Solar Enablement Initiative

Solar Enablement Initiative Distribution State Estimation – for real!

Olav Krause

SEI Project Leader

ARENA Insights Forum 25th June 2019

Increasing Visibility of Distribution Networks to Maximise PV Penetration Levels – Project Partners

Solar Enablement Initiative

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• This project aims to support electricity distribution companies to take a less conservative approach in assessing and approving additional customer photovoltaic (PV) systems to be connected to their networks.

• This is achieved by providing them with a better understanding of the operational conditions of their networks through the application of a proven state estimation technique (SEA) that generates an estimate of the networks’ operational conditions.

• These estimated results will form part of a network analysis tool through which the likely impact of the additional PV systems can be assessed.

Project Objective

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Solar Enablement Initiative

Solar Enablement Initiative

• In a sense we’re going through what Transmission Systems went through in the 1970’s.

• Transmission Systems used to be monitored by manned substations equipped with telephones.

• Advances in ICT and digitisation of measurement equipment led to measurement data being telemetered to Transmission control centres.

• This has enabled automated secondary assessment and analysis processes driving up efficiency and reliability, such as:

• Topology optimisation• Reactive power optimisation• Contingency generation re-dispatch• (N-x) calculations• Short circuit studies• Network constrained dispatch and trading

The key: State Estimation

Why State Estimation?

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DSSE - a ‘Hardware Abstraction Layer’Energex:~40% DTX*

measurements

United Energy:>90% Smart Meter coverage

TasNetworks:Re-closer and Regulator measurements

Solar Enablement Initiative

Voltage profile

Current profile

~20 DTX ~100 DTX ~350 DTX*DTX: Distribution Transformer

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Solar Enablement Initiative

DSSE result precision (current MV trial)

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• A largely residential feeder

• 36 distribution transformers 315 kVA to 750 kVA

• 25% monitor coverage (9 of 36 have transformer monitors).

• Feeder for real time deployment.

• Hosts PV system for dynamic export limit trial.

Estimation vs. SCADA

Measurement vs. estimated uncertainty

DSSE - on MV and LV levelStand-alone systemWith current integration:- OSIsoft PI- ARCgis ESRI- Siemens PSS®Sincal

Solar Enablement Initiative

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own dashboard

Siemens PSS®Sincal with exported results

ESRI with result visualisation

PI Vision with result visualisation

Solar Enablement Initiative

DSSE – unprecedented knowledge of system performance

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Node graphs& Maps

Heat Maps

Time series Histograms

• DSSE provides a basis for better decision making, off-line and in real-time

• Off-line value stems from detailed network performance assessment• E.g. assessing asset utilisation

• Regulatory compliance and reporting

• Planning, including investment, operational and connection assessment (project objective)

• Real-time value stems from situational awareness for improved operational decision making (manual and automated)• E.g. dynamic export/import limits (project objective, two demonstration sites)

• Use of controllable network devices (e.g. OLTC, regulators, capacitor banks,…)

• Possibly provision of Operational Envelops and Dispatch Constraints

DSSE - where is the value?

Solar Enablement Initiative

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Solar Enablement Initiative

Distribution State Estimation – for real!