To guarantee a reliable power supply,the expected operation of all the components in the power system is critical.Distance protection system is primarily responsible of isolating the faulty section from the healthy pa...To guarantee a reliable power supply,the expected operation of all the components in the power system is critical.Distance protection system is primarily responsible of isolating the faulty section from the healthy part for the grid.Failure in protection devices can result in multiple conflicting alarms at the power grid operation center and complex event analysis to manually find the root cause of the observed system state.If not handled in time,it may lead to the propagation of the faults/failures to the adjacent transmission lines and components.With availability of the synchronized measurements from phasor measurement units(PMUs),real-time system monitoring and automated failure diagnosis are feasible.With multiple adverse events and possible data anomalies,the complexity of the problem will be escalated.In this paper,a PMUbased algorithm is presented and discussed to detect the root cause of the failure in transmission protection system based on the observed state,e.g.multiple line tripping andbreaker failures.The failure diagnosis algorithm is further enhanced to come up with the fully functional version of the failure diagnosis tool,which is tailored for the cases in which the PMU anomalies are present.In the developed algorithm,the validity of the PMU data is critical.However,such causes as communication errors or cyber-attacks might lead to the PMU data anomalies.This issue is welladdressed in this paper and some major types of anomaly detection methods suitable for PMU data are discussed.Results show that the ensemble approach has some distinct advantages in data anomaly detection compared to the previously used standalone algorithms.Additionally,the enhanced failure diagnosis method is developed to clean the inaccurate data in case of the anomaly in measured voltage magnitudes.Finally,both original and enhanced versions of the tool are tested on 96-bus test system using the real-time OPAL-RT simulator.The results show the accuracy of the enhanced tool and its advantages over the primary version of the 展开更多
基金the National Science Foundation(NSF)for supporting this research projectthe help of OPAL-RT support team.
文摘To guarantee a reliable power supply,the expected operation of all the components in the power system is critical.Distance protection system is primarily responsible of isolating the faulty section from the healthy part for the grid.Failure in protection devices can result in multiple conflicting alarms at the power grid operation center and complex event analysis to manually find the root cause of the observed system state.If not handled in time,it may lead to the propagation of the faults/failures to the adjacent transmission lines and components.With availability of the synchronized measurements from phasor measurement units(PMUs),real-time system monitoring and automated failure diagnosis are feasible.With multiple adverse events and possible data anomalies,the complexity of the problem will be escalated.In this paper,a PMUbased algorithm is presented and discussed to detect the root cause of the failure in transmission protection system based on the observed state,e.g.multiple line tripping andbreaker failures.The failure diagnosis algorithm is further enhanced to come up with the fully functional version of the failure diagnosis tool,which is tailored for the cases in which the PMU anomalies are present.In the developed algorithm,the validity of the PMU data is critical.However,such causes as communication errors or cyber-attacks might lead to the PMU data anomalies.This issue is welladdressed in this paper and some major types of anomaly detection methods suitable for PMU data are discussed.Results show that the ensemble approach has some distinct advantages in data anomaly detection compared to the previously used standalone algorithms.Additionally,the enhanced failure diagnosis method is developed to clean the inaccurate data in case of the anomaly in measured voltage magnitudes.Finally,both original and enhanced versions of the tool are tested on 96-bus test system using the real-time OPAL-RT simulator.The results show the accuracy of the enhanced tool and its advantages over the primary version of the
文摘就一起储能设备投入引起直流配电网保护误动事件的分析,指出储能设备的投入可能在直流配电网中产生较大的冲击电流。分析了冲击电流产生的原因及其影响因素,提出在储能设备投入时串入电阻型超导限流器(resistive-type superconducting fault current limiter,R-SFCL),可起到限制储能支路冲击电流的作用。利用PSCAD/EMTDC仿真软件对直流配电网储能设备投入情况进行仿真分析,验证了储能支路的电流变化特征以及所提限流方法的有效性。