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 tool.展开更多
To debug automatic mechanical transmission（AMT） more quickly and accurately,an AMT-fault-diagnosis device is designed based on the ISO 15765 protocol,which adopts the flow control mechanism and has off-line diagnost...To debug automatic mechanical transmission（AMT） more quickly and accurately,an AMT-fault-diagnosis device is designed based on the ISO 15765 protocol,which adopts the flow control mechanism and has off-line diagnostics function.Requirements for the device are analyzed and diagnostic trouble code（DTC） is defined.Electrically controlled hardware with graphics display function and fault diagnostic software flowchart are designed based on the electronic control hydraulic AMT system.Bench and vehicle driving tests showethat the AMT-fault-diagnosis device can read and delete the fault message successfully with a stable performance.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 tool.
基金Sponsored by the National High Technology Research and Development Program of China("863"Program)(2006AA110115)
文摘To debug automatic mechanical transmission（AMT） more quickly and accurately,an AMT-fault-diagnosis device is designed based on the ISO 15765 protocol,which adopts the flow control mechanism and has off-line diagnostics function.Requirements for the device are analyzed and diagnostic trouble code（DTC） is defined.Electrically controlled hardware with graphics display function and fault diagnostic software flowchart are designed based on the electronic control hydraulic AMT system.Bench and vehicle driving tests showethat the AMT-fault-diagnosis device can read and delete the fault message successfully with a stable performance.
