1 / 17

GridLAB-D – Dynamic Simulation Capabilities

PNNL-SA-131557. GridLAB-D – Dynamic Simulation Capabilities. Frank Tuffner. Pacific Northwest National Laboratory. WECC Model Validation Working Group Salt Lake City, Utah – January 24, 2018. GridLAB-D: A Unique Tool to Design the Smart Grid.

pollyr
Download Presentation

GridLAB-D – Dynamic Simulation Capabilities

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PNNL-SA-131557 GridLAB-D – Dynamic Simulation Capabilities Frank Tuffner Pacific Northwest National Laboratory WECC Model Validation Working Group Salt Lake City, Utah – January 24, 2018

  2. GridLAB-D: A Unique Tool to Design the Smart Grid Unifies models of the key elements of a smart grid: Over 55,000 downloads in over 150 countries Power Systems Loads Markets • Smart grid analyses • field projects • technologies • control strategies • cost/benefits • Time scale: sec. to years • Open source • Contributions from • government • industry • academia • Vendors can add or extract own modules • Open-source, time-series simulation of an operating smart grid, from the substation to individual end-use loads & distributed energy resources, in unprecedented detail • Simultaneously solves 1) power flow, 2) end-use load behavior in tens of thousands of buildings and devices, 3) retail markets, 4) control systems, and 5) electromechanical dynamics.

  3. GridLAB-D Capabilities • Performs time-series simulations • Seasonal effects (days to years) • Midterm dynamic behavior (secs to hrs) • System dynamics (milliseconds) • Simulates control system interactions • Device- and system-level controls • Market interactions Typical Use Cases Interconnection of distributed generation and storage New and innovative retail market structures (e.g., DSOs) Evaluation of demand response and energy efficiency Volt-VAr optimization and conservation voltage reduction design Sectionalizing, reconfiguration, automation, and restoration Microgrids and resiliency

  4. Definitions for this presentation • Dynamic simulation can include time series (timestep greater than 1 second) • For this presentation, quasi-steady state simulation is defined as having a timestep at 1 second or greater • Sequence of powerflow states coupling other behaviors, such as multi-state load models • Focused typically on 1-minute or longer range – behavioral and diurnal dynamics • For this presentation, dynamic simulation is defined as having a timestep less than 1 second • Sequence of powerflow states coupling differential equations • Focused mainly on 0.5 ms to 50 ms range – electromechanical dynamics

  5. General “deltamode” capability • Deltamode is the GridLAB-D capability to enable timesteps less than 1 second • GridLAB-D has the ability to transition in and out of this simulation mode • Start simulation in quasi-steady state • Transition into deltamode • Transition back into quasi-steady state • Repeat as necessary

  6. Dynamic Simulation Usages • Transients on distribution systems • Tripping of IEEE 1547A devices • Grid Friendly Appliance™ impacts • Microgrid Analysis – Resiliency • Inrush and line charging • Overhead and underground lines being energized • Transformer saturation • Motor starting surges • Frequency and voltage impacts • Acceptable ranges • Secondary tripping of items • Evaluate methods for improving resiliency

  7. Overall Module Support • GridLAB-D modules that have deltamode support in some form • Powerflow (all objects support it, on some level) • Reliability (ability to induce events at subsecond scales) • Generators (diesel generators, inverters, and simple battery/solar) • Residential (house has initial participation, but most models do not support)

  8. Object models Implemented • Synchronous generation • Inverter-based generation • Line/Load charging • Transformer saturation • Single-phase induction motors • Three-phase induction motors • Variable frequency drives

  9. Synchronous Generators • Three-phase, unbalanced interfacing • Synchronous machine model • Variety of governors implemented • (None) • DEGOV1 • GAST • GGOV1 (two forms) • Constant real power dispatch(PI-controlled) • Several exciter modes • (None) • SEXS • Constant reactive power dispatch(PI-controlled) Terminal voltages for three diesel generators on123-node test system for a load step change

  10. Inverters • Three-phase or single-phase interfacing • Use with photovoltaics or energy storage (batteries) • Optional ramp-rate implementations • Optional IEEE 1547/1547A checks, or custom limits • Two primary modes of operation: • Grid following • Constant PQ dispatch • Constant PF mode (PV) • Volt-Var Adjustment/Response (Rule 21) • Load following • Voltage source • Droop-based response (P and Q) • Isochronous operation Base VSI Controls Droop mode controls for VSI

  11. Line/Load Charging • Model in rush associated with induction/capacitance charging • Inductance field establishment • Line capacitance charging • Impedance-based loads • Ability to translate I-P loads to Z to model Simple overhead line energization – GridLAB-D and PSCAD results

  12. Transformer Saturation • Builds off the line/load charging • Models the saturation of the transformer windings • Grounded Wye-Wye supported right now Transformer current in 8500-node system during connection of primary transformer Transformer Saturation Curve Transformer current in 4-node system during transformer connection

  13. Single-phase Induction Motors • Attach to primary or secondary voltage systems • Multi-state to capture starting, stalling, and tripping behavior • Most dynamics portions on the dynamic-phasor implementation of:B. Lesieutre, D. Kosterev, and J. Undrill, “Phasor modeling approach for single phase A/C motors,” Proc. of 2008 IEEE PES General Meeting, pp. 1-7, 2008. Power measurements at a running motor and starting motor on simple 4-node system Motor state during fault on distribution feeder

  14. Three-phase Induction Motors • Multi-state to capture starting, stalling, and tripping behavior • Dynamics based on:B. Braconnier, “Dynamic Phasor Modeling of Doubly-Fed Induction Machines Including Saturation Effects of Main Flux Linkage,” M.S. Thesis, Univ. of British Columbia, Sept. 2012 • Currently being validated/tested Three-phase induction motor voltage change simulation in GridLAB-D and PSCAD

  15. Variable Frequency Drives • Attaches to three-phase systems, at the moment • Simplified AC-DC-AC conversion model • Simplified average-model implementation • Frequency ramping start (constant torque mode) • Constant speed (variable torque mode) • Still being fully validated Example efficiency table for VFD

  16. Dynamic Simulation – Path Forward • Current research/work • Complete validation of three-phase induction motor model with PSCAD • Investigate single-phase induction motor further • Incorporate further/more detailed protection modeling into motor models • Expand transformer saturation to other types • Validating the transitions in greater detail/testing • Potential future work • More co-simulation ties • Further microgrid-related controls

  17. Further Information Deltamode-related questions Contact Frank Tuffner francis.tuffner@pnnl.gov 206-528-3124 GitHub Links https://github.com/gridlab-d/gridlab-d Wiki http://gridlab-d.shoutwiki.com/wiki/Main_Page SourceForge Forums https://sourceforge.net/p/gridlab-d/discussion

More Related