A.I. in Power Systems Alarm Processing
Transcription
A.I. in Power Systems Alarm Processing
A.I. in Power Systems Alarm Processing Michael Nagy – PhD Scholarship Student michael.nagy@nicta.com.au Affiliation: NICTA Optimisation Group, NICTA Machine Learning and Australian National University Supervisors: Prof. Sylvie Thiébaux, Adj/Prof. Hanna Suominen, Dr. Alban Grastien - Senior Researcher. Email: firstname.lastname@nicta.com.au Introduction and Background Timed Hybrid Automaton for Critical Alarms The Electricity Industry and its provision of power is ubiquitous. For a High Voltage Power System (HVPS) to function safely and efficiently, a number of automated systems are required to function in unison. One such system is the Alarm System that notifies human operators of status and condition of the Power System. A power system in a metropolitan area can deliver thousands of alarms per day that can overwhelm human operators. This is an alarm stream which, in periods of high inflow, becomes an ’Alarm Avalanche’ or ’Alarm Flood’ and has been around for 25 years since the advent of the Supervisory Control and Data Acquisition System (SCADA). Much of the research has been conducted in critical alarm conditions (3%) with very little on the non-critical alarm conditions (97%). This Thesis will address both conditions using an Finite State Timed Hybrid Automaton, Machine Learning, Natural Language processing and Information Visualisation. In this Thesis, critical alarms are defined as alarms produced by the HVPS. In our novel approach, the Finite State Timed Hybrid Automaton uses the alarms generated by the HVPS to identify critical alarms and create a casual inference graph. A critical alarm, if not attended to, will result in disintegration and ultimately failure of power system electrical apparatus. Figure 3: Timed Hybrid Automaton Machine Learning for Non-Critical Alarms Figure 1: Alarm Breakdown: Critical to Non-Critical Alarms Problem to Solve The problem is stated as: ’How to use Artificial Intelligence (A.I.) methodologies to assist human operators to digest and respond to the significant volume of power system alarm events given critical and non-critical power system conditions.’ A non-critical alarm is the complement of a critical alarm. Natural Language Processing, Machine Learning and Information Visualisation methods process the non-critical alarms generated by a HVPS. In our novel approach, the edit distance of alarm messages are related to the same device and location; Conditional Random Fields to recognise the named entities (e.g., device name, geographic location, device status, data and time); information visualisation to produce cross-sectional summaries (i.e., geospatial maps) and longitudinal trends of the incoming alarm stream with an associated probability. A significant portion of research for solving this problem has been based on dealing with critical alarms which, from empirical evidence, is about 3% of the total alarm volume. The purpose of this Thesis is to find a complete solution for 100% of alarms generated in order to support human operators’ situational awareness. Figure 2: Breakdown of Alarm Sequence Figure 4: Alarm Geospatial Mapping Research Excellence in ICT Wealth Creation for Australia