力系统小扰动惯量域(Small Signal Inertia Region,SSIR)。首先,基于部分惯量中心(Part of the Center of Inertia,PCOI)等值方法和多项式Leverrier解法,构建了等值两机系统区间振荡模式阻尼比解析式。在此基础上,依据临界阻尼比构建了计及小干扰稳定约束的惯量域。进而,对区域互联系统惯量分布和小干扰稳定性之间的联系进行解析。最后,对惯量域进行全面分析,并在新能源系统中进行了初步验证。仿真结果表明,所提出的计算方法能够实现电力系统小扰动惯量域的准确、快速构建,增强低惯量电力系统小干扰稳定性的评估和监控能力,并为新能源惯量域的构建提供理论指导。
基金Project(51007042) supported by the National Natural Science Foundation of China
文摘Wide area damping controller(WADC) is usually utilized to damp interarea low frequency oscillation in power system. However, conventional WADC design method neglects the influence of signal transmission delay and damping performance of WADC designed by the conventional method may deteriorate or even has no effect when signal transmission delay is beyond delay margin, an index that denotes delay endurance degree of power system. Therefore, a new design method for WADC under the condition of expected damping factor and required signal transmission delay is presented in this work. An improved delay margin with less conservatism is derived by adopting a new Lyapunov-Krasovskii function and more compact bounding technique on the derivative of Lyapunov-Krasovskii functional. The improved delay margin, which constructs the correlation of damping factor and signal transmission delay, can be used to design WADC. WADC designed by the proposed method can ensure that power system satisfies expected damping factor when WADC input signal is delayed within delay margin. Satisfactory test results demonstrate the effectiveness of the proposed method.
文摘利用直流输电线路的直流功率调制可以有效地抑制交直流互联电网区域间的低频振荡,而如何确定合适的直流调制控制器参数是一个研究难点。在传统的Prony分析方法中引入多信号到基于奇异值-总体最小二乘法(Singular Value Decomposed-total Least Square,SVD-TLS)确定信号阶数的改进Prony算法中,并在考虑系统初始状态的条件下辨识系统降阶传递函数,给出了不依赖电力系统的数学模型而辨识出系统降阶模型的实用步骤,有效的避开了控制器参数在以往设计中的困难。依据辨识所得结果结合极点配置法整定控制器参数。通过理论分析和IEEE四机系统验证了改进多信号Prony算法提高了辨识精度;仿真结果表明互联系统附加参数经过改进算法整定的直流调制控制器可以明显增加交直流互联系统的振荡阻尼,提高系统运行稳定性。
