统一潮流控制器(unified power flow controller,UPFC)传统三状态模型仅考虑降额,四状态模型仅考虑单换流器继续运行情况,该文兼顾两者,扩展得到UPFC九状态模型,并计及UPFC与单独串补、并补方式相互重叠,以获得更为精确的设备停运概率...统一潮流控制器(unified power flow controller,UPFC)传统三状态模型仅考虑降额,四状态模型仅考虑单换流器继续运行情况,该文兼顾两者,扩展得到UPFC九状态模型,并计及UPFC与单独串补、并补方式相互重叠,以获得更为精确的设备停运概率。利用矩阵描述频率和持续时间法分层等值,建立换流器通用备用模型,以及可以量化UPFC实现不同功能的等值模型。新推导出分层等值系统状态概率、频率和持续时间灵敏度公式,弥补连续修改参数法求UPFC模型灵敏度的不足。算例分析UPFC可靠性指标及其灵敏度,帮助辨识薄弱环节、优化结构和参数,分别采用全微分公式和连续修改参数法,验证所提模型的正确性和有效性。展开更多
We in this paper give a decomposition concerning the general matrix triplet over an arbitrary divisionring F with the same row or column numbers. We also design a practical algorithm for the decomposition of thematrix...We in this paper give a decomposition concerning the general matrix triplet over an arbitrary divisionring F with the same row or column numbers. We also design a practical algorithm for the decomposition of thematrix triplet. As applications, we present necessary and suficient conditions for the existence of the generalsolutions to the system of matrix equations DXA = C1, EXB = C2, F XC = C3 and the matrix equation AXD + BY E + CZF = Gover F. We give the expressions of the general solutions to the system and the matrix equation when thesolvability conditions are satisfied. Moreover, we present numerical examples to illustrate the results of thispaper. We also mention the other applications of the equivalence canonical form, for instance, for the compressionof color images.展开更多
Electromagnetic transient simulation for large-scale power system is a time-consuming problem.A new frequency-dependent equivalence method is presented in the paper,which might significantly accelerate power system el...Electromagnetic transient simulation for large-scale power system is a time-consuming problem.A new frequency-dependent equivalence method is presented in the paper,which might significantly accelerate power system electromagnetic transient simulation.In the method,an effective algorithm is designed to directly transfer the port admittance determinant of external system's mixing matrix into admittance rational function;and the step-by-step strategy for the equivalence of actual large system is put forward,which further reduces the calculation quantities needed.Moreover,the study of multiple real root pole characteristics of admittance transfer function of two-port network is performed and a proposition is achieved.Based on the proposition and residue theorem,the equivalence system for external system corresponding to the admittance rational function is obtained.The computation complexity of the step-by-step equivalence method is about o(┌n/np×T┐)(┌┐ is upper integral operation,n is the total buses number of external system,N P is the total buses number of single step equivalence network,T is single step equivalence time),which indicates that the computation complexity of the method proposed has nearly linear relationship with the buses number of external system,and the method proposed has satisfactory computation speed.Since the mixing matrix of external system includes all the information of external system,therefore,port admittance rational function derived from it can reflect its full frequency characteristic and the equivalence network achieved has high equivalence precision.Moreover,since the port rational function is gained at the condition of the external system without source,which equals stable passive network,it could not show any unstable pole and need not extra measure to make the equivalence system stable.The test results of the samples and comparison with other methods demonstrate that the new method proposed is valid and effective.展开更多
The organizational problem is how to arrange the order of play for the annual club tournament under the following cocnditions. There are n many teams enter and one court available. The tournament rules are that team h...The organizational problem is how to arrange the order of play for the annual club tournament under the following cocnditions. There are n many teams enter and one court available. The tournament rules are that team has to play a match against every other team. Each team should have a reasonalbe rest between games. We give some method to consider the problem and completely solve the problem in the case that n=5展开更多
文摘统一潮流控制器(unified power flow controller,UPFC)传统三状态模型仅考虑降额,四状态模型仅考虑单换流器继续运行情况,该文兼顾两者,扩展得到UPFC九状态模型,并计及UPFC与单独串补、并补方式相互重叠,以获得更为精确的设备停运概率。利用矩阵描述频率和持续时间法分层等值,建立换流器通用备用模型,以及可以量化UPFC实现不同功能的等值模型。新推导出分层等值系统状态概率、频率和持续时间灵敏度公式,弥补连续修改参数法求UPFC模型灵敏度的不足。算例分析UPFC可靠性指标及其灵敏度,帮助辨识薄弱环节、优化结构和参数,分别采用全微分公式和连续修改参数法,验证所提模型的正确性和有效性。
基金supported by National Natural Science Foundation of China (GrantNo. 60672160)the Ph.D. Programs Foundation of Ministry of Education of China (Grant No. 20093108110001)+3 种基金the Scientific Research Innovation Foundation of Shanghai Municipal Education Commission (Grant No. 09YZ13)the Netherlands Organization for Scientific Research (NWO)Singapore MoE Tier 1 Research Grant RG60/07Shanghai Leading Academic Discipline Project (Grant No. J50101)
文摘We in this paper give a decomposition concerning the general matrix triplet over an arbitrary divisionring F with the same row or column numbers. We also design a practical algorithm for the decomposition of thematrix triplet. As applications, we present necessary and suficient conditions for the existence of the generalsolutions to the system of matrix equations DXA = C1, EXB = C2, F XC = C3 and the matrix equation AXD + BY E + CZF = Gover F. We give the expressions of the general solutions to the system and the matrix equation when thesolvability conditions are satisfied. Moreover, we present numerical examples to illustrate the results of thispaper. We also mention the other applications of the equivalence canonical form, for instance, for the compressionof color images.
基金supported by the National Natural Science Foundation ofChina (Grant No. 51177107)
文摘Electromagnetic transient simulation for large-scale power system is a time-consuming problem.A new frequency-dependent equivalence method is presented in the paper,which might significantly accelerate power system electromagnetic transient simulation.In the method,an effective algorithm is designed to directly transfer the port admittance determinant of external system's mixing matrix into admittance rational function;and the step-by-step strategy for the equivalence of actual large system is put forward,which further reduces the calculation quantities needed.Moreover,the study of multiple real root pole characteristics of admittance transfer function of two-port network is performed and a proposition is achieved.Based on the proposition and residue theorem,the equivalence system for external system corresponding to the admittance rational function is obtained.The computation complexity of the step-by-step equivalence method is about o(┌n/np×T┐)(┌┐ is upper integral operation,n is the total buses number of external system,N P is the total buses number of single step equivalence network,T is single step equivalence time),which indicates that the computation complexity of the method proposed has nearly linear relationship with the buses number of external system,and the method proposed has satisfactory computation speed.Since the mixing matrix of external system includes all the information of external system,therefore,port admittance rational function derived from it can reflect its full frequency characteristic and the equivalence network achieved has high equivalence precision.Moreover,since the port rational function is gained at the condition of the external system without source,which equals stable passive network,it could not show any unstable pole and need not extra measure to make the equivalence system stable.The test results of the samples and comparison with other methods demonstrate that the new method proposed is valid and effective.
文摘The organizational problem is how to arrange the order of play for the annual club tournament under the following cocnditions. There are n many teams enter and one court available. The tournament rules are that team has to play a match against every other team. Each team should have a reasonalbe rest between games. We give some method to consider the problem and completely solve the problem in the case that n=5