G-PST Research Agenda Research Questions within the Program: Select an option from the dropdown 1. What are the needs of a power system (to achieve security and good regulation) expressed in technology neutral form and how do these needs map to services that any resource, including IBR or synchronous machine, can provide? 2. For each service defined in (1), how feasible is it to provide from IBR, what “cost” does it add and what limitations exist on its magnitude and duration of service? What implications do these have for system operations? 3. What are the limitations of each IBR technology option to provide frequency control services and how do the various frequency services overlap and compete? 4. What design standards or dispatch guidance should be introduced to avoid instability (e.g., caused by PLL or other elements) in weak grids? This is a more widely drawn version of the question on minimum ratios of grid-forming to grid-following inverters. 5. What are the appropriate inverter capabilities and, consequently, control design methods for operation in grids with high percentage of IBR? Are standard configurations and combination of services helpful in simplifying operational decision making? 6. Are the black-box models (impedance-spectrum and binary code) favoured by manufacturers for disclosure sufficient for stability assurance and system design across all problem types? 7. What recommendations should be made for standard behaviours of IBR in certain frequency ranges for different power system conditions to aid system design? For example, should a contribution to damping be mandatory at certain frequencies? 8. What impedance requirements should be placed on IBR to suppress negative-sequence and low order harmonic currents? 9. How will protection systems need to change to accommodate high penetrations of IBR and what possible actions might an inverter take during a fault that would aid fault detection and location? 10. What is the future of frequency control as the synchronous generation fraction reduces? Might tightened or loosened frequency limits lead to a more reliable, secure, lower cost IBR-based power system? 11. At what point is it better to break from trying to replicate synchronous machine features and exploit the wider flexibility of inverters?
G-PST Research Agenda Research Questions within the Program: Select an option from the dropdown 12. What approaches can be taken to near real-time system modelling with large quantities of IBR that make design for system stability sufficiently accurate and still tractable? 13. What methods can be used for off-line and on-line monitoring tools for detecting incipient instabilities? What new capabilities are needed to address these limitations? 14. What type of on-line contingency and stability analyses should be conducted at changing levels of IBR? 15. What analytical tools and models should be provided to planners and operators for robust assessment of system performance? 16. What tools are needed for operational analysis of higher impedance grids? 17. What analytical methods and tools should be used to determine the appropriate mix and capabilities of Grid-Forming and Grid-Following inverters to mitigate low inertia conditions for a given power system? 18. What are the appropriate analytical methods and tools to determine – for a given power system – the extent to which very fast frequency response can substitute for inertia. Relatedly, what tools and methods are needed to effectively compose a mix of Δf and df/dt responses? 19. What tools and methods are needed to identify the best mitigation strategies for voltage-collapse problems under high IBR conditions? And how effective is IBR in recovering from deep voltage dips (bearing in mind lack of short-term overload current)?
G-PST Research Agenda Research Questions within the Program: Select an option from the dropdown 20. How can operators identify critical stability situations in real-time and optimize system security? 21. How can system operators get relevant real-time visibility and situational awareness of the state of the power system with increasing penetrations of IBR and DER? 22. How can system strength, inertia and limits of stable frequency range be monitored in real-time in high IBR systems? 23. What are the appropriate methodologies to visualize and interpret relevant information for improved decision support for fast real-time control actions? 24. What quantities must be monitored, screened, and validated in real-time to ensure that there will be adequate flexibility availability from uncertain system resources in the near-term? 25. How can control capabilities for IBR-based system assets (FACTS, Line Impedance adjusters, etc.) and network flexibility more generally be maximized to enhance reliability and/or reduce costs. 26. Are there sufficient flexibilities available in the near-term to compensate variations in load and generation (fast changes as well as long lasting extreme situations such as prolonged periods of no solar and wind)? 27. How do control rooms address uncertainties in weather conditions that impact loads and renewable energy output and rate of change (ramps)? How can probabilistic forecasting techniques be better incorporated into real-time operations? 28. How can data be best utilized to ensure system operations include the ability to detect and mitigate a range of uncertain disturbances? 29. What quantities must be monitored, screened and validated to ensure reliable service provision from aggregated flexibility resources in distribution systems, supporting stable system operation? 30. What type of digital architecture is necessary to enable the variety of software required to operate a control room in real-time, near real-time and in auto pilot mode? 31. How can grid topology be flexibly adapted at various operating conditions?’ 32. What is a suitable data architecture for DER monitoring & modelling? Once DER resources have been aggregated spatially and temporally, how should this information be provided to the control room? Can DER categories be developed that allow groupings based on their ensemble response to system level events? What is the appropriate data architecture required to monitor/predict and control DER in real-time? 33. What is the communication capability needed to support monitoring and control of DER? What is the suitability of existing communications infrastructure – in terms of reliability, latency, bandwidth, (cyber)security – relative to investing in a bespoke system? For DER control purposes, what 2-way communication protocols are necessary? 34. What are the relative merits of different control architectures for DER? What might an efficient distributed control architecture be for DER which: (1) makes use of appropriate device characterizations and real-time monitoring data; (2) accounts for practical constraints around device-level communication; and (3) accounts for heterogeneous subgroup controls of DER and various existing DSO/TSO control schemes? 35. What is the best way to integrate large data sets, streaming information, and historical system performance to create actionable operational insights? 36. How can the status (generation output, state of charge, etc.) of each key category of DER be monitored/estimated in real-time? What are appropriate DER categories and the appropriate spatial and temporal resolution to monitor DER effectively? What are the appropriate technical means of achieving this level of aggregation?
G-PST Research Agenda Research Questions within the Program: Select an option from the dropdown 37. What additional probabilistic planning methods and tools are necessary for planning a power system with a high share of IBRs and in particular, variable renewable energy resources? 38. What studies and metrics are required to identify long term scarcity of capacity to maintain reliability? 39. What additional methods and tools are necessary to incorporate resilience concepts and the ability to recover from adverse conditions considering uncertain future states into planning a power system with a high share of renewables? 40. What additional planning models and methods are needed to plan for various levels of uncertainty and no-regrets investments in a paradigm of increasing electrification and growing IBR and DER penetrations? 41. How should sufficient black-start capability and the performance and integrity of the protection system be modeled in long term reliability studies? 42. What features need to be added to long-term planning methods and studies to consider other reliability services in addition to traditional resource adequacy and deliverability? 43. How can system security be balanced against lower costs for operation and investment? 44. What studies and metrics are required to evaluate resource adequacy with hybrid plants (e.g. PV-plus-storage) and virtual power plants? 45. How do system operators adequately account for extreme events in planning studies, particularly those that impact the resources used in a high renewable energy future (wind, solar, demand side flexibility)? 46. What mechanisms are necessary to accurately model and account for DER in planning exercises to ensure a reliable power system is being planned? What data is necessary to accurately model various levels/paradigms of DER control, including influence on under frequency load shedding schemes? 47. What additional load and resource forecasting models are necessary to account for electrification of the transportation and building sectors? 48. What changes can be incorporated into the transmission planning process to accommodate new drivers of uncertainty in electricity demand (e.g., large growth due to electrification or low growth due to increased use of DER)? 49. What additional planning models and methods are needed to plan for a system that can withstand expected or unexpected lulls in the weather driving much of the resource mix, e.g., an extended wind drought? 50. What are appropriate aggregate DER models and methods for inclusion in transmission-level modeling? 51. What models and methods are necessary to quantify the need and requirements for long duration energy storage?
G-PST Research Agenda Research Questions within the Program: Select an option from the dropdown 53. How should the definitions of services for IBR dominated grids be structured? Can standard services and standard characteristics be defined that are reasonable for large and small IBR and across VRE, storage and demand response interfaces? 54. What methodologies can be employed to determine if strong/stiff voltage control services can be reliably provided through reactive power droop or active regulation? 55. What models and methods are necessary to quantify the ability of VRE to provide essential reliability services to the grid, and how do system operators quantify the value of these reliability services (for example, as an input to system-specific market/incentive design questions)? 56. What roles can offshore wind and HVDC clusters play in providing energy system flexibility? 57. How can system performance requirements be translated into reliable new technology solutions? 58. How can system operators quantify the transmission level service opportunities from DER? What are the practical and technical limitations to the reliable provision of various DER services? 59. How can transmission-level services provided by DER be valued? What DER transmission-level service valuation methodologies are best suited as a compromise between simplicity and full cost-reflectiveness?
Additional G-PST Research Agenda Questions Across the Entire Research Agenda: Select an option from the dropdown No response 1. What are the needs of a power system (to achieve security and good regulation) expressed in technology neutral form and how do these needs map to services that any resource, including IBR or synchronous machine, can provide? 2. For each service defined in (1), how feasible is it to provide from IBR, what “cost” does it add and what limitations exist on its magnitude and duration of service? What implications do these have for system operations? 3. What are the limitations of each IBR technology option to provide frequency control services and how do the various frequency services overlap and compete? 4. What design standards or dispatch guidance should be introduced to avoid instability (e.g., caused by PLL or other elements) in weak grids? This is a more widely drawn version of the question on minimum ratios of grid-forming to grid-following inverters. 5. What are the appropriate inverter capabilities and, consequently, control design methods for operation in grids with high percentage of IBR? Are standard configurations and combination of services helpful in simplifying operational decision making? 6. Are the black-box models (impedance-spectrum and binary code) favoured by manufacturers for disclosure sufficient for stability assurance and system design across all problem types? 7. What recommendations should be made for standard behaviours of IBR in certain frequency ranges for different power system conditions to aid system design? For example, should a contribution to damping be mandatory at certain frequencies? 8. What impedance requirements should be placed on IBR to suppress negative-sequence and low order harmonic currents? 9. How will protection systems need to change to accommodate high penetrations of IBR and what possible actions might an inverter take during a fault that would aid fault detection and location? 10. What is the future of frequency control as the synchronous generation fraction reduces? Might tightened or loosened frequency limits lead to a more reliable, secure, lower cost IBR-based power system? 11. At what point is it better to break from trying to replicate synchronous machine features and exploit the wider flexibility of inverters? 12. What approaches can be taken to near real-time system modelling with large quantities of IBR that make design for system stability sufficiently accurate and still tractable? 13. What methods can be used for off-line and on-line monitoring tools for detecting incipient instabilities? What new capabilities are needed to address these limitations? 14. What type of on-line contingency and stability analyses should be conducted at changing levels of IBR? 15. What analytical tools and models should be provided to planners and operators for robust assessment of system performance? 16. What tools are needed for operational analysis of higher impedance grids? 17. What analytical methods and tools should be used to determine the appropriate mix and capabilities of Grid-Forming and Grid-Following inverters to mitigate low inertia conditions for a given power system? 18. What are the appropriate analytical methods and tools to determine – for a given power system – the extent to which very fast frequency response can substitute for inertia. Relatedly, what tools and methods are needed to effectively compose a mix of Δf and df/dt responses? 19. What tools and methods are needed to identify the best mitigation strategies for voltage-collapse problems under high IBR conditions? And how effective is IBR in recovering from deep voltage dips (bearing in mind lack of short-term overload current)? 20. How can operators identify critical stability situations in real-time and optimize system security? 21. How can system operators get relevant real-time visibility and situational awareness of the state of the power system with increasing penetrations of IBR and DER? 22. How can system strength, inertia and limits of stable frequency range be monitored in real-time in high IBR systems? 23. What are the appropriate methodologies to visualize and interpret relevant information for improved decision support for fast real-time control actions? 24. What quantities must be monitored, screened, and validated in real-time to ensure that there will be adequate flexibility availability from uncertain system resources in the near-term? 25. How can control capabilities for IBR-based system assets (FACTS, Line Impedance adjusters, etc.) and network flexibility more generally be maximized to enhance reliability and/or reduce costs. 26. Are there sufficient flexibilities available in the near-term to compensate variations in load and generation (fast changes as well as long lasting extreme situations such as prolonged periods of no solar and wind)? 27. How do control rooms address uncertainties in weather conditions that impact loads and renewable energy output and rate of change (ramps)? How can probabilistic forecasting techniques be better incorporated into real-time operations? 28. How can data be best utilized to ensure system operations include the ability to detect and mitigate a range of uncertain disturbances? 29. What quantities must be monitored, screened and validated to ensure reliable service provision from aggregated flexibility resources in distribution systems, supporting stable system operation? 30. What type of digital architecture is necessary to enable the variety of software required to operate a control room in real-time, near real-time and in auto pilot mode? 31. How can grid topology be flexibly adapted at various operating conditions?’ 32. What is a suitable data architecture for DER monitoring & modelling? Once DER resources have been aggregated spatially and temporally, how should this information be provided to the control room? Can DER categories be developed that allow groupings based on their ensemble response to system level events? What is the appropriate data architecture required to monitor/predict and control DER in real-time? 33. What is the communication capability needed to support monitoring and control of DER? What is the suitability of existing communications infrastructure – in terms of reliability, latency, bandwidth, (cyber)security – relative to investing in a bespoke system? For DER control purposes, what 2-way communication protocols are necessary? 34. What are the relative merits of different control architectures for DER? What might an efficient distributed control architecture be for DER which: (1) makes use of appropriate device characterizations and real-time monitoring data; (2) accounts for practical constraints around device-level communication; and (3) accounts for heterogeneous subgroup controls of DER and various existing DSO/TSO control schemes? 35. What is the best way to integrate large data sets, streaming information, and historical system performance to create actionable operational insights? 36. How can the status (generation output, state of charge, etc.) of each key category of DER be monitored/estimated in real-time? What are appropriate DER categories and the appropriate spatial and temporal resolution to monitor DER effectively? What are the appropriate technical means of achieving this level of aggregation? 37. What additional probabilistic planning methods and tools are necessary for planning a power system with a high share of IBRs and in particular, variable renewable energy resources? 38. What studies and metrics are required to identify long term scarcity of capacity to maintain reliability? 39. What additional methods and tools are necessary to incorporate resilience concepts and the ability to recover from adverse conditions considering uncertain future states into planning a power system with a high share of renewables? 40. What additional planning models and methods are needed to plan for various levels of uncertainty and no-regrets investments in a paradigm of increasing electrification and growing IBR and DER penetrations? 41. How should sufficient black-start capability and the performance and integrity of the protection system be modeled in long term reliability studies? 42. What features need to be added to long-term planning methods and studies to consider other reliability services in addition to traditional resource adequacy and deliverability? 43. How can system security be balanced against lower costs for operation and investment? 44. What studies and metrics are required to evaluate resource adequacy with hybrid plants (e.g. PV-plus-storage) and virtual power plants? 45. How do system operators adequately account for extreme events in planning studies, particularly those that impact the resources used in a high renewable energy future (wind, solar, demand side flexibility)? 46. What mechanisms are necessary to accurately model and account for DER in planning exercises to ensure a reliable power system is being planned? What data is necessary to accurately model various levels/paradigms of DER control, including influence on under frequency load shedding schemes? 47. What additional load and resource forecasting models are necessary to account for electrification of the transportation and building sectors? 48. What changes can be incorporated into the transmission planning process to accommodate new drivers of uncertainty in electricity demand (e.g., large growth due to electrification or low growth due to increased use of DER)? 49. What additional planning models and methods are needed to plan for a system that can withstand expected or unexpected lulls in the weather driving much of the resource mix, e.g., an extended wind drought? 50. What are appropriate aggregate DER models and methods for inclusion in transmission-level modeling? 51. What models and methods are necessary to quantify the need and requirements for long duration energy storage? 52. How do system operators black start a system with very few (or no) synchronous machines? 53. How should the definitions of services for IBR dominated grids be structured? Can standard services and standard characteristics be defined that are reasonable for large and small IBR and across VRE, storage and demand response interfaces? 54. What methodologies can be employed to determine if strong/stiff voltage control services can be reliably provided through reactive power droop or active regulation? 55. What models and methods are necessary to quantify the ability of VRE to provide essential reliability services to the grid, and how do system operators quantify the value of these reliability services (for example, as an input to system-specific market/incentive design questions)? 56. What roles can offshore wind and HVDC clusters play in providing energy system flexibility? 57. How can system performance requirements be translated into reliable new technology solutions? 58. How can system operators quantify the transmission level service opportunities from DER? What are the practical and technical limitations to the reliable provision of various DER services? 59. How can transmission-level services provided by DER be valued? What DER transmission-level service valuation methodologies are best suited as a compromise between simplicity and full cost-reflectiveness?
