WASA and the Roadmap to WAMPAC at SDG&E

by Eric A. Udren, Dr. Damir Novosel, Dan Brancaccio, Quanta Technology, USA, and Tariq Rahman, SDG&E, USA

SDG&E Program

New and challenging grid operational reliability and safety concerns drive the advancement of synchrophasor methods at SDG&E, which has been gradually and continually building high-density PMU and data-gathering infrastructure for a decade. Real-time observation of the system operating state on basic client platforms aimed at P&C engineers has uncovered situations that were not visible to operators working on the legacy SCADA/EMS platform with its RTU and data-concentrator sources of low-speed unsynchronized data.  Engineers have also used the PMU data for post-mortem analysis of system events.  This visibility by engineering has shown the benefits of PMU data collection, raising the interest of system operators and leading to the deployment of a major control center WASA installation.  Figure 7 shows an example of a STATCOM oscillation problem that was not visible to system operators using SCADA data yet was causing customer service problems.

As WASA is established, engineers continue development of infrastructure and applications building toward the future of unified WAMPAC applications including those listed above.  Figure 8 shows SDG&E’s WASA and WAMPAC development roadmap.  As we explained above, fire risk reduction and improved system protection are among areas of development and deployment at this time.

Future Directions - Industry WAMPAC Roadmap Example
SDG&E has been following an industry roadmap for synchronized measurement system deployment which begins with basic infrastructure and familiarization and builds into WASA as it advances towards WAMPAC on a unified platform serving multiple users and mission-critical protection and control applications.  The roadmap steps are:
1.  Deploy a limited array of PMUs communicating data to engineers, to get practical first- deployment experience.  Observe transmission and/or distribution grid operation and share new findings.  Continue to add measurement sites as new relays are deployed.
2. Develop an organizational roadmap of use cases or applications, and required infrastructure to support them, with a sustainable investment plan.  Coordinate with and contribute specifications to the organization’s communications and IT investment and evolution plans.
3. Specify and deploy WASA in collaboration with System Operations, with a view towards evolution to WAMPAC.  Operators will develop skills and achieve the benefits of situational awareness, SCADA/EMS validation or enhancement.  Operators, engineers, and planners get the troubleshooting, DME, post-mortem analysis, and model validation benefits of WASA.
4. Deploy development and training platforms and environments, to be augmented going forward as new WASA and WAMPAC functions are integrated.
5. Tune system dynamic and short-circuit models as operating experience accumulates.  Develop and validate secondary-system modeling (P&C systems, instrument transformer and control connections, communications performance) for a variety of reliability-enhancement and reliability standards compliance purposes.
6. Develop and deploy supplemental non-redundant high-speed WAMPAC protection functions for trial use, WAMPAC system validation, and troubleshooting of reliability or data quality problems.
7. Build out fully-redundant PMU data collection and communications.  Manage performance to high levels of reliability.  Include timing distribution in the design.
8. Add P&C functions for faults, failures, instability, and RAS/SIPS scenarios.  These can be connected to trip after an initial operational validation.
9. Develop wide-area and high-speed control algorithms and test in simulations using tuned models, as well as on streamed real-time data.  Close the control loops to enter the full WAMPAC era.
10. The reliable and redundant PMU synchrophasor gathering system with return control paths is the new data platform onto which SCADA and EMS can now migrate to achieve a unified system for monitoring, control, automation, and protection.
11.  When deploying PMU applications, evaluate the use of synchronized measurements for distribution applications such as voltage monitoring and control, DER monitoring, or intelligent load shedding.

Let?s start with organization in protection testing