Simulation and modeling of smarter large power grids

1. Simulation and modeling of smarter large power grids Omar Saad, Researcher IREQ/Hydro-Québec ADVANCED ENERGY 2012 30-31 Octobre 2012, New York, NY, USA

2. Modern (Future) power systems • Increasingly complex transmission and distribution systems • Evolution and upgrading of existing systems allowing to increase the penetration of renewable energies and to elevate security and flexibility levels • Delivery of greener power • Large scale integration of renewable generation • Central and distributed generators, microgrids • Proliferation of HVDC systems • Smart Grids • Huge needs in information and data for the operation and planning of power systems

3. Large scale integration of renewable generation • Deployment of intelligent controls, computer applications and communications • Smart technologies for the interconnection of renewable energy generators in wide geographic areas • Management of distributed resources • Power electronics application for: control and variability • Sophistication of analysis methods

4. Trends and challenges • Simulation and analysis of super large networks with wideband models • Electromagnetic and electromechanical transients • Simulation of super distribution grids (Smart network) • Challenges • Data and data portability between power system applications • Visualization and analysis of huge systems • Parallel computations • Real-time computations • Online analysis • Unification of simulation methods and environments • Multi-domain simulations

5. Simulation of very large systems: Hydro-Québec Network in EMTP-RV • 1100 lines • 296 3-ph transformers • 532 loads • 7 SVC • 32 Synchronous Condenser • 99 SM

6. EMTP model of Gaspésie system:Integration of wind generation

7. Hydro-Québec • Pioneered important research and development works on advanced simulation methods for large scale and complex power systems • Advanced real-time simulation methods • Advance off-line simulation methods • Sophisticated utilization of simulation tools for transmission and distribution network studies • Integration of wind generation: 4 GW by 2015 • Based on detailed studies of electromagnetic and electromechanical transients • At Hydro-Québec (TransÉnergie) the frequency range of simulation models has been constantly increasing with increasing computer speed, improved models and numerical performance.

8. Real-Time simulator • Capability to solve power systems quickly enough to produce outputs synchronized with the real-time clock • A second of simulation = 1 second of clock time when testing equipment • A real-time simulator can be connected directly to power system control and protection equipment to test the equipment under realistic conditions • For detecting abnormal operating conditions that cannot be found through numerical models • For super-fast contingency analysis • Hydro-Québec develops HYPERSIM: a real-time simulator • Develop, improve and assess new protection and control concepts • Optimize the operation and the maintenance power systems • Decrease the time required to commission protection relays and control systems (FACTS, HVDC, SVC, etc..) • Reproduce events that occurred in the power system by using the actual protection and control systems

9. EMTP-RV • Simulation and analysis of electromagnetic transients • General purpose circuit analysis tool: wideband, from steady-state to time-domain • Detailed simulation and analysis of large scale electrical systems • Network analysis: network separation, power quality, geomagnetic storm, interaction between compensation and control components, wind generation • Synchronous machines: SSR, auto-excitation, control • Multiterminal HVDC systems, Power electronics • Series compensation: MOV energy absorption, short-circuit conditions, network interaction • Transmission line systems: insulation coordination, switching, design, wideband line and cable models • Switchgear: TRV, shunt compensation, current chopping, delayed-current zero conditions • Protection: power oscillations, saturation problems • Detailed transient stability analysis: more and more • Off-line tool: May save millions in design and operation!

10. Simulation and Analysis • The basis of all problems! • Modern power grids require advanced study and analysis methods • for power system design • operation • post-mortem analysis • Numerical models and solution methods now play a dominant role and contribute to all research and development levels. • The needs for grid simulations increase significantly faster than the capability of researchers to deliver models and faster simulations methods.

11. Simulation and Analysis • Simulation and modeling are essential for the evolution and operation of modern power systems • Can we build an electronic copy of the operated system? • Can we merge real-time and off-line simulation tools? • Can we replicate analog simulator style with numerical simulators? • What is the highest computational speed? • How far: wideband and size • Can we unify simulation environments to work with unique data sets and various analysis methods? • Can we create portable models and data? • Use Concurrent and multi-domain simulation methods

12. New trends: Cloud computing • Applications for power systems • Generation scheduling, unit commitment • Complex optimization problems • Load-flow • Probabilistic methods • Transient stability and electromagnetic transients • Acceleration of simulations • Sensitivity analysis • Contingency analysis • Dispatching of computing jobs into a resource pool • Simulation services with centralized and shared data • Increased utilization of available computing services • Higher automation levels • Reduced human intervention • Private cloud systems • Public cloud systems • Community cloud: organizations working together

13. New Trends: Parallel computing • Availability of increasing calculation capabilities through multicore computers • Power system simulations involve the solution of linear sparse systems • Traditional methods are generally sequential and use only one CPU • The matrices are very sparse, moderate size, coupled and unsymmetrical • For Load flow and steady-state studies the matrices are coupled but the solution is performed once • For time domain it is possible to use the natural delay of the lines to decouple the system. Not always feasible! • It is essential to explore new ways to increase the speed of calculations while maintaining accuracy • Hydro-Québec with Ecole Polytechnique of Montreal and RTE (France) are collaborating in an important research project to increase the speed of calculations using the possibilities offered by new technologies

14. New Trends: Collaborative computing, Co-simulation • Parallel computing can be done in a collaborative approach • Several simulation tools addressing different aspects, telecom, control, electromechanical and electromagnetic transients, collaborate together to simulate the same power system • Collaborative software environment can be implemented through a co-simulation channel in an indirect interaction (FMI) • Use Federated simulation systems run-time infrastructure (RTI) to support interoperability (HLA) • Scalable performance via parallel and distributed simulation techniques

15. Application: Large-scale Case diverse simulators (EMTP, Simulink)

16. Challenges • Decoupling : Where & How ??? • Delays (measurement/controlled source) • Transfer of slowly changing states: need for filters! • Automation of decoupling! • Diverse solution methods: • Synchronization issues (e.g. Check for instantaneous power injected by WTG !) • Global solution for all variables (not only interface) & impact on validity for all types of studies

17. Conclusions • Research on power system simulation and analysis tools is now facing new and major challenges: • Simulation of extremely large networks • Very complex networks, penetration of renewables energy • Smart Grids • New trends and means for solving increasingly complex problems • Parallel computations • Cloud computing • Collaborative computing • Advanced visualization methods • Data portability with CIM • Major research and revisions are needed in existing simulation tools