Hitachi Energy Switzerland Ag

Abb Power Grids Switzerland Ag

General Electric Company

Hitachi Energy Ltd

Abb Schweiz Ag

Sachin Srivastava

Obbalareddi Demudu Naidu

Neethu George

Swaroop Gajare

A V Sai

Jianping Wang

Venkatesh Rajagopalan

Od Naidu

Nandkishor Kubal

Preetham Venkat Yalla

Vedanta Pradhan

Alexander James Pistner

Suresh Maturu

Matthew Everett Moore

Lijie Yu

Amit Purohit

Arulselvan G

Arulselvan Govindaraj

Sourabh Mehndiratta

Sandeep Pabbathi

Prabakaran Selvaraj

Raghavan Varadhan

Mayank Lalan

Naidu Obbalareddi Demudu

Fault detection in a shunt capacitor bank connected to a power system is described. Voltage and current measurements are obtained at a terminal of the shunt capacitor bank. An electrical parameter is calculated based on the voltage and current measurements, where the electrical parameter is an impedance angle or an active power. A difference between a first and a second value of the electrical parameter is calculated, based on which a fault is detected.

Fault detection in shunt capacitor banks

Fault detection during a power swing in a power transmission system is described. Voltage and current measurements are obtained for each phase at a terminal of the power transmission system. Based on measurements obtained, a value of change in an impedance angle for each phase-to-ground loop and each phase-to-phase loop for each sample of the voltage and current values is calculated, where the value of change in the impedance angle is a difference between impedance angles of two samples separated by a predetermined interval. The average values for change in impedance angle based on a predetermined number of values of change in the impedance angle for each phase-to-ground loop and each phase-to-phase loop is calculated. The average values are compared with a threshold range of change in impedance angle. Based on the comparison, a fault in one or more of the phase-to-ground loops or phase-to-phase loops is detected and classified.

Fault detection in a power transmission system

The invention relates to protection from faults in a power transmission system having two or more transmission lines. Travelling waves are detected from a signal obtained with a measurement equipment associated with a bus of the power transmission system. Arrival times of a first peak of a first travelling wave, a second travelling wave and a third travelling wave, are detected from the signal. A value for line length is calculated from the arrival times and propagation velocity of the travelling wave in the corresponding transmission line. The calculated value is compared with an actual length of the corresponding transmission line, for determining if the fault is an internal fault or an external fault. According to the fault being one of the internal fault and the external fault, a signal for controlling a switching device associated with the corresponding transmission line is generated.

Accelerated zone-2 protection for transmission lines

A method and device can be used with a power transmission line. Pre-fault voltage and current phasors and during-fault voltage and current phasors for each of first, second, and third terminals are determined based on disturbance records. Using an assumed faulted section, values for a propagation constant of each section, a surge impedance of each section, and a fault location parameter are computed. The computing is based on simultaneously solving pre-fault and during-fault objective functions for the assumed faulted section with the computed pre-fault and during-fault voltage and current phasors. The pre-fault and during-fault objective functions are formulated based on equating junction voltages determined from two of the terminals, conservation of charge at the junction, and equating fault location voltages determined from one terminal and the junction. The values determined for the propagation constant, the surge impedance, and the fault location parameter can be compared with predefined criteria.

Parameter free identification of fault location in multi-terminal power transmission lines

A device can be used with a power transmission system that includes three section that are connected at a junction, each section being from a corresponding. An input interface receives measurements of voltages and currents carried out at one or more of the first terminal, the second terminal and the third terminal or positive sequence voltage and current phasors obtained from the measurements of voltages and currents carried out at one or more of the first terminal, the second terminal and the third terminal. A phasor calculation module calculates positive sequence voltage and current phasors from the measurements of voltages and currents carried out at a terminal of the power transmission system. A fault locator obtains the fault location based on the section with the fault, the positive sequence voltage and current phasors obtained for each terminal, and the positive sequence line impedance parameters of each section.

Fault location in multi-terminal tapped lines

The invention provides an Intelligent Electronic Device (IED) and a method for locating a fault in a power transmission line with the IED. The method comprises measuring arrival times of a first, second and third peak of a travelling wave, using measurements obtained with one or more measurement equipment connected with the power transmission line. The method further comprises generating two or more initial estimates for the location of the fault, estimating time of initiation of the travelling wave, and estimating an arrival time of the third peak. The estimated arrival time of the third peak is compared with the measured arrival time of the third peak, to select an initial estimate of the two or more initial estimates as the location of the fault.

Travelling wave based method for locating a fault in a transmission line and device therefor

A method and system is provided for locating a fault in a mixed power transmission line. The method is implemented by an Intelligent Electronic Device (IED) of the mixed line. The IED detects a travelling wave from one or more signals received from one or more measurement equipment. Thereafter, the IED identifies a line section with the fault, and generates two or more estimates for the location of the fault based on a time difference between arrival of two peaks of the travelling wave, a velocity of propagation of the travelling wave in the line section identified with the fault, and a length of one or more line sections. The IED determines the location of the fault based on a comparison of each estimate with a threshold, wherein the threshold is estimated based on the one or more signals, equivalent source impedance of each source and total line impedance.

Method and system for locating a fault in a mixed power transmission line

The invention provides a method and device for fault section identification in a multi-terminal mixed line. The method comprises obtaining positive sequence voltage and current phasors from measurements of voltages and currents at each terminal of the mixed line. The method further comprises calculating a voltage phasor for each terminal, wherein the calculation of the voltage phasor for a first terminal is performed using at least the voltage and current phasors obtained for one of a second terminal and a third terminal, and the current phasor obtained for the first terminal. Thereafter, the method comprises determining a section of the mixed line having the fault, based on comparison of the calculated and obtained voltage phasors for each terminal. In addition, the method comprises controlling a switching device with a re-trip signal generated based on the determination of the section with the fault.

Method and device for fault section identification in multi-terminal mixed lines

Systems and methods for predicting a surge event in a compressor of a turbomachine are provided. According to one embodiment of the disclosure, a system may include one or more computer processors associated with the turbomachine. The one or more computer processors may be operable to receive a plurality of performance parameters of the compressor and analyze the plurality of performance parameters to determine corrected performance values of the performance parameters. Based at least partially on the corrected performance values, a compressor efficiency may be determined. The processor may be further operable to standardize the compressor efficiency for a standard mode of operation, ascertain historical performance data associated with the standard mode of operation, and analyze the compressor efficiency based at least partially on the historical performance data. Based on the analysis of the compressor efficiency, a surge event may be selectively predicted.

Predicting a surge event in a compressor of a turbomachine

Systems and methods for blade health monitoring are provided. According to one embodiment of the disclosure, a system may include a feature extraction module and an anomaly detection module in communication with the extraction module. The feature extraction module may be configured to continuously receive blade passing signal data associated with clearance of a blade and pre-process the blade passing signal data. Blade clearance feature data may be extracted from the blade passing signal data prior to transmission to the anomaly detection module. The anomaly detection module may be configured to normalize the blade clearance feature data received from the extraction module, analyze the blade clearance feature data to detect a shift in the clearance of the blade, and determine an abnormality of the blade based on the shift exceeding a predetermined shift threshold.

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Bengaluru, India

Sachin Srivastava