Part 6: Photovoltaic power station PV side station area environment and station auxiliary system equipment level inspection and operation and maintenance SOP)
This article corresponds to the panoramic topology diagram of the photovoltaic power station [Module 6: Station environment and station auxiliary systems]. As an auxiliary base for power station operation and security, it covers station perimeter security, flood control drains, flood control baffles, weed blocking and mowing, station AC power distribution system, ATS dual power automatic switching, station DC panel/UPS uninterruptible power supply and station-level fire control main screen.
1. Station area perimeter security, flood control and vegetation protection SOP
The physical environment and security facilities in the station area are the first barrier to protect the power station from external damage, flooding and shadow blocking.
(1) Station area perimeter security and video surveillance system
Perimeter security and electronic fence inspection: The metal fence around the checkpoint area is not collapsed or damaged, the electronic fence/infrared intrusion alarm system is normal, and the high-voltage pulse host has no alarm.
Video surveillance camera gun cleaning and focusing: Check the full-station dome camera and gun camera lenses, and remove dust, spider webs and bird droppings on the lenses; test the pan-tilt rotation and optical zoom functions to ensure that there are no monitoring blind spots in key areas (high-voltage switch room, boost transformer area, main control room).
(2) Flood control drainage system and flood control baffles
Dredge the drainage ditches in the station area: Check the flood control drainage ditches in the station area and between the rows of the square arrays, and remove weeds, sediment and garbage in the ditches to ensure that accumulated water is drained quickly during heavy rain seasons and prevent the square arrays and equipment foundations from being soaked by water.
Basic flood control baffles and sandbag reserves: Check that the flood control baffles (made of aluminum alloy/stainless steel, height ≥ 500 mm) at the entrance of the high-voltage switch room, flow converter cabin, and main control room are installed smoothly and the sealing strips are intact; the flood control emergency sandbags are sufficient and stacked properly.
(3) Photovoltaic array weeds and tree blocking and mowing SOP
Weed height control: Cut the weeds in the front rows and between rows of the photovoltaic array regularly every month, and control the weed height below the height of the lower edge of the module (usually < 30 cm).
Tree shadow removal: Check the surrounding trees around the power station and promptly prune branches that have grown beyond the standard to ensure that there is no tree shadow blocking the square array throughout the day (especially at 08:00-10:00 in the morning and 15:00-17:00 in the evening when the sun is low) to prevent component hot spot failures caused by local shading.
2. Maintenance SOP for station auxiliary AC power distribution system and ATS dual power supply switching
The station power system provides AC 380V/220V auxiliary power for the entire station lighting, monitoring, fire protection, water pumps and inverter fans.
(1) Inspection of station dry-type transformers and AC distribution cabinets
Station transformer inspection: Check the three-phase winding temperature of the dry-type station transformer (such as 35kV/0.4kV) temperature controller. The winding temperature must be < 80.0 ℃; the automatic start and stop function of the cooling fan is normal.
Temperature measurement and tightening of AC power distribution cabinet: Use an infrared thermal imaging camera to scan the incoming and outgoing terminals of the main circuit breaker. The operating temperature must be < 60.0 ℃, and the three-phase temperature difference ΔT ≤ 5.0 ℃. During annual power outage maintenance, use a torque wrench to retighten the main busbar bolts of the distribution cabinet (M10 torque: 38 ~ 42 N·m).
(2) ATS dual power automatic transfer switch test SOP
ATS (Automatic Transfer Switch) is responsible for automatically switching between main station power and backup power supply (or diesel generator), and must ensure absolute continuity of auxiliary power supply.
Test cycle: Conduct a simulated power cut test every six months.
测试步骤：
Step 1: Confirm that the station DC panel and UPS are supplying power normally to ensure that the relay protection does not lose power.
Step 2: Manually disconnect the main station power incoming line circuit breaker (simulating the main station power loss).
Step 3: Observe the ATS action: The ATS must automatically switch to the backup power supply side within < 100 ms, and the backup loop power supply indicator light turns on.
Step 4: The water pump, air conditioner and fire engine at the inspection station run smoothly and restart without tripping.
Step 5: Close the main station power circuit breaker, and the ATS will automatically switch back to the main power supply side after a delay of 5 seconds.
3. Station DC panel and UPS uninterruptible power supply maintenance SOP
The DC panel (DC 220V/110V) and UPS system are the "last life-saving power supply" for circuit breaker opening and closing and relay protection when the entire station loses power.
(1) DC panel lead-acid/gel battery pack inspection
Single cell float voltage detection: Use a digital multimeter to measure the single battery (12V nominal) float voltage. The qualified range is 13.50 V ~ 13.80 V (at 25 ℃ environment). If the cell voltage is < 13.20 V, it means the battery is undercharged or has an internal short circuit.
Battery internal resistance test: Use a battery internal resistance meter to measure. When the internal resistance of a single battery increases > 25% from the initial value, the single battery must be replaced to prevent a bad battery from bringing down the entire battery pack.
Insulation monitoring: The DC panel insulation monitor shows that the insulation resistance of the positive/negative busbar to ground must be ≥ 0.2 MΩ (220V system).
(2) Inspection of UPS uninterruptible power supply system
Panel status check: Check the UPS control panel to confirm that it is in the "Inverter Mode". It is strictly prohibited to stay in the bypass power supply state for a long time.
Load rate control: The actual output power of the UPS is controlled between 30% ~ 70% of the rated capacity to prevent overload or light load operation.
4. Station-level fire control main screen (FACP) and fire warning maintenance SOP
(1) Fire Alarm Control Panel (FACP - Fire Alarm Control Panel) self-test
Operation status check: Check the fire control main screen (FACP) in the main control room to confirm that there are no "fire alarm", "fault" or "shielding" yellow and red indicators; the backup battery of the main screen is in a fully charged state.
Automatic main/backup power switching: cut off the FACP AC main power supply, the main screen must be seamlessly switched to the backup battery power supply and the continuous monitoring time is ≥ 24 hours.
(2) Probe self-test and manual/automatic control mode
Self-inspection of smoke and temperature probes: Check randomly that the smoke and temperature probe indicators in the high-pressure chamber and main control room are flashing normally.
Control mode key position: The "manual/automatic mode" selection key on the fire control panel must be fixed in the "Auto" position all year round.
Photovoltaic power station PV side station area environment and station auxiliary system equipment level inspection and operation and maintenance sign-in form
Power station name: _______________________________ Inspection date: ____ month ____ day, 2026
Inspection area: Station area perimeter, power distribution room and main control room Inspection person in charge: ____________________
1. Field equipment inspection and test data records:
2. Registration of inspection defects and dispatch of work to eliminate defects
3. Inspection sign-in and review signature
Inspection Engineer (Signature): _______________ Supervision Engineer (Signature): _______________
Review (signature) of the shift leader: _______________ Sign-in and filing time: ____ hour on ____ month ____ day 2026