The increasing penetration of inverter-based resources and HVDC interconnections have created unfavourable dynamic interactions, oscillations and low inertia related stability issues. With the planned continuous growth of inverter-based resources into the system, it is essential to develop real-time modelling and simulation studies for fundamental understanding and mitigation strategies of various types of oscillations.
This project aims to develop a real-time simulation of a region of GB power system in both phasor and EMT modes for transient stability assessments. It investigates when and where to use the phasor mode and EMT mode simulations for a given system condition and provide real-time simulation of the grid in that region for system stability and security and identification of stability risks.
Benefits
The GB power system is transforming into a lower inertia system and facing the decline in short circuit level. The ESO needs to ensure that the sophisticated methodologies and simulation models under consideration are accurate and robust before incorporating them into the decision-making when maintaining system stability. Inaccurate simulation model or inappropriate use of a model in the wrong time and region carries tremendous technical risk, as well as significant business risk if making incorrect judgments based on it. This project investigates the real-time simulation phasor-EMT models to utilise the advantages of both simulation modes to increase the stability and reducing the uncertainties involved in the modelling and stability studies.
Learnings
Outcomes
The WP1 deliverables have been summarized below:
- HYPERSIM simulation model of South Coast power system with different technologies (LCC and VSC-HVDC lines) for offline, HIL, and real-time simulation purpose
- Report on offline simulation of HYPERRSIM model and PSCAD model of South Coast power system.
- Report on feasibility study of HIL-based experiments of HYPERSIM model of South Coast power system.
- A full report has been delivered on completion of WP1 tasks earlier described
WP2 deliverables have been summarized below:
- Adjusted PSCAD version of South Coast power system model for use in ePHASORSIM environment.
- South Coast power system input/output pin data file for offline, HIL, and real-time simulation purposes.
- ePHASORSIM simulation model of South Coast power system for offline, HIL, and real-time simulation purpose.
- Report to be delivered on offline simulation of ePHASORSIM model and PSCAD model of South Coast power system.
- Report to be delivered on feasibility study of HIL-based experiments of ePHASORSIM model of South Coast power system.
- A full report will be delivered on completion of WP2 tasks earlier described.
Lessons Learnt
In completing WP1 and most of WP2, the University of Warwick explored how we could model the GB network in the level of detail needed for EMT analysis. We started with our existing analytical model for stability analysis and added layers of complexity to make it EMT compatible. Having found that it was possible to capture EMT data in this way without affecting the original south coast network data, we’ve entered phase two of the project to develop our model further and validate its findings.
Next, we will be exploring the challenges and opportunities of using our model to create a tool to measure stability in real time – to for example help us, understand what kind of computational power would be required, whether it could be used effectively for regional grid level stability analysis, and if we could calculate EMT information quickly enough for the Control Room to use it for critical network analysis.
The last part of the project will be to develop a framework and standards for EMT analysis of stability, which will set the groundwork for the future development of a tool to provide real time EMT analysis and reporting.
