School of Electrical and Electronic Engineering
The University of Adelaide
Adelaide, Australia
e-mail : mustarum@eleceng.adelaide.edu.au
2 Rastko Zivanovic
School of Electrical and Electronic Engineering
The University of Adelaide
Adelaide, Australia
e-mail : rastko@eleceng.adelaide.edu.au
Abstract—Data recorded during faults in transmission network are used by control centre personnel to analyze the protection system and to decide on remedial actions that will restore normal network operation as fast as possible. The increasing number of installed digital fault recorders (DFRs) and other intelligent electronic devices (IEDs) in substations has resulted in a large number of fault records to be analyzed by the power system engineer. Manual analysis of these records is both timeconsuming and complex and for these reasons, many records may not be examined and much of their potential value would be lost. Determining how to make effective analysis of these records is a challenge being faced by many power utilities. The main purpose of this paper is to propose enhancements to the manual investigation of faults and disturbances that currently are performed by engineers in the Indonesian power utilities. In this paper, a new software framework for Automated Fault Analysis is proposed based on Application Service Provider (ASP) technology, which has lately received special attention in the development of distributed systems. Demonstrations of the following services currently implemented in the ASP are presented: signal pre-processing, fault analysis and protection performance analysis. The fault scenario from South Sulawesi transmission system is investigated to test the feature of the services
Keywords: Automated Fault Analysis; Application Service Provide
I. INTRODUCTION
The objectives of every electric power utility are to maintain network integrity and stability throughout, and to
promote higher reliability of power supply to customers without interruption. To support these objectives, many attempts are made to enhance automatic protective relaying systems. One of the attempts is to improve the quality of information available to human operators or controllers in the control centers via automated fault analysis. The analyses rely on data recorded during disturbances. In recent years, the
volume of recorded data has increased due to the increasing number of recording devices in substations. The investigation and management of disturbance records takes considerable time and will require skilled personnel. Manual analysis of these records is time-consuming and very complex. To enhance such analysis we are proposing use of standardized automated fault analysis services provided via Application Service Provider (ASP). The services could be used in automated way and in conjunction with the rule-based system that captures knowledge of experienced investigation engineers [1]. Individual services can be used for semiautomatic analysis when we follow step-by-step investigation procedure and solve all required tasks using the investigation services. This approach can be followed when analyzing very complex disturbances or to verify result of the automated analysis. This paper describes motivations, some requirements and possible solutions for an investigation of fault and disturbances in the Indonesian power utility.
II. INDONESIAN POWER UTILITY BACKGROUND
Since 2002 Indonesian power utility is operating Supervisory Control and Data Acquisition (SCADA) system at South Sulawesi transmission system and has introduced Intelligent Electronic Devices (IEDs) such as Digital Protective Relays (DPRs) and Digital Fault Recorders (DFRs) on all transmission feeders. There are several types of data that can be produced by IEDs such as: oscillography data, setting data, fault data and event record data [2]. The analysis of the data coming from these IEDs can provide valuable information to controllers with respect to the operating of power system. In case of fault occurs in power system, the SCADA system will get information on the status of that line if the line is disconnected due to protection action, but there is no information available to describe the issue. Control centre personnel who are in charge of controlling circuit breakers via SCADA system need more detailed information about the fault and performance of circuit breakers and protection system to make decision on how to restore the line into service. The protection engineer will analyze the event and give to the system operator the necessary information related to the fault. In this investigation the protection engineer will mostly use data available in relays and other IEDs. In the Indonesian power utility, the protection engineer has to go to the substation to upload all disturbance records to their laptop and investigate these records using suitable software that can
be converted to Common Format for Transient Data Exchange (COMTRADE) [3]. COMTRADE is an IEEE standard for digital data that commonly used by protection engineer to investigate faults and disturbances. When several engineers in an organization with different experience are investigating events it is most likely that different standards and tools are being used. Thereby the possibility to have very different
disturbance reports is high and in some cases might lead to even false conclusions. This situation can be clearly prevented if all investigation engineers follow the same procedure and use the same services that are organized and provided via ASP. The proposed new approach would be through automatic or semi-automatic use of the investigation services provided through an ASP. The ASP based fault and disturbance
investigation is a solution that will speed up the investigation process in order to find out the root cause of faults and disturbances and provide a report to control centre personnel in timely manner. One advantage of ASP-based investigation is that will insure a more consistent analysis of faults .
III.. CONCLUSION
The proposal for automated fault analysis in the Indonesian power utility has been described in this paper. Several services are proposed in order to enhance manual analysis that currently implemented by protection engineers. A case study of South Sulawesi transmission system is discussed with the analysis results.
Authorized licensed use limited to: UNIVERSITY TEKNOLOGI MALAYSIA. Downloaded on July 31,2010 at 17:11:49 UTC from IEEE Xplore. Restrictions apply.
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