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SFT Implementation Project

Project Update

31 March 2011: SFT Implementation Go-live Status Summary now available see the Related Information section.

28 March 2011:  As at 10.00am this morning, after 6 weeks of pre-scheduling and scheduling, SFT seamlessly took real time control of constraint generation for the power system. A further project update will be published later in the week.  The Security Constraint information on the Security Management page has now been updated.

31 Jan 2011:We are now in the final stages of implementing the SFT software.  We are inviting participants to register their interest in attending a presentation in late March or early April to, among other things:

• explain the use of SFT
• describe how SFT is used to create constraints
• explain the circumstances and process for using manual constraints
• explain any changes to the System Operator's constraint processes with the introduction of SFT
• answer questions you have on the SFT constraint process 

If you wish to attend the presentation please notify your interest to the System Operator email by 14 February 2011 to enable us to determine approriate date and venue.

Background

Security Constraints are applied to the SPD market clearing engine to ensure the power system is securely dispatched.

The System Operator is automating the way thermal security constraints are calculated using an application called Simultaneous Feasibility Testing (SFT), which was delivered as part of the System Operator’s Market Systems replacement programme (MSP). When implemented, SFT will allow the System Operator to determine and implement thermal security constraints dynamically.

Constraints built through this process will:

• use up-to-date and accurate network and injection data for developing constraints, therefore providing optimal application of security constraints
• automatically consider all realistic contingencies
• remove the current considerable manual process with attendant risks of error and conservative assumptions
• allow for efficient and more cost effective use of grid capabilities by market participants.

The use of SFT will therefore allow the System Operator to provide better management of constraints in real-time operation in a secure and efficient manner.

The proposed project timeline is as follows:

These timeframes are approximate and will be subject to change depending on any issues that arise during the operational testing.

Feedback on the content of this page can be sent by email to system.operator@transpower.co.nz for attention Fiona Abbott.

Methodology

The System Operator is required, at least two months prior to the introduction of SFT, to advise:

• an explanation of the methodology and procedures it will employ in formulating constraints, including how information about stability and transmission limits are used to define constraint parameters
• when the information can be published
• automated processes and systems used in formulating constraints.

The System Operator is also required to advise participants of the constraint percentage threshold, being the threshold at which SFT constraints are created. The initial threshold for SFT constraints is 90% and 0% for manual constraints.

The above is best illustrated in the linked process flowcharts below and the FAQs sheet in the Related Information below.

Industry Involvement

As part of the overall test phase for SFT implementation, the System Operator is building a test environment to enable selected participants to conduct their own due diligence on the effects of enabling SFT automated constraint generation on the operation of the market. This  will allow participants to:

• view the SFT outcomes from schedules and compare them with the existing production system outcomes
• select scenarios for the System Operator to run to test the SFT outcomes against previous outcomes
• test compatibility and integrate the SFT outcomes with their own tools

The participants involved in the testing are those who are most directly affected by such outcomes. Others are welcome to join in the testing, or to use the published testing results.

SFT data feed via WITS UAT – January-March 2011

We will with the assistance of NZX, continue to publish test SFT data in parallel with the current production Market System until SFT goes live.  This will enable market participants to compare the SFT data with current production system outputs.  The data feed can also be used as a test input for any systems that are being developed to utilise SFT data.

The "SFT on" parallel data feed will be re-enabled in the New Year, until SFT goes live in late March.  The feed will be kept as near to production as possible, but may vary slightly where changes have been manually applied to the production system.

Note that:

• The data feed will be maintained on a "best endeavours" basis
• It may be interrupted at times if the NZX test system is required for other purposes.  Any outages will be signalled to the participants in the usual way via WITS notices.
• During the period from mid February to mid March, the SFT environment will also be used for training OPS planners.  As they will be conducting scenario simulations, the data feed should not be considered parallel during this time.

The specific dates are shown in the timeline below:

Related Infomation