___________________________________________________________________________From: JL COULLON

Date March 11, 2011

Subject: Spec-in for Phasorpoint WAMS Offering – V1.1___________________________________________________________________________

Overview

This document includes the Description of a Wide Area Measurement System WAMS, recommended to address the new issues associated to the large interconnected electrical network such as unstability/oscillation risks associated to long interconnection lines, island resynchronization after grid separation, and so forth. This system is a major move into a smarter grid operation, fully in line with latest worldwide trends.

1 Wide Area Monitoring System

1.1 Introduction. Purpose of System

The contractor shall provide a Wide Area Monitoring System WAMS that shall be capable of integrating Phasor Measurement Units and associated applications relevant to the power system dynamics context.The purpose of the WAMS shall be to take advantage of the latest technologies to address the new issues related to the interconnected electrical network including: Assessment and detection of unstability/oscillation risks associated to long interconnection lines

between regions, Fast detection of islanding situations, and islands resynchronization after grid separation Analysis of any specific Power System dynamics issues not visible via traditional SCADA

measurement techniques

Voltage and angle measurements from PMUs shall also be made available to the SCADA subsystem via industry standard protocol IEC 60870-5.104 and used to improve the quality of the State Estimation solution.

The WAMS shall be based on a dual redundant hardware configuration and include: the acquisition subsystem the PMU data storage and monitoring subsystem applications for advanced analysis an interface to the Advanced Monitoring and Visualization tool exporting key WAMS data and

alerts for Situation Awareness

1.2 PMU Location Study

The Contractor shall include in its offer a study by consulting domain experts to produce an analysis of the situation of the interconnected Power System dynamics. These experts shall produce a report describing: The nature and extend of the issues to be monitored for reliable interconnected Power System

operation in the domain of Power System dynamics and WAMS, as outlined in the Introduction section above

The number and location of PMUs recommended for proper monitoring and management of the issues identified above

The recommended location of the priority PMUs to be installed with the following constraints:o A maximum of 50 (fifty) PMUso PMU connectable on the existing telecommunication network

Any proposals for extensions or improvements relevant to the Power System dynamics domain.

1.3 PMU devices and communication facilities

The Contractor shall make the provision and installation of the priority PMU devices at the location identified in the PMU Location Study. When extensions of Telecommunications backbone facilities are required to connect the PMUs, these shall be Purchaser’s responsibility.

1.4 Hardware configuration

The system shall run on a separate pair of servers. These servers shall comply with the requirements expressed in the IT Infrastructure section for the servers of the Control Center Hardware configuration.

The WAMS client shall be available on dedicated User Interface consoles. It shall be possible also to run WAMS User Interface on the EMS consoles.

The access to the WAMS User Interface shall be properly protected: Individual user logons (logged for security) with password protection Password protected privilege groups (e.g. for providing password protection for alarm threshold

settings)

1.5 Acquisition subsystem

A central Phasor Data Concentrator PDC shall be provided to interface with PMUs in the substations. The PMU interface shall be compliant with IEEE C37.118-2005 standard.

The PDC shall have extension capabilities to accommodate extension of the PMU quantities. It shall be possible in the future to extend this central PDC with: A Central PDC interfacing to the WAMS server(s) Regional PDCs concentrating PMU data for the Central PDC Substation PDCs routing PMU data in the substation to the Regional PDCsWhen using this extended architecture, the system shall be expandable to support at least 5000 input phasors in the future.

The Acquisition Subsystem shall provide the following capabilities:

accommodate incoming PMU data at all data rates defined in IEEE C37.118-2005 standard, including sample rates of 50 or 60 samples/second

support simultaneously multi-vendor PMU’s, with proven capability to work with at least 5 different PMU vendor’s devices

proven capability to accept multi-bus, multi-circuit PMU’s (e.g. 6 voltage phasors and 18 current phasors)

update with new PMU data at least every second, or more frequently where appropriate assign individual phasor measurements either as sets of 3-phase inputs (in an order defined by

the user), or as positive sequence values. For example, a PMU measuring three current inputs shall be used either to measure all three phases in a single circuit, or to measure three separate circuits (assuming balanced phase)

ability for incoming phasors to be inverted or re-scaled individually, to aid recovery from misconnection of CTs or VTs

read symmetrical components from IEEE C37.118-2005 data streams and also calculate symmetrical components from three phase data

producing output data streams in IEEE C37.118-2005 format for hierarchical PDC operation. The administrator shall have full flexibility to specify any measured value to be included in (or excluded from) the output stream, and to define the output data rate. If the data is down-sampled, it shall be pre-filtered to avoid aliasing

tools to help setup configuration for roll-out of large numbers of PMU’s, including storage of configuration settings, PMU and alarm configuration cloning

1.6 PMU monitoring and data storage

The Data Storage function shall provide the following capabilities: the data storage capability shall not be limited by the design but subject to size of hard disk(s)

only. data storage shall be driven by automatic and manually triggered event. SQL access to database shall be provided to allow external applications to directly access

WAMS data using an ODBC compliant interface.

The Monitoring function shall provide the following capabilities: Topological overview display of phasor data and oscillation application data, with user defined

background image Substation view of phasor data and oscillation application data Drill down from overview display to substation detail Flexible phasor groupings to support uncluttered overview displays Capability to calculate Active and Reactive Power (from V and I) and Power factor (cos Φ) Capability to calculate user defined quantities based on addition, subtraction, multiplication and

division of scalar and complex values and constants Ability to define Alarms on monitored data Ability to save and restore alarm configuration settings Ability to view, sort and filter event logs for alarm and systems events

The system shall be self-monitoring, and provide the capability to raise alarms and gather statistics on the following: loss of GPS clock accuracy packet Loss

disconnection of PMU

WAMS Alarms shall be interfaced to the EMS.

1.7 User Interface

A map view of the Purchaser network area shall be provided, for both localized regions and the entire system. Intuitive navigation and drill down capability into the measurement level and the application results shall be provided.

A graphical representation of voltages angle and magnitude shall be provided for real time monitoring, together with any defined angle differences.

Screens update shall occur at least 10 times per second in order to visualise with smooth motion the rapid changes that can be observed thanks to the PMUs, during events like system separations.

Live strip charts shall be provided.

1.8 Advanced Applications

1.8.1 Advanced calculations and Alarming

PMU measurements shall be usable in complex calculations such as the calculation of line parameters from PMU measurements at both ends of a transmission line, resulting for example in the dynamic rating of line thermal capacity.

Advanced alarms shall be used to identify high-level warnings of wider system threats, taking advantage of the synchronisation of PMU data. This facility shall be applicable to wide-area system events such as the incipient conditions of a potential voltage collapse.

It shall be possible to configure User definable composite alarm events to operate on any logical combination of limit violations based on PMU data and calculated results. As an example, it shall be possible to build calculation of flexible wide-area alarms arising from several simultaneous geographically separate observations, including: low- or high-level measurements high positive or negative rate of change over a user-defined period application results such as oscillation damping and amplitude

Hysteresis shall be applied to alarms to avoid spurious events or premature clearing of the event.

1.8.2 Management of Power System Separation

This application shall be designed to alarm on system separations and provide real time tools to support management of islanding, re-synchronisation and blackstarts. It shall include the following features: event & alarm triggering on detection of system separation intuitive, geographical display of islanding conditions, based on frequency and relative rotation

of voltage vectors representation of relative voltage angle to show partial reconnections short term historic display of minimum and maximum frequencies

1.8.3 Oscillatory Stability Management

The Contractor shall deliver a field proven Oscillatory Stability Management (OSM) application for the management of governor (0.01-0.1Hz ) and electro-mechanical (0.1- 4Hz) modes of oscillation. A list of references operational in the field shall be attached to the offer. The OSM application shall be capable of: Oscillatory analysis on active power, system frequency and phase angle difference Fast analysis of power system dynamics for operational alerts and alarms Analysis of power system dynamics for system testing and long-term review Simultaneous detection of multiple modes of oscillation (with a minimum of 7 user specified

mode bands) Real-time mode shape analysis and display Mode frequency histograms over user defined time periods Real-time locus plots for each mode band (mode amplitude vs mode decay time) Flexible alarming on mode frequency, amplitude and decay time, including

o User defined exclusion areaso User defined on and off hysteresis settings

Identify if an area is contributing to an oscillatory mode, when PMUs are installed on all circuits bounding the area

Show the relative contribution to a specific oscillatory mode of any generator equipped with PMU(s)

Show the power flows connected with each separate mode of oscillation

1.9 Interface to SCADA and EMS

Key WAMS application results and alerts shall be available in the Advanced Monitoring and Visualization tool of the EMS for Situation Awareness.

The WAMS data to be made available include: Voltage angle and amplitude to be used by the State Estimator, at a rate compatible with the

SCADA requirements; the IEC 60870-5.104 protocol shall be used to send PMU data to the SCADA for this purpose

Alerts detected by PMUs Application results such as oscillation mode frequency, amplitude and decay time.