ATN-400 Automation Solution for Photovoltaic Power Systems

The AutomationSolution for Photovoltaic Power Systems serves as the core technical framework to ensure the safe, stable, and efficient grid-connected operation of power plants.

This solution for grid-connected photovoltaic power systems must adhere to the fundamental principles of power system protection—Reliability, Selectivity, Sensitivity, and Speed—and requires specialized design tailored to the unique operating characteristics of photovoltaic power systems.

Automation Solution for Photovoltaic Power Systems & Protection Relay Configuration List

No.	Protected Object	Equipment Name	Main Function	Configuration Requirement
1	Outgoing Line	Line Protection Relay	Three-zone distance protection, four-zone ground distance, zero-sequence directional overcurrent, pilot differential (fiber channel), autoreclosing, two-end fault location	Fiber optic differential protection for 110kV and above; directional overcurrent and distance protection for 35kV
2	Busbar	Busbar Protection Relay	Busbar differential protection, breaker failure protection	Independent busbar protection for 110kV and above; 35kV busbar protection can be integrated into bay protection
3	Main Transformer	Main Transformer Protection Relay	Differential protection (with inrush identification and CT disconnection blocking), composite voltage blocking overcurrent, zero-sequence overcurrent, gap protection, overload alarm	Dual configuration; selection based on capacity
4	Main Transformer	Non-Electrical Protection Relay	Non-electrical protection for oil temperature, gas, pressure, etc.	Independent device or integrated into main transformer protection
5	Feeder / Collector Line	Feeder Protection Relay	Three-stage overcurrent protection, zero-sequence overcurrent, inverse time overcurrent, small current grounding fault line selection, autoreclosing	Configured for 35kV/10kV collector lines; small current grounding fault line selection function required
6	Collector Busbar	Collector Busbar Protection Relay	Busbar differential protection	Configurable as needed; bus fault isolation can be achieved via feeder protection
7	Unit Transformer	Unit Transformer Protection Relay	Overcurrent protection, overload protection, zero-sequence overcurrent, non-electrical protection	Integrated protection and control device installed at HV side of pad-mounted transformer
8	Inverter	Inverter Protection	Anti-islanding protection, over/under voltage protection, over/under frequency protection, reverse polarity protection	Integrated inside inverter
9	SVG (Reactive Power Compensation)	SVG Protection Relay	Overcurrent protection, overload protection, overvoltage protection, ground fault protection	Configured for 35kV/10kV SVG branch
10	Grounding Transformer	Grounding Transformer Protection Relay	Overcurrent protection, zero-sequence overcurrent protection, overload protection	Configured as needed
11	Station Service Transformer	Station Service Transformer Protection Relay	Overcurrent protection, overload protection, zero-sequence overcurrent protection	Integrated protection and control device
12	Point of Common Coupling (PCC)	Anti-Islanding Protection Relay	Passive islanding detection (voltage/frequency anomaly), active islanding detection, reverse power protection, frequency sudden change tripping, automatic reclosing when voltage returns	Independent anti-islanding protection relay required; operating time ≤2s; reverse power protection required (for non-reverse power grid connection mode)
13	Common Equipment	Fault Recorder	Records fault waveform data (COMTRADE format), collects station-wide fault information	Configured for 110kV and above step-up substations
14	Common Equipment	Small Current Grounding Fault Line Selection Device	Selects faulty line for single-phase ground fault	Configured for 35kV/10kV neutral ungrounded or resonant grounded systems
15	Common Equipment	Automatic Transfer Switch (ATS)	Automatic backup power switching	Configured for station service power system
16	Common Equipment	Power Quality Monitoring Device	Harmonic monitoring (THD, inter-harmonics), voltage fluctuation and flicker monitoring (Pst), three-phase unbalance monitoring	Configured per grid requirements

Safety Automatic Devices Configuration List

No.	Equipment Name	Main Function	Configuration Requirement
1	Stability Control Device	Under-frequency load shedding, under-voltage load shedding, over-frequency generator tripping	Configured per grid dispatch requirements
2	Frequency and Voltage Emergency Control Device	Automatically trips partial generation units or loads during abnormal frequency/voltage conditions	Configured per grid requirements
3	AGC System	Receives dispatch commands, automatically adjusts active power output of PV station	Required for grid-connected PV stations
4	AVC System	Automatically adjusts reactive power compensation devices to maintain voltage stability at PCC	Required for grid-connected PV stations
5	Fault Ride Through (FRT) Monitoring Device	Monitors and records LVRT/HVRT process waveforms	Configured per grid requirements

We are engaged in the power relay protection industry, with years of in-depth experience in the photovoltaic sector. The Automation Solution for Photovoltaic Power Systems we provide delivers professional, tailored PV automation services for clients.