GWSC-PV Solar PV SCADA Monitoring and Control System

Core Capabilities

• Full‑voltage‑grade coverage: Monitoring for 0.4kV commercial‑industrial rooftop PV, 11kV collection & boosting, 33kV medium‑high‑voltage collection & boosting, and 132kV large‑scale PV booster stations. Protection settings shall be tuned according to actual grid‑connection voltage levels.
• SCADA telecontrol & telemetering functions (Telemetry, Teleindication, Telecommand, Teleadjusting): Automatic execution of active/reactive power adjustment commands issued by utility dispatch.
• PV‑specific grid‑connection logic: Anti‑islanding Protection Relay and Fault Separation Relay implement anti‑islanding, over‑voltage / under‑voltage, over‑frequency / under‑frequency, fault separation and reverse‑power protection. Operating time for anti‑islanding and fault separation ≤ 40ms. Line, transformer, capacitor and PT‑voltage‑monitoring protection relays are deployed locally at respective primary bays and make decisions independently without relying on station‑control‑level host.
• Optional wide‑band oscillation monitoring: Detects sub‑synchronous / super‑synchronous oscillation risks induced by high‑penetration power‑electronic equipment. Captures harmonic and inter‑harmonic anomalies to facilitate fast oscillation‑source location.
• On‑site power‑quality monitoring: Real‑time measurement of harmonics, three‑phase unbalance, power factor and other power‑quality indicators; historical‑data storage and traceability for power‑quality assessment and subsequent improvement.
• Fault recording, Sequence‑of‑Events (SOE) logging (resolution ≤ 1ms), multi‑level audio‑visual alarm, generation‑data statistics & reporting.
• Communication‑status self‑diagnosis: Continuously monitors network connectivity and data quality of protection relays & measuring‑control units. Raises alarms and blocks remote‑control commands upon anomalies to avoid mis‑operation or refusal‑to‑operate caused by communication failures.
• Complies with power‑system security‑zone specifications (security zone I / II / III isolation). Supports security encryption gateway for dispatch data‑network transmission, satisfying technical requirements for new‑energy grid‑integration.
• Optional Grid‑Restore Synchronization Auxiliary Module for large‑scale plants: Issues ordered inverter re‑synchronization commands after utility grid restoration per dispatch commands or preset strategies to suppress inrush‑current impact from simultaneous re‑closing.

System Composition

• The complete system consists of thirteen modular‑designed complete panels plus distributed secondary‑level devices. All panels are modular and selectable‑on‑demand for flexible configuration across different‑voltage‑grade PV plants.
  Standard panel dimension: W × D × H = 600 × 800 × 2260 mm

GWPC‑TP Main‑Transformer Protection Panel (for 33kV / 132kV plants)

• Dual‑redundant main‑transformer protection units are deployed, incorporating differential main‑protection, backup‑protection (complex‑voltage‑restrained over‑current, zero‑sequence over‑current, over‑load), non‑electric protection (Buchholz relay, winding temperature, pressure release) and bay‑mounted measuring‑control unit. Dual‑redundant protection adopts independent CT/PT windings and tripping‑output loops to fulfill relay‑protection dual‑redundancy requirements, ensuring fast and reliable fault clearing for main‑transformer safety.

GWPC‑PVG PV Grid‑Connection Protection Panel

• This dedicated panel for PV grid‑connection integrates three core devices: Anti‑islanding Protection Relay, Fault Separation Relay and power‑quality‑monitoring unit. It monitors grid‑connection‑point voltage, current, frequency, harmonics and three‑phase unbalance. It delivers anti‑islanding protection, fast fault separation (≤ 40ms) and full‑station power‑quality data logging to guarantee safe and compliant PV grid connection.

GWPC‑RTU Remote‑Communication Panel

• Equipped with remote‑terminal‑unit (RTU), communication‑management unit, GPS / Beidou dual‑mode time‑synchronization device (time‑synchronization accuracy ≤ 1ms), ring‑network switch and station‑control‑layer switch. It aggregates data from all secondary‑level devices, performs protocol‑conversion and organizes data for uplink transmission via IEC 60870‑5‑104 to dispatch master station for bidirectional interaction. Unified GPS/Beidou time‑synchronization ensures consistent time‑stamp across all plant events. Dual‑redundant configuration (dual RTUs and dual switches) ensures reliable intra‑station communication with zero‑switch‑over‑delay upon key‑link failures.

GWPC‑AGVC AGC/AVC Control Panel

• Serves as the core of plant‑level intelligent power regulation. It receives power‑set‑point commands from utility dispatch, and automatically adjusts full‑station active and reactive power according to real‑time generation output, grid‑point voltage and ambient irradiance. It stabilizes grid‑connection voltage and power‑factor to satisfy dynamic‑voltage‑and‑frequency‑control requirements. Supports dispatch‑curve tracking, local‑parameter setting and emergency manual intervention.

GWPC‑SPF Solar Power Forecasting Panel

• Interfaces with on‑site meteorological sensors (irradiance sensor, anemometer, temperature‑humidity sensor). Collects real‑time irradiance, ambient temperature and wind‑speed data. Intelligent algorithms generate short‑term (0‑72h) and ultra‑short‑term (0‑4h) PV‑generation forecasting profiles, which are periodically uploaded to dispatch master station to support utility‑grid load dispatching and new‑energy consumption.

GWPC‑PFR Primary Frequency‑Regulation Panel

• Designed for medium‑and‑large‑scale PV plants. It monitors grid‑frequency fluctuation and responds without external commands by rapidly adjusting PV active‑power output to mitigate grid‑frequency deviation. It meets GB/T 40595 and State‑Grid technical specifications & assessment criteria for primary‑frequency‑regulation of grid‑connected power sources.

GWPC‑LP Line Protection Panel (for 132kV outgoing transmission lines and critical 33kV tie‑lines)

• Equipped with high‑voltage line longitudinal‑differential or distance‑protection relay. Functions include optical‑fiber differential protection, three‑zone phase‑to‑phase / earth distance protection, four‑zone zero‑sequence over‑current protection and auto‑reclosing. Supports dedicated optical‑fiber channels or multiplex‑channel communication. Delivers fast main‑protection operation (≤ 25ms) and high auto‑reclosing success‑rate for high‑voltage transmission‑line scenarios.

GWPC‑CCM Common Measurement & Control Panel (for 11kV / 33kV / 132kV plants)

• Configured with common‑purpose measuring‑control unit. Collects common analog quantities (bus‑bar voltage, frequency, station‑service‑power current) and binary‑status signals (GPS/Beidou status, ambient temperature‑humidity, fire‑alarm, security‑alarm) not covered by dedicated‑bay protection units. Aggregates operational data (temperature, power etc.) from pad‑mounted transformers and uploads to SCADA host via communication‑management unit. Provides complete plant‑level‑operation pictures and supports remote‑control of common‑purpose equipment such as station‑service‑power supply.

Optional note: For 0.4kV distributed projects, this panel may be simplified or cancelled; related functions can be partially fulfilled by inverter data‑acquisition unit or SCADA host.

GWPC‑DFR Fault‑Recording Panel

• Dedicated fault‑recorder captures voltage‑current waveforms and binary‑status changes from 10s pre‑fault to 60s post‑fault. It connects analog‑quantity and binary‑quantity signals from key bays including 132kV/35kV/33kV collection‑bus branches, each side of main‑transformers, SVG and earthing‑transformer. Data is stored in standard COMTRADE format for waveform playback and analysis, supporting incident‑root‑cause tracing, protection‑setting verification and fast fault restoration. Fault‑recording files can be uploaded to SCADA host via station‑control‑layer network and transmitted to dispatch side. GPS/Beidou time‑synchronization interface ensures time‑stamp consistency with plant‑wide SOE records.
• Optional note: May be simplified or cancelled for 0.4kV low‑voltage distributed PV; simplified recording functions of inverter or power‑quality‑monitoring unit can serve as alternative. Recommended as standard‑configuration for 11kV / 33kV / 132kV and higher‑voltage‑level projects.

GWPC‑DDN Dispatch Data‑Network Panel [Optional]

• Equipped with dispatch‑dedicated network devices, security encryption gateway and security‑isolation devices. Strictly deployed following power‑security‑zone‑partition rules (physical isolation between security‑zone I / II / III). Realizes encrypted transmission of dispatch telecontrol‑telemetry data, power‑forecasting profiles, regulation commands and fault‑alarm data.
• Optional note: Standard‑configuration for 132kV booster stations. Subject to local‑utility‑dispatch‑access requirements for 33kV plants. Generally not applied for 11kV and 0.4kV distributed projects; alternatives: RTU plus security‑access‑gateway to satisfy grid‑access compliance.

GWPS AC‑DC Power‑Supply Panel

• Provides uninterrupted AC‑DC operating‑power for all panel‑mounted and distributed protection relays. Built‑in over‑voltage, over‑load and short‑circuit protection. Battery‑bank backup duration ≥ 2h (expandable). Guarantees continuous operation of secondary‑level devices during mains‑supply anomalies and utility‑grid faults.

GWPC‑MTR Tariff Metering Panel

• High‑accuracy 0.2S‑class gateway‑meter and energy‑acquisition‑terminal are deployed. Precisely measures total generation, grid‑feed‑in energy, self‑consumed energy and time‑of‑use energy. Supports data storage, traceability and remote‑transmission, fulfilling settlement and utility‑verification requirements.

GWPC‑SCADA SCADA Host Panel

• Accommodates monitoring‑workstation, display terminals, audio‑visual‑alarm hardware and GWSC‑PV proprietary SCADA software. Functions include single‑line‑diagram visualization, real‑time‑data monitoring, trend‑curve display, fault‑alarm, fault‑recording analysis, parameter setting, remote‑control operation and automatic‑report generation. Multi‑user‑permission management and full‑operation‑event logging are supported for intelligent‑plant‑O&M.

Distributed Secondary‑Level Devices

• These are bay‑local‑mounted protection relays not installed inside PV grid‑connection protection panel, including GWPR300‑series line‑protection relay, transformer‑protection relay, capacitor‑protection relay and PT‑voltage‑monitoring relay. Supporting accessories: pad‑mounted‑transformer measuring‑control terminal, combiner‑box acquisition‑module, on‑site CT/PT sampling‑units and local‑acquisition‑terminals.
• These devices are mounted inside high‑voltage switchgears, pad‑mounted‑transformer‑compartments and capacitor‑bays. Independently perform analog‑quantity acquisition, status‑monitoring, fault‑judgment and local tripping without relying on upper‑level host. They provide full‑scope protection & measurement‑control for lines, main‑transformers, capacitors and bus‑PTs to complete bay‑level‑protection‑coverage. Distributed protection relays work coordinately with Anti‑islanding / Fault Separation Relays inside PV grid‑connection‑protection panel to constitute the complete bay‑level‑protection system.

System Architecture

• Adopting industry‑standard four‑tier hierarchical‑distributed architecture for clear logic, high reliability and good scalability.

Field‑Device Perception Layer (Primary‑Field‑Equipment)

• PV‑modules, inverters, pad‑mounted‑transformers, high/low‑voltage switchgears, circuit‑breakers, PT/CTs, combiner‑boxes, meteorological‑stations and metering‑devices. Responsible for raw‑electrical‑data and environmental‑data acquisition.

Bay‑Level Layer (Protection & Measurement‑Control Layer)

• Composed of distributed GWPR300‑series bay‑protection relays; Anti‑islanding Relay, Fault Separation Relay and power‑quality‑monitoring‑unit inside GWPC‑PVG PV Grid‑Connection Protection Panel; devices housed in GWPC‑TP Main‑Transformer Protection Panel, GWPC‑LP Line Protection Panel and GWPC‑CCM Common Measurement & Control Panel; plus various local‑acquisition‑terminals.
• Performs protection‑judgment, data‑acquisition and local fault‑tripping for all plant‑equipment, acting as the core of system safety. Each protection‑relay makes independent decisions without relying on station‑control‑layer or communication‑network, guaranteeing valid‑protection under worst‑case‑conditions.

Station‑Control‑Layer (On‑Site Plant‑Monitoring)

• Consists of optionally‑selected panels from the thirteen‑panel portfolio. Realizes data‑aggregation, logical‑computation, power‑regulation, alarm‑processing, local‑human‑machine‑interaction, fault‑recording‑analysis and data‑storage for centralized‑plant‑management.
• Small‑scale 0.4kV distributed PV allows station‑control‑layer simplification with partial‑panel‑removal; data can be uploaded to cloud‑platform via 4G/5G. Bay‑level anti‑islanding and safety‑protection functions shall remain fully intact in compliance with GB/T 37408.
  Dispatch & Remote‑Central‑Control Layer
• Uplink‑connection to local‑utility‑dispatch‑master‑station (IEC 60870‑5‑104 / IEC 61850). Uploads protection‑related, measurement‑control, power‑generation and alarm data; accepts dispatch regulation‑commands and meets grid‑dispatch‑access requirements.
• Interfaces with group‑owned remote‑central‑control‑center to realize multi‑plant‑central‑O&M, supporting cross‑plant unified‑alarm, generation‑comparison and O&M‑work‑order dispatching.
• 0.4kV distributed‑plants can connect to cloud‑O&M‑platform for web‑browser and APP‑based plant‑data viewing.
• Architecture highlights: Hierarchical‑distributed design; single‑bay‑device‑failure will not affect other bays. Station‑control‑layer supports optical‑fiber‑ring‑network with high anti‑interference performance; communication self‑healing time ≤ 50ms. High‑voltage‑plants strictly implement power‑security‑zone‑partition and security‑encryption‑authentication. Low‑voltage‑distributed‑solutions support hardware‑simplification for CAPEX‑reduction. Dual‑redundant‑station‑control‑network (PRP/HSR protocol support, standard‑for‑132kV‑booster‑stations, optional‑for‑medium/low‑voltage‑plants) delivers zero‑delay‑switch‑over upon key‑link‑failure. Built‑in communication‑self‑diagnosis continuously monitors device‑network‑status and‑data‑quality.

Application Scenarios

① 0.4kV Low‑Voltage Distributed PV

• Commercial‑industrial rooftop PV, park‑based distributed PV, typical capacity: 8kW‑400kW.
• Realizes grid‑connection‑monitoring, anti‑islanding‑protection, reverse‑power‑monitoring and energy‑statistics. Supports local‑monitoring or cloud‑based‑remote‑O&M. PT‑voltage‑monitoring‑protection‑relay is optional.
• Safety note: Station‑control‑layer hardware may be simplified, while anti‑islanding and safety‑protection functions shall not be reduced, complying with GB/T 37408 and relevant anti‑islanding‑device‑standards.

② 11kV Medium‑Voltage Collection‑Type PV Plant

• Medium‑size ground‑mounted PV, commercial‑industrial boosted‑PV, typical capacity: 400kW‑6MW.
• PV‑arrays are boosted to 11kV via pad‑mounted transformers for grid connection. Full‑scope deployment of distributed‑protection‑relays for lines, transformers, capacitors and PT‑voltage‑monitoring. Matched with GWPC‑PVG PV Grid‑Connection Protection Panel, GWPC‑CCM Common Measurement & Control Panel, GWPC‑AGVC AGC/AVC Control Panel and GWPC‑RTU Remote‑Communication Panel. GWPC‑DFR Fault‑Recording Panel is optional to satisfy grid‑acceptance‑criteria.

③ 33kV Medium‑High‑Voltage Collection‑Type PV Plant

• Medium‑to‑large‑size ground‑mounted PV, commercial‑industrial boosted‑PV, typical capacity: 6MW‑30MW.
• PV‑arrays are boosted to 33kV via pad‑mounted transformers for grid connection. Full‑scope deployment of distributed‑protection‑relays for lines, transformers, capacitors and PT‑voltage‑monitoring. Matched with GWPC‑PVG PV Grid‑Connection Protection Panel, GWPC‑TP Main‑Transformer Protection Panel, GWPC‑CCM Common Measurement & Control Panel, GWPC‑AGVC AGC/AVC Control Panel, GWPC‑PFR Primary Frequency‑Regulation Panel, GWPC‑SPF Solar Power Forecasting Panel, GWPC‑DFR Fault‑Recording Panel and GWPC‑RTU Remote‑Communication Panel. Where outgoing‑transmission‑voltage‑level is 132kV or utility‑dispatch‑access‑to‑dedicated‑dispatch‑data‑network is required, GWPC‑DDN Dispatch Data‑Network Panel plus security encryption gateway shall be added to satisfy grid‑acceptance‑criteria.

④ 132kV High‑Voltage Large‑Scale PV Booster‑Station

• Large‑scale centralized ground‑mounted PV plants, PV plants in mountainous areas, PV‑energy‑storage integrated bases; capacity above 30MW.
• Full‑set secondary‑monitoring‑system. Complete deployment of all distributed‑bay‑protection‑relays, GWPC‑PVG PV Grid‑Connection Protection Panel, GWPC‑TP Main‑Transformer Protection Panel, GWPC‑LP Line Protection Panel, GWPC‑CCM Common Measurement & Control Panel, GWPC‑PFR Primary Frequency‑Regulation Panel, GWPC‑SPF Solar Power Forecasting Panel, GWPC‑DFR Fault‑Recording Panel, GWPC‑DDN Dispatch Data‑Network Panel (standard‑configuration) with security encryption gateway.
• Wide‑band‑oscillation‑monitoring and Grid‑Restore Synchronization Auxiliary Module are optional. Fully meets all technical‑specifications for utility‑grid‑integration of new‑energy‑stations.

⑤ Multi‑Site Central O&M Scenario

• Multiple dispersed PV sites owned by single operator (mixed 0.4kV / 11kV / 33kV);
• GWSC‑PV remote central control platform delivers unified monitoring for multiple plants, unified alarm, generation‑statistics comparison and equipment health‑assessment to reduce on‑site O&M labour cost.

⑥ PV‑Energy‑Storage‑Hybrid Monitoring

• PV‑plus‑energy‑storage‑PCS hybrid‑grid‑connection‑projects. The system can extend to energy‑storage‑equipment (BMS, PCS, EMS). Additional capacitor‑and‑line‑bay‑protection‑relays can be equipped. Realizes coordinated‑PV‑storage‑power‑regulation, peak‑shaving‑valley‑filling and black‑start‑assistance. Supports plug‑and‑play for new‑energy‑storage‑bays.
• Revision Note: Specific protection settings, control strategies and panel configurations can be customized according to actual plant voltage level, installed capacity and local utility requirements. For 0.4kV distributed projects, station‑control‑layer panels may be consolidated or simplified where grid acceptance criteria are satisfied, to reduce capital investment.