Secure and Scalable Microgrids Enabling Technology and Applications Rensselaer Polytechnic Institute Workshop on Microgrid Technologies and Applications October 10-11, 2013 Steve Glover Electrical Sciences and Experiments Department Manager Sandia National Laboratories Albuquerque, NM 87185 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Outline Overview of the Electrical Science Group Microgrids DOE related microgrid activities Secure Scalable Microgrid 2
System & Components Physical Environments All stockpile-to-targetsequence (STS) phases Nuclear Weapons Stockpile Responsibilities Drive Deep Expertise in Grid-relevant Science and Engineering Launch Boost Midcourse Over Target Terminal Weapon storage, transportation, maintenance, storage on delivery platform, launch and in-flight path Normal Environments (EMR, ESD, nearby lightning, degaussing) Abnormal Environments (lightning, exposure to power sources) Hostile Environments (nuclear weapon effects, directed energy weapons, high power microwaves) Grid-relevant Science and Engineering at Sandia Advanced power systems and AC/DC microgrids High voltage breakdown science & experiments Pulsed power components and systems development Electromagnetics theory/code development Electromagnetic experiments Systems engineering and integration Other Capabilities include E-beam supported wind tunnel and high heat flux research 3
Electrical and Radiation Sciences Customers, Organization, and Facilities National security activities for and in collaboration with: Department of Energy (National Nuclear Security Administration, Office of Science, Office of Electricity) Other federal agencies (DOD-Army/USAF/NRL, DOT-Federal Aviation Administration, DOL Mine Safety and Health Admin.) Non-federal entities Industry (Goodyear, FMC, Inc., Lockheed Martin Technology Research) Universities EMP coupling into facilities World class accelerator technology development & high heat flux research Lightning protection Power systems All Electric Warship Sago mine, 2006 4
Power (GW) Current Grid is Evolving to Accommodate Different Energy Sources, Increased Reliability and Resiliency Today's Grid Transmission Power Distribution Loads Substation Generation Forecasting is used to set generation 30 28 26 24 22 20 Available resource forecast Actual load Day ahead demand forecast California ISO 0 4 8 12 16 20 24 Time of day (hours) Renewable sources Centralized generation Excess generation & fuel storage Fixed infrastructure Demand forecasting Essentially open loop control with human in the loop Limited ability to support renewable sources Limited ability to support disruptions Smart grid initiatives 5
Advanced Energy Surety Microgrid (ESM) Projects DOE & DoD R&D To address current shortcomings of power reliability and security, Sandia is investigating advanced microgrid approaches to make distributed energy generation and storage resources more reliable, cost effective, and secure to improve overall critical mission assurance. Sandia s microgrid research utilizes smart grid technologies to enable: Distributed energy generation and storage to be operated both gridtied and islanded, Energy demand/response, Increased use of renewables Secure cyber control, Improved reliability and resiliency, and Use DoD sites as initial test beds. DOE & Utility R&D Provide higher energy reliability and resiliency to critical community and industrial infrastructure and operations for low probability but high consequence events (natural disasters, intentional events, or large accidents). Enhance energy safety, security, and reliability for civilian applications with a focus on: Providing energy resiliency using distributed generation to maintain critical community functions and operations for extended outages, Support demand/response of distributed community generation and storage to support local utility distribution system. 6
Community/Utility Coupled Microgrid Efforts Help to Accelerate Commercial Smart Grid Applications Studio Substation Studio 14 Feeder (12.47 kv) 115 kv System Utility Other Load And PV Residential (under construction) PNM Microgrid Project Large-scale PV (500 kw) Large-scale Storage 250 kw 4 hr. energy battery 500 kw, 40 min power battery Smart Grid / SCADA integration NEDO Microgrid Project Energy storage (small) Gas Engine (240 kw) Fuel Cell (80 kw) PV (50 kw) Demand response? 100 kw Dummy load Electric Chiller/Thermal storage 7
Networked, Secure, Scalable Microgrids (SSM TM ) Enable High-Penetration Renewables and Improved Operations Ground breaking nonlinear control theory, informatics, and innovation. Tools are being developed for networked microgrids spanning from conventional to 100% stochastic generation. Potential impact: Unlimited use of renewable sources Lower-cost provisioning at a given level of renewables Reduction in centralized fossil fuel based sources Self-healing, self-adapting architectures Microgrids as building blocks for larger systems Lanai Hawaii Bus cabinet Rotational machines SSM test bed 8
Tiered Control Structure Enables Prioritization and System Adaptability 9
The Basic SSM Test Bed Structure Enables a Flexible Research Platform Agent Agent Communication network Control Control Generation Sources or other Microgrids New power system components will increase complexity associated with control and performance. UPFC Agent RE Agent Dispatchable Generation Control Agent Power Distribution Connections Loads Control Agent Storage Systems RE Control Agent 10
SSM Test Bed Exhibits Dynamics Similar to the Grid Inter-area oscillations Datalink Engine (emulator) Speed Energy storage can improve resiliency Control attributes influence stability 11
Demonstrated Performance with 100% Stochastic Generation and Load is Enabled Through Controls and Storage Sources 2 - Stochastic Stochastic Source #1 Stochastic Source #2 Agents were not part of this experiment. 12
Hamiltonian Based Control Approach with Full State Control Reduces Bus Voltage Transients Source and load profiles Stochastic source #1 Transients are not evident in the bus voltage Stochastic source # 2 Load Cyan load current Red diesel current Light blue wind current Purple load current Green commanded profile Dark blue Bus energy storage current Blue actual profile Red indicates progress in time 13
Cost: J= ( i ARESE - E(i ARESE ) ) 2 dt (V 2 sec) i load (A) Understanding and Leveraging Information Flow in a Power System is Necessary for Optimal Performance v load (V) Cost: J= ( v load - E(v load ) ) 2 dt (V 2 sec) Batch-run experiments enable apples to apples control comparisons Example shows the effect of Informatic control update rate on cost 5 Load Current vs. Time - Comparison of Update Rates 200 Load Voltage vs. Time - Comparison of Update Rates 4 3 150 1 Hz (1 sec interval) 2 Hz (500 msec interval) 10 Hz (100 msec interval) 100 Hz (10 msec interval) 2 1 1 Hz (1 sec interval) 2 Hz (500 msec interval) 10 Hz (100 msec interval) 100 Hz (10 msec interval) 0 0 10 20 30 40 50 60 70 80 90 100 t (sec) t f J ( t ) i ( ) iˆ ( ) d i f t 0 ES ES 2 100 50 0 10 20 30 40 50 60 70 80 90 100 t (sec) v f t f t J ( t ) v ( ) vˆ ( ) d 0 load load 2 15 10 Performance vs Update Rate Control bandwidth of ServoControl Nyquist frequency of variable load f c of bus based on min/max resistor values Experiment Data 6000 5000 4000 Performance vs Update Rate Control bandwidth of ServoControl Nyquist frequency of variable load f c of bus based on min/max resistor values Experiment Data 3000 5 2000 1000 0 10 0 10 1 10 2 Agent Update Frequency (Hz) 0 10 0 10 1 10 2 Agent Update Frequency (Hz) 14
Networked Microgrids can add to Power System Reliability and Resiliency Microgrid #3 Microgrid #1 Microgrid #2 Master Controller 15
SSM Testbed Allows Study of Microgrid Collectives Centralized data acquisition allows plotting/analysis in Matlab 16
In Summary Sandia Electrical Sciences research is addressing a wide range of power system challenges Controls, stability, protection, and susceptibility Sandia s Energy Surety Microgrid research is addressing reliability and resiliency of DoD and commercial microgrids through near term technologies Sandia s Secure Scalable Microgrid research is integrating: Informatics theory (including cyber security), Hamiltonian based controls, Communication theory, and flexible experimental capabilities Scalable approaches to networked microgrids support the building block concept DC system control approaches are being migrated to AC systems 17