Power System Monitoring Using Wireless Substation and System- Wide Communications Mobile Agent Part Mladen Kezunovic (P.I.) Xiangjun Xu Texas A&M University PS ERC PSerc Review Meeting College Station, November 7, 2002

PS ERC 2 Outline  Introduction  Major Results  Maintenance Scheduling  Circuit Breaker Monitoring and Maintenance  Agent-Oriented Approach for Workflow Management  Publications  Conclusions

PS ERC 3 Introduction System wide communications are aimed at power system monitoring and maintenance applications MERL’s Concordia mobile agent software has been applied to solve system wide communication problems Project was initiated in September 2000 and ended in August 2002

PS ERC 4 Statement of Work Study of the mobile agent software and comparison with other distributed systems Study of the scenarios for application of the mobile agent software Agent-oriented approach applied in the maintenance process Documenting the research results

PS ERC 5 Application Scenario Mobile Agent Server Signal AnalysisExpert System Substation data concentrator DatabaseRule Base Report Data files Data Acquisition Unit Maintenance Crew Enterprise Maintenance System ISO

PS ERC 6 Requirements on Communication Method   Working on distributed information among multiple entities (both geographically and organizationally)   Working on heterogeneous systems   Working on low-bandwidth networks   Supporting user level access control   Providing user friendly interfaces

PS ERC 7 Concordia Mobile Agent Software A cross-platform middleware software implemented in Java. It supports a wide variety of devices, from high-end servers to hand held computers. Mobile agents travel to the information source and reduce network bandwidth usage. It provides many useful functions to simplify development.

Major Results

PS ERC 9 Maintenance Scheduling in Deregulated Environment The diverse ownership of the equipment may lead to contradictory goals Intensive communication and coordination among market participants are required.

PS ERC 10 Applying Mobile Agent Software for Maintenance Scheduling The original scheduling problem is decomposed into two sub-problems. Mobile agent travels between ISO and GENCO, exchanges data until a solution is obtained. GENCO Master problem (IP) ISO Sub-problem (LP) Initial solutionCut

PS ERC 11 Benefits Working on heterogeneous systems Possessing more flexible system structure Providing a solution for utilities who do not want to expose their data to other entities

PS ERC 12 Circuit Breaker Monitoring and Maintenance A prototype system utilizing Concordia for CB applications has been built. The system has been integrated with the CB monitoring software.

PS ERC 13 User Interface – Example #1 (Retrieve Circuit Breaker Info)

PS ERC 14 User Interface – Example #2 (Display COMTRADE file)

PS ERC 15 Agent-Oriented Approach for Workflow Management Agent sensors subscribing to events of interest Agent effectors callback functions Inference Engine Rule base External events Facts Callback functions Actions

PS ERC 16 Benefits of Agent-Oriented Approach Proactive software agents rather than just reactive Better assisting the maintenance crew Higher level abstraction and encapsulation Better software structure

PS ERC 17 X. Xu, M. Kezunovic, “Mobile Agent Software Applied in Maintenance Scheduling”, NAPS 2001, X.Xu, M.Kezunovic, D.Wong, "Agent-Oriented Approach to Work Order Management for Circuit Breaker Maintenance", IEEE PES Summer Meeting 2002 M.Kezunovic, X.Xu, D.Wong, "Improving Circuit Breaker Maintenance Management Tasks by Applying Mobile Agent Software Technology", IEEE T&D Conference 2002, Asia Pacific Publications

PS ERC 18 Conclusions A prototype system utilizing Concordia mobile agent software for circuit breaker maintenance has been built. Interfacing between the real time CBM system and agent-based system for system- wide communications has been implemented Real application scenarios provided by utilities are still not available. Current focus has shifted to investigating the agent-oriented approach.