The new renewable generators are typically of small size, situated in dispersed locations and often in proximity of the consumers. Their large-scale penetration is rapidly altering the electric power system’s hierarchical architecture which has evolved in last century around large, centralized, and often remotely located synchronous generating stations.
DERs can be designed to operate in-parallel with as well as in-isolation from the utility grid. By being close to the consumers, they contribute to reduction in transmission losses and local substation capacity. A cluster of DERs and consumers that are connected together, but isolated from the utility grid, form a MicroGrid. A localized MicroGrid can improve local supply resiliency after loss of key transmission or distribution supply facility (or facilities) to adverse weather or after a natural disaster. It can keep lights on until the connection to the grid is re-established. Besides providing environmental, economic, power quality, and reliability benefits, DERs and MicroGrids provide positive societal benefits because they bring an electric supply to remote rural communities where grid connections are not geographically or economically viable.
This course is dedicated to exploring new challenges and opportunities introduced by the distributed energy resource (DER) interconnections to the existing utility network. The course will identify new transmission protection methodologies and new distribution protection philosophies permitting safe and reliable DER operations either in-parallel to utility grid or in MicroGrid mode.
The primary objectives of the course are as follows:
- Expose participants to the new protection challenges from non-hierarchical electric system's architecture introduced by large scale penetration of DERs.
- Identify protection challenges of MicroGrid and new methodologies to overcome them.
- Identify potential risks of DER producing destructive resonant overvoltage and methods to prevent it from occurring.
- Introduce participants to non-universal, low magnitude, non-inductive and only positive sequence current response of the renewable inverter resource to both balance and unbalance short circuits.
- Expose participants to the new protection methodologies taking into dissimilarities between short circuit responses to conventional synchronous and renewable inverter resources.
- Introduce participants to new grid codes necessary as foot print of renewable inverter resources are becoming dominant in overall utility resource mix.
- Module 1: Distributed Energy Resources (DERs) and MicroGrids - Benefits and challenges
- Module 2: Fault current characteristics of inverter resources
- Module 3: MicroGrid protection with conventional resources
- Module 4: MicroGrid protection with mix of conventional and inverter resources
- Module 5: DER penetration in the distribution system - Protection challenges and mitigation
- Module 6: DER penetration in the transmission system - Protection challenges and mitigation
- Module 7: Impact of inverter resources on line protection systems
- Module 8: New protection schemes and new grid codes to mitigate impact of inverter resources
- Module 9: New challenges and mitigations of applying single-phase trip and reclose scheme with renewable resources
Principal Engineer/Manager, Protection and Control Planning Group, BC Hydro
Dr. Mukesh Nagpal is a Senior Member and Distinguished Lecturer of IEEE Power and Energy Society (PES), Adjunct Professor at University of British Columbia, a professional engineer in the Province of British Columbia, and Fellow of Canada Engineers. He is Chair of Working Group, “Impact of Inverter Based Resources on Utility Transmission System Protection”, sponsored by IEEE-PES Power System Relaying Committee.
He received the PhD and M.Sc. degrees in electrical engineering from the University of Saskatchewan, Saskatoon, SK, Canada. Currently, he is a Principal Engineer/Manager with the Protection and Control Planning Group within BC Hydro Engineering, Burnaby. He has more than 33 years of experience in electrical consulting, utility research and power system protection. Dr. Nagpal has written about 40 technical papers on power system relaying and contributed to several ANSI/IEEE sponsored standards or guides on relaying practices.
In 2016, Engineers and Geoscientists BC conferred Dr. Nagpal with its highest engineering honour, the R.A. McLachlan Memorial Award, for his exceptional leadership in developing practical and effective ways to connect renewables to the grid.
