23rd November 2020 | 12:00 – 2:00pm
Manager, Operational Analysis and Engineering, AEMO
“Power system operation with high-share of grid-connected and distributed inverter-based resources”
Topic 1: Power system modelling: present and moving forward
This presentation will provide a brief overview of the inherent modelling differences between synchronous generation and asynchronous generation, how wide-area EMT models are increasingly required to provide a realistic representation of power system dynamics in a grid dominated by inverter-based resources, and how traditional RMS models are proving to be inadequate or overly optimistic when performing transient stability studies. Limitations of both RMS and EMT models will be discussed, along with an overview of the initiatives currently taking place to address the new challenges posed by the adoption of EMT models for transient stability analysis, and the perspective of international Independent System Operators on the issue.
Topic 2: New and emerging bulk power system security challenges
The generation mix across the National Electricity Market (NEM) of Australia is changing rapidly over the last few years. This increases the complexity of operating one of the longest power systems of the world and present unprecedented operational challenges due to increased penetration of inverter-based resources (IBR). Large update in transmission and distribution connected IBR often results into early retirement or mothballing of traditional synchronous generators which provide some of the system security services such as inertia, contribution to system strength, voltage and frequency control. With change in generation mix these services are required to be sourced from new technologies. The majority of IBR in the NEM are located in remote areas of the grid, typically far from load centres and conventional synchronous generators. Being in remote and weak part of the network a small reduction in system strength either during a planned or forced outage of a network element could manifest into system security issues.
This presentation will discuss some of the technical challenges associated with integrating large amount of IBR into relatively weak part of the network. The presentation will show real life example of emerging bulk power system security challenges and some of the solutions to address them.
Topic 3: New and emerging power system security challenges caused by distributed energy resources
Distributed PV is growing rapidly in the National Electricity Market (NEM), and minimum demand levels are reducing. South Australia is forecast to reach zero megawatts of operational demand in the next year or two, with enough distributed PV operating to meet the entire demand of the region. What will this mean for the operation of the power system? What measures need to be put in place to ensure we can continue to operate a secure and reliable power system? This presentation will cover AEMO’s investigations into power system operation in periods with low demand and high levels of distributed PV, discussing emerging power system security challenges such as distributed PV disconnection in response to transmission faults, the need for distributed PV curtailment capabilities to be able to maintain minimum levels of synchronous generating units online for system strength and inertia, and impacts on under frequency load shedding schemes.
Topic 4: System restoration: present and moving forward
This session will cover how AEMO prepares and implements restoration of the power system when a wide-scale blackout occurs in the NEM, including:
- The challenges associated with recovering from wide-scale blackouts.
- What AEMO currently has in place to assist with NEM system restoration, which needs to be in place well in advance of any blackout event.
- How AEMO is adapting system restoration to changes in the power system and generation mix.
Presenter 1: Sorrell Grogan, Principal Engineer, Australian Energy Market Operator
Sorrell Grogan is a principal engineer at the Australian Energy Market Operator. His areas of work include EMT model and platform development, System Restart Ancillary Service and major event analysis, and complex operational scenario evaluations. He developed the first wide-area EMT model to evaluate the events that led to the 2016 South Australian Black System event, and was a key member of the investigation team. Prior to joining AEMO in 2014, Sorrell worked in the private, government and education sectors in power electronics design and information technology. Sorrell has Bachelor and Masters by Research degrees from Monash University in Electrical and Computer Systems Engineering.
Presenter 2: Dr. Nilesh Modi, Principal Engineer, Australian Energy Market Operator
Nilesh is a Principal Engineer at the Australian Energy Market Operator (AEMO). At AEMO, Nilesh has worked across various teams at AEMO including National Planning, electricity market operations and Systems Capability. Nilesh has worked on number of key projects/documents published by AEMO, namely the review of the South Australian (SA) system black event, system strength assessments for South Australia, the review of under-frequency load shedding design for SA, the system integrity protection scheme for SA, system strength requirements and the inertia requirement methodology. He has been involved in investigating system incidents that have resulted in large disruptions across the National Electricity Market (NEM). Nilesh is actively involved in the IEEE Power and Energy Society and CIGRE, and have published articles in the area of system strength, inertia, and challenges associated with integration of IBRs. Nilesh is a senior member of the IEEE and also an adjunct research fellow at the University of Queensland, Australia. Nilesh received his PhD from the University of Queensland, where he was awarded the Dean’s Excellence Award for RHD Excellence. He is a recipient of ESIG’s energy excellent award.
Dr Jenny Riesz is a Principal at AEMO, leading a work stream on the operational integration of distributed energy resources (DER). Prior to this she conducted post doctoral research at the University of New South Wales on market design for 100% renewable power systems, and was a Principal in Climate Policy and Renewable Energy at ROAM Consulting. Her PhD is in physics.
Presenter 4: Cheryl Noronha, Senior Engineer, AEMO
Cheryl is a Senior Engineer in AEMO’s Operational Analysis and Engineering team, where she investigates extreme power system events and is currently focussed on the NEM system restart process and improvements in this area. Prior to this, when Cheryl joined AEMO in 2012, she worked within the Generator connections team, assessing new and modified generators for their technical capabilities. Cheryl has a Bachelor of Computer Science and Engineering, and a Master of Electrical Engineering.