Short-term power flow analysis has a significant influence on day-ahead generation schedule. This paper proposes a time series model and prediction error distribution model of wind power output. With the consideration...Short-term power flow analysis has a significant influence on day-ahead generation schedule. This paper proposes a time series model and prediction error distribution model of wind power output. With the consideration of wind speed and wind power output forecast error’s correlation, the probabilistic distributions of transmission line flows during tomorrow’s 96 time intervals are obtained using cumulants combined Gram-Charlier expansion method. The probability density function and cumulative distribution function of transmission lines on each time interval could provide scheduling planners with more accurate and comprehensive information. Simulation in IEEE 39-bus system demonstrates effectiveness of the proposed model and algorithm.展开更多
Along with the improvement of electrical equipment reliability,people’s unsafe behaviors and human errors have become one of main sources of risks in power systems.However,there is no comprehensive study on human fac...Along with the improvement of electrical equipment reliability,people’s unsafe behaviors and human errors have become one of main sources of risks in power systems.However,there is no comprehensive study on human factors and human reliability analysis in power systems.In allusion to this situation,this paper attempts to analyze the impact of human factors on power system reliability.First,this paper introduces current situation of human factors in power systems and the latest research progress in this field.Several analysis methods are proposed according to specified situations,and these methods are verified by some power system practical cases.On this base,this paper illustrates how human factors affect power system operation reliability from 2 typical aspects:imperfect maintenance caused by human errors,and impact of human factors on emergency dispatch operation and power system cascading failure.Finally,based on information decision and action in crew(IDAC),a novel dispatcher training evaluation simulation system(DTESS)is established,which can incorporate all influencing factors.Once fully developed,DTESS can be used to simulate dispatchers’response when encountering an initial event,and improve power system dispatching reliability.展开更多
Over the past decade,China has undertaken substation intellectualization of more than 2000 substation operations in three stages.Much experience has been achieved during this developmental period.In this paper,the sta...Over the past decade,China has undertaken substation intellectualization of more than 2000 substation operations in three stages.Much experience has been achieved during this developmental period.In this paper,the status of smart substation development in China is systematically presented,as well as future directions of the smart substation,such as adoption of the hierarchical protection and control system.展开更多
Phasor measurement units(PMUs)provide useful data for real-time monitoring of the smart grid.However,there may be time-varying deviation in phase angle differences(PADs)between both ends of the transmission line(TL),w...Phasor measurement units(PMUs)provide useful data for real-time monitoring of the smart grid.However,there may be time-varying deviation in phase angle differences(PADs)between both ends of the transmission line(TL),which may deteriorate application performance based on PMUs.To address that,this paper proposes two robust methods of correcting time-varying PAD deviation with unknown parameters of TL(ParTL).First,the phenomena of time-varying PAD deviation observed from field PMU data are presented.Two general formulations for PAD estimation are then established.To simplify the formulations,estimation of PADs is converted into the optimal problem with a single ParTL as the variable,yielding a linear estimation of PADs.The latter is used by second-order Taylor series expansion to estimate PADs accurately.To reduce the impact of possible abnormal amplitude data in field data,the IGG(Institute of Geodesy&Geophysics,Chinese Academy of Sciences)weighting function is adopted.Results using both simulated and field data verify the effectiveness and robustness of the proposed methods.展开更多
文摘Short-term power flow analysis has a significant influence on day-ahead generation schedule. This paper proposes a time series model and prediction error distribution model of wind power output. With the consideration of wind speed and wind power output forecast error’s correlation, the probabilistic distributions of transmission line flows during tomorrow’s 96 time intervals are obtained using cumulants combined Gram-Charlier expansion method. The probability density function and cumulative distribution function of transmission lines on each time interval could provide scheduling planners with more accurate and comprehensive information. Simulation in IEEE 39-bus system demonstrates effectiveness of the proposed model and algorithm.
基金supported by the State Key Program of National Natural Science Foundation of China (No.51537010)Zhejiang Provincial Natural Science Foundation (No.LZ14E070001)
文摘Along with the improvement of electrical equipment reliability,people’s unsafe behaviors and human errors have become one of main sources of risks in power systems.However,there is no comprehensive study on human factors and human reliability analysis in power systems.In allusion to this situation,this paper attempts to analyze the impact of human factors on power system reliability.First,this paper introduces current situation of human factors in power systems and the latest research progress in this field.Several analysis methods are proposed according to specified situations,and these methods are verified by some power system practical cases.On this base,this paper illustrates how human factors affect power system operation reliability from 2 typical aspects:imperfect maintenance caused by human errors,and impact of human factors on emergency dispatch operation and power system cascading failure.Finally,based on information decision and action in crew(IDAC),a novel dispatcher training evaluation simulation system(DTESS)is established,which can incorporate all influencing factors.Once fully developed,DTESS can be used to simulate dispatchers’response when encountering an initial event,and improve power system dispatching reliability.
基金National Natural Science Foundation of China under Grant 51120175001Key Project of Smart Grid Technology and Equipment of National Key Research and Development Plan of China under Grant 2016YFB0900600Science and Technology Project of State Grid Corporation of China under Grant GWKJ2013-005.
文摘Over the past decade,China has undertaken substation intellectualization of more than 2000 substation operations in three stages.Much experience has been achieved during this developmental period.In this paper,the status of smart substation development in China is systematically presented,as well as future directions of the smart substation,such as adoption of the hierarchical protection and control system.
基金This work was supported by the National Key Research and Development Program of China(2017YFB0902901)National Natural Science Foundation of China(51627811).
文摘Phasor measurement units(PMUs)provide useful data for real-time monitoring of the smart grid.However,there may be time-varying deviation in phase angle differences(PADs)between both ends of the transmission line(TL),which may deteriorate application performance based on PMUs.To address that,this paper proposes two robust methods of correcting time-varying PAD deviation with unknown parameters of TL(ParTL).First,the phenomena of time-varying PAD deviation observed from field PMU data are presented.Two general formulations for PAD estimation are then established.To simplify the formulations,estimation of PADs is converted into the optimal problem with a single ParTL as the variable,yielding a linear estimation of PADs.The latter is used by second-order Taylor series expansion to estimate PADs accurately.To reduce the impact of possible abnormal amplitude data in field data,the IGG(Institute of Geodesy&Geophysics,Chinese Academy of Sciences)weighting function is adopted.Results using both simulated and field data verify the effectiveness and robustness of the proposed methods.
