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This paper presents a new relay for the protection of power transmission systems by using the global positioning system (GPS) and the transient polarity comparison techniques, the positional polarity comparison relay. A specially designed protection relay detects the fault generated high frequency current transient signals and records the polarity of the transient signal and the time instant corresponding...
The performance of the negative sequence pilot protection (NSPP) is less deteriorated by the phase-ground shunt capacitance since the negative sequence current loops in phase-phase lines. Hence NSPP is a good candidate for the main protection in UHV lines with the special characteristic of larger charging current. But as we all known, NSPP is not suit to the open-phase operations in transmission line,...
This paper presents a new protection scheme for high-speed protection of transmission lines, the Integrated Positional Protection scheme. The concept of integrated protection is firstly introduced, in which a centralized protection relay provides the protection for multiple transmission lines. The proposed scheme is based on a specially integrated relay unit, which is installed at each substation...
The fast development in both microprocessor and transducer technologies has enabled fault detection techniques to be considered which were impractical in the past and encouraged interest in the utilization of fault generated transients for protection. This paper presents an integrated approach for high-speed protection of transmission lines. The technique uses a fault transient detector unit at the...
The paper presents extensive simulation studies with respect to a typical EHV transmission line systems, the proposed protection technique is able to give correct responses for various system and fault condition. Furthermore, the protection scheme offers not only fast protection for individual line section, but also integrated protection for all lines connected to the substation, therefore it could...
This paper presents a novel relay for power transmission line systems, which is based on a combination of positional and boundary protection principle. The relay installed at a substation is responsible for the protection of the transmission lines associated with the substation. The relay is able to offer fast trip for any fault on its protected line sections without the need for communication link...
The impedance algorithm in distance protection for high voltage (HV) and extra high voltage (EHV) lines, although neglecting the influence of shunt capacitance, is able to produce satisfactory performance. However, the accuracy of the algorithm is significantly reduced when applying to ultra high voltage (UHV) lines due to the larger P.U. line shunt capacitance and longer transmission radius. Therefore,...
This paper presents a new integrated protection relay and its associated scheme for distributed generation systems. In the scheme, an integrated relay is responsible for the protection of both line sections associated with the substation bus. Based on conventional directional overcurrent protection technique, the basic principle of the new relay is to determine whether a fault is on the protected...
This paper presents the design of new real time digital simulator (RTDS) based novel relay test systems. The background of the developments in protection relays and their associated technologies, such as optical transducers and IEC 61850, are introduced. The new developments in RTDS systems are described. It is shown that the recent developments in transducers and communication technology will have...
This paper presents a new integrated protection scheme for transmission lines. The concept of the integrated protection is firstly introduced, in which a centralized protection system provides the protection of multiple power plant or a substation. A total integrated protection scheme based on current differential protection techniques is further described. In the proposed scheme, the specially designed...
This paper presents a novel integrated protection scheme for distribution lines based on Transient Polarity Comparison technique. In the proposed scheme, the specially designed interface units are installed at each substation and connected to the CTs on every line associated to the busbar. The unit converts the measured signals to optical format and sends to the central protection relay through a...
Cascading overload trip due to lack of transmission section protection is an important reason of large-scale blackout. This paper illustrates the meaning of transmission section and points out that the objective of transmission security protection is to maintain its integrality and transmission capacity, and to avoid cascading overload trip. In addition, the implement condition and key technology...
This paper presents a new technique for the protection of power transmission systems by using the global positioning system (GPS) and fault generated transients, the integrated positional protection technique. The technique is based on the detection and processing of fault generated high frequency transient signals, in which a centralized protection relay provides the protection of multiple transmission...
The precision of impedance fault location algorithm is deteriorated by the extremely large shunt capacitance in UHV line. And the traditional improved ways are all invalid caused by the nonlinearity of measurement impedance in relay and the frequent variations of operation modes in UHV system. In response to this question, a novel impedance fault location algorithm is proposed for phase faults. It...
This paper presents a novel pilot wire differential protection scheme for distribution systems. The concept and principle of conventional pilot wire differential protection is introduced first. Then, several kinds of numerical differential protection schemes using pilot wires as communication channels are discussed in the paper. A novel numerical protection scheme is further described, in which conventional...
This paper first outlines an advanced integrated protection scheme based on the latest developments in protection and communication technologies. The paper then gives a description of the communication networks and systems in substations based on the IEC61850 standard. The paper emphasizes the construction of the information model and the analysis of communication capacity of IEC61850 for the integrated...
This paper presents a novel integrated protection scheme for distribution networks using the transient polarity directional comparison technique. The technique is based on the detection and processing of fault generated transient current signals, in which specially designed protection relays are installed at each substation of a distribution network. The transient detection unit of the relay detects...
This paper presents an integrated boundary protection scheme for power transmission line systems. The scheme combines the latest developments in two areas of power system protection, the transient based protection and the integrated protection. In the proposed scheme, an integrated relay based on boundary protection principle installed at a substation is responsible for the protection of all transmission...
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