公开(公告)号：US10444272B2

公开(公告)日：2019-10-15

申请号：US15701221

申请日：2017-09-11

Applicant: ABB Schweiz AG

Inventor： Kai Liu ,  Youyi Li ,  Jianping Wang

IPC: G01R31/08 ,  H02J13/00 ,  H02H7/26

Abstract: An objective of the application is to provide a method for detecting a disturbance in a power system within a digital substation and an apparatus using the same. The method includes: sensing electrical parameters at an end of a transmission line; sampling the sensed electrical parameters; extracting traveling-wave information from high frequency component of the samples using a signal processing method; and if the extracted traveling-wave information indicating occurrence of the disturbance, transmitting the extracted traveling-wave information to an intelligent electronic device of the digital substation from a merging unit or non-conventional instrument transformer of the digital substation. As compared with the amount of the sample data of the sensed electrical parameters, the amount of the data representing the extracted traveling-wave information is reduced. Thus the extracted traveling-wave information can be transmitted via a data link with a relatively narrow bandwidth, such as the process bus under standard IEC 61850.

公开(公告)号：US20190296543A1

公开(公告)日：2019-09-26

申请号：US16440236

申请日：2019-06-13

Applicant: ABB Schweiz AG

Inventor： Kai Liu ,  Jianping Wang ,  Youyi Li

IPC: H02H7/26 ,  G01R31/02 ,  H02H1/00

Abstract: A method for detecting fault in a power transmission line of a power transmission system and protection system using the same. The method includes: obtaining a system parameter of the power transmission system, adjusting protection reachability of a fault detecting element based on the obtained system parameter such that the adjusted protection reachability of the fault detecting element is applicable to a predetermined protection range, identifying whether there is an internal fault occurring on the transmission line using the adjusted fault detecting element, and generating a fault detection decision signal indicating the identified fault. If the predetermined protection range is desirable for the fault detecting element, its protection reachability may be adjusted in consideration of the influence imposed by the SIR such that the reach point of the adjusted fault detecting element can be extended to approach the end of the predetermined protection range. Consequently, the influence on its accuracy by various SIR values can be taken into account and accordingly the fault detecting solution can remove substantial errors as a result thereof.

公开(公告)号：US20180024183A1

公开(公告)日：2018-01-25

申请号：US15701221

申请日：2017-10-16

Applicant: ABB Schweiz AG

Inventor： Kai Liu ,  Youyi Li ,  Jianping Wang

IPC: G01R31/08 ,  H02H7/26

CPC classification number: G01R31/085 ,  G01R31/086 ,  G01R31/088 ,  H02H7/265 ,  H02J13/00 ,  Y04S10/522

Abstract: An objective of the application is to provide a method for detecting a disturbance in a power system within a digital substation and an apparatus using the same. The method includes: sensing electrical parameters at an end of a transmission line; sampling the sensed electrical parameters; extracting traveling-wave information from high frequency component of the samples using a signal processing method; and if the extracted traveling-wave information indicating occurrence of the disturbance, transmitting the extracted traveling-wave information to an intelligent electronic device of the digital substation from a merging unit or non-conventional instrument transformer of the digital substation. As compared with the amount of the sample data of the sensed electrical parameters, the amount of the data representing the extracted traveling-wave information is reduced. Thus the extracted traveling-wave information can be transmitted via a data link with a relatively narrow bandwidth, such as the process bus under standard IEC 61850.

公开(公告)号：US20190271730A1

公开(公告)日：2019-09-05

申请号：US16418105

申请日：2019-05-21

Applicant: ABB Schweiz AG

Inventor： Kai Liu ,  Jianping Wang ,  Youyi Li

IPC: G01R31/02 ,  H02H7/26 ,  H02H1/00

Abstract: A method for detecting fault direction of a transmission line of an AC power system and a control system using the same. The method includes sampling current values and voltage values at one end of the transmission line for a series of time points; computing instantaneous voltage values at compensated point on the transmission line from the current value samples and the voltage value samples based on a time domain lumped parameter differential equation for the transmission line for the series of time points; recording the current value samples and the computed instantaneous voltage values at the compensated point; computing at least one voltage fault component each using the recorded computed instantaneous voltage values for at least the at least two of the series of time points; identifying the fault direction in consideration of the at least one computed voltage fault component and the at least one computed current fault component; and generating a fault direction signal indicating the identified fault direction. Where a fault directional element is designed using the voltage fault components at the compensated point, it will work well for the AC power system with strong power source.

公开(公告)号：US20190072603A1

公开(公告)日：2019-03-07

申请号：US16174701

申请日：2018-10-30

Applicant: ABB Schweiz AG

Inventor： Kai Liu ,  Jianping Wang ,  Youyi Li

IPC: G01R31/02 ,  H02H3/16

Abstract: A method, control system and protective relay are provided for detecting faulted phases of transmission lines in an AC power system. The method includes sampling electric signals at one end of the transmission lines at a series of time points; computing instantaneous voltage values of electric signals at compensated points on the transmission lines from the values of the sampled electric signals based on a time domain lumped parameter differential equation for the transmission lines for the series of time points; recording the computed instantaneous voltage values of the electric signals; computing fault component or sudden-change of the instantaneous voltage values of the electrical signals; detecting the faulted phases or fault types by comparing the calculated fault component of the instantaneous voltage values at the preset compensated points; and generating signals indicating the faulted phases of fault types.

公开(公告)号：US09899830B2

公开(公告)日：2018-02-20

申请号：US14770240

申请日：2013-04-07

Applicant: ABB Schweiz AG

Inventor： Youyi Li ,  Kai Liu ,  Ivo Brncic ,  Zhanpeng Shi

IPC: H02H9/02 ,  H02H3/28 ,  H02H3/00 ,  H02H7/045

CPC classification number: H02H9/02 ,  H02H3/006 ,  H02H3/28 ,  H02H3/283 ,  H02H7/045

Abstract: The present invention discloses a method for detecting a fault and a current differential protection system thereof. The method for detecting fault includes calculating fault component currents, calculating an operate current and a restraint current of all terminals, and adjusting an operate level by adapting an operate-restraint characteristic according to a fault component. The method has very small operating area for external faults, which makes the method very reliable even for the case with serious CT saturation. A very big operating area for internal faults makes the method very sensitive for internal faults even for a heavy load and high resistance fault.