Collector substations, protection settings and energisation to the transmission network
Commissioning software for solar substations where switchgear, transformers and protection relays all have to be individually tested before the utility allows the plant onto its network.
A solar plant's collector substation steps generation up from the plant's medium-voltage collection system to transmission voltage, and it is commissioned to the same rigour as any grid-connected substation: switchgear, power transformers, protection relays and SCADA all individually tested and coordinated before the utility will allow the plant to close in. Deskely holds every bay, transformer and relay in one register with the protection testing and energisation gates built in.
- Assets
- Switchgear bays, transformers, protection relays
- Test
- Protection coordination, transformer test, SCADA integration
- Interface
- Transmission network and utility control centre
- Gate
- Grid connection agreement sign-off
Choose your project type
The problem
The substation is the one asset the whole plant depends on, and its commissioning record cannot be a folder of vendor test certificates handed over the week before energisation.
A collector substation is built by a specialist electrical contractor on a different schedule to the PV field, with switchgear, power transformers and protection relays each supplied, factory-tested and site-tested by different vendors against a protection coordination study the utility has to approve.
When protection relay settings, transformer commissioning reports and SCADA integration tests sit in separate contractor binders, nobody can confirm before the utility's witness test that every relay is actually set to the approved coordination study, not the vendor's factory default.
Deskely tags every switchgear bay, transformer and relay individually against the approved protection study, so grid connection readiness is reported from verified settings rather than assumed from a contractor's sign-off letter.
Setting up the register
Bays, transformers and relays are tagged assets matched to the protection coordination study.
Single line diagrams, protection coordination studies and relay setting sheets are parsed into a reviewed register, so every switchgear bay, transformer and relay carries its approved setting and its manufacturer test certificate from day one.
Factory acceptance test records for transformers and switchgear are attached to the same tag that will carry the site acceptance test, so a discrepancy between factory and site performance is visible against one asset history rather than two disconnected files.
SCADA points, remote terminal unit (RTU) mapping and utility telemetry requirements are held as their own record set, distinct from protection testing, because they typically gate the utility's separate telemetry acceptance sign-off.
Execution
Protection testing, transformer commissioning and SCADA integration are proven bay by bay, then coordinated as a system.
Protection relays are secondary-injection tested against the approved coordination study, with pickup, timing and trip sequences verified per relay before a bay is cleared for energisation, and any deviation from the study logged as a finding against that relay.
Power transformers undergo site acceptance testing — insulation resistance, winding ratio, sweep frequency response and oil testing — captured against the specific unit, distinct from the switchgear bay it feeds.
SCADA integration testing confirms every tagged point reports correctly to the plant control system and, where required, to the utility's control centre, before the substation is presented for the utility's witness test.
Grid connection sign-off and handover
Grid connection is agreed from a verified protection scheme, not a promise that the relays match the study on paper.
The utility's witness test and grid connection agreement sign-off draw on the same relay and transformer test records built during commissioning, so the interconnection evidence package is an export rather than a last-minute assembly.
The handover pack for the plant operator includes as-built protection settings, transformer test data and SCADA point lists keyed to the substation register, giving the operations team the same record the utility relied on to approve connection.
Every signature carries a name, role and timestamp, which is what the utility's protection engineer and the asset owner's insurer expect before the substation is declared fit to remain energised unattended.
The dossier
Switching, protection and grid code evidence is held in the sequence it was actually executed.
Energising a collector substation is a sequenced series of HV switching operations under a permit-to-work regime, where a step out of order is the incident. The dossier holds each switching step, protection test and grid code witness record in the order it was signed.
Protection relay test record
each relay trips within the coordination study's time and current settings
prior to energisation of the associated bay
HV switching sequence and permit-to-work record
isolating, earthing and closing operations were executed in the approved order by the named authorised person
at each stage of substation energisation
Arc flash label verification record
the installed label matches the current arc flash study revision for that switchgear
before any live switching operation on the bay
Transformer and switchgear commissioning report
transformers and switchgear meet factory acceptance and site acceptance criteria before first energisation
at substation pre-energisation testing
Grid code compliance witness record
voltage and frequency response at the point of interconnection meet the network operator's requirements
during coordinated full-output grid code testing
Utility interconnection sign-off record
the network operator has accepted the substation for parallel operation
at commercial operation date readiness review
How it runs
From protection study to utility witness test.
Substation programmes reward a register that ties every relay and transformer back to the approved protection coordination study, because a single unverified setting is what a utility's witness test is designed to catch.
- 01
Model the substation by bay
Switchgear bays, transformers and protection relays modelled as assets tied to the approved coordination study.
- 02
Parse studies and setting sheets
Single line diagrams, protection studies and relay setting sheets drafted into a reviewed register with approved values attached.
- 03
Template protection and SCADA tests
Secondary injection, transformer acceptance and SCADA integration tests defined once, instantiated across every bay and unit.
- 04
Gate connection on verified settings
Grid connection sign-off reported from verified relay settings and transformer test data, with punch tracked to closure.
FAQ
Questions about Substation and grid connection scopes.
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