Part 2: Equipment-level inspection and operation and maintenance SOP of PV side bracket and tracking transmission system of photovoltaic power station
This article corresponds to the panoramic topology diagram of the photovoltaic power station [Module 2: Photovoltaic brackets and tracking transmission system]. As the "bones and muscles" of the photovoltaic array, it covers the anti-corrosion of the metal structure of the fixed bracket, review of anchor bolt torque, foundation settlement and pull-out test, flat single-axis/dual-axis tracking bracket gearbox lubrication, drive motor insulation temperature measurement, tracking controller (TCU) inclination angle calibration, and actual measurement of wind/snow Stow protection mode.
1. Fixed support structure, foundation and anti-corrosion maintenance SOP
Fixed photovoltaic brackets (fixed inclination/adjustable inclination brackets) bear self-weight, wind load and snow load for a long time, and the mechanical stability of the structure is directly related to the safety of the entire station.
(1) Maintenance of metal structure and anti-corrosion layer of fixed bracket
Hot-dip galvanized steel bracket anti-corrosion layer inspection and repair:
Check that there is no red rust or powder on the surface of the hot-dip galvanized steel bracket. Use a coating thickness gauge to measure the thickness of the anti-corrosion galvanized layer: the thickness of the galvanized layer must be ≥ 65 μm in ordinary areas and ≥ 85 μm in high salt spray/seaside/coastal areas.
Anti-corrosion paint touch-up SOP (rust repair treatment): If local red rust is found, use a wire brush and 400-grit sandpaper to remove the floating rust until the copper metallic luster is exposed ➔ Wipe clean with isopropyl alcohol ➔ Apply two coats of cold spray zinc/zinc-rich primer (dry film thickness ≥ 40 μm) ➔ Apply two coats of epoxy polyurethane topcoat (dry film thickness ≥ 40 μm), the total thickness of the anti-corrosion layer must be ≥ 80 μm.
Inspection of aluminum alloy and weathering steel brackets:
Aluminum alloy bracket (aluminum alloy 6063-T6): Check that the thickness of the anodized film must be ≥ 15 μm, and there is no white spot pitting corrosion or electrochemical corrosion caused by contact with different metals.
(2) Standard table for review of bracket bolt tightening torque
Operation and maintenance personnel must use calibrated insulated torque wrenches to randomly inspect the key stress-bearing node bolts of the fixed bracket (sampling inspection rate is not less than 20%), and re-tighten the anti-loosening mark line after tightening:
(3) Settlement and pull-out resistance test of support foundation
Inspection of uneven foundation settlement: Check cast-in-place piles, prefabricated cement piers and spiral steel pile foundations. The uneven settlement of adjacent foundations must be < 10.0 mm; check that the soil around the foundation is not eroded by water flow and that there are no cracked or broken piles.
Sampling test of single pile pullout resistance (annual): Conduct sampling pullout test on the foundation (sampling test rate is not less than 1‰). The foundation pullout resistance must comply with the original engineering design value (for example, the pullout resistance of a single pile must be ≥ 15.0 kN).
2. Tracking bracket transmission mechanism (flat single axis/double axis) equipment level maintenance SOP
The tracking bracket (flat single-axis/oblique single-axis/double-axis tracking) can increase power generation by 10% to 25% by aligning with the sun in real time, but its mechanical transmission part is a high-maintenance area.
(1) Maintenance of reduction gearbox (Gearbox) and slewing bearing (Slew Drive)
Oil/grease replacement and replenishment:
Check the oil level gauge of the reduction gearbox. The oil level must be maintained at 1/2 ~ 2/3. Replenish or replace heavy-duty industrial gear oil (such as CKD 220) annually.
Add extreme pressure lithium grease (NLGI grade 2) to the slewing bearing worm gear every six months until the new grease overflows from the oil drain port.
Gear play and bite clearance inspection:
Use a dial indicator to measure the meshing clearance of the slewing bearing gear. The axial and radial clearance must be < 0.50 mm.
If the gearbox emits a "click-click" sound of violent metal dry friction and impact when the motor is running, it indicates that the gear is seriously worn or collapsed, and the gear box must be stopped and replaced.
(2) Drive motor and transmission spindle bearings
Drive motor electrical and temperature rise inspection:
Measure the operating current of the 24V/48V DC or 380V AC drive motor. The operating current must be within the rated current range of the motor (without overload and jamming).
Use a 500V/1000V megger to measure the insulation resistance of the motor winding to ground. It must be ≥ 5.0 MΩ. The motor operating temperature rise must be < 40.0 ℃.
Universal coupling and transmission spindle:
Check that the universal joint bolts of the connecting rod are not sheared and loose, and that the pins are not falling off; check that the main shaft (main beam) is not twisted and deformed; add anti-rust lubricating oil to the rotating bearing slider.
3. Tracking control system (TCU) angle calibration and Stow protection measured SOP
(1) Tracking controller (TCU) angle calibration and inverse tracking algorithm
Tracking angle deviation calibration:
Use an electronic high-precision inclinometer close to the frame of the component to measure the actual inclination of the bracket and compare it with the angle displayed on the TCU screen or SCADA monitoring.
Angle error standard: The deviation between the actual tilt angle and the theoretical astronomical tilt angle must be < 1.5°. When the angle deviation is ≥ 2.0°, it will cause severe "shadow blocking" of the front and rear components, resulting in a power generation loss of > 5%.
Backtracking algorithm calibration:
One hour after sunrise in the morning and one hour before sunset in the evening, check that the reverse tracking algorithm of the tracking system is running normally, and the bracket automatically returns to a gentler angle to prevent the front bracket from blocking the rear components.
(2) Actual measured SOP (forced safety logic) in Stow protection mode in strong wind/snow
When encountering bad weather, the tracking system must automatically switch to Stow (safety tile) protection mode to prevent huge wind resistance from blowing over the bracket.
Measured SOP in strong wind Stow protection mode:
Test cycle: Test once every six months using simulated wind speed signals.
Actual measurement process and response timing:
Step 1: The wind speed and direction instrument of the weather station detects a gust speed ≥ 17.2 m/s (reaching the level 8 wind warning line).
Step 2: The weather station sends a group wind warning broadcast signal to the TCU tracking controller in milliseconds.
Step 3: The TCU controller forcibly interrupts the current sun tracking logic and starts the drive motor.
Step 4: The tracking bracket must quickly rotate to
Heavy snow/hail snow removal protection mode:
When the snow load sensor detects that the snow load thickness is > 10 cm, the TCU controller drives the bracket to rotate to the maximum inclination angle (such as 50 degrees), and uses gravity to automatically slide and unload the snow to prevent heavy snow from collapsing the bracket.
Anemometer loss safety countdown protection:
When the communication interruption between the TCU controller and the main weather station lasts for more than 5 minutes, the TCU must automatically and forcibly control the bracket to cut into the 0-degree horizontal Stow protection position to prevent loss of control and destruction due to communication interruption during sudden strong winds.
Photovoltaic power station PV side bracket and tracking transmission system equipment level inspection and operation and maintenance sign-in form
Power station name: _______________________________ Inspection date: ____ month ____ day, 2026
Inspection area: Photovoltaic bracket and tracking transmission area Inspection person in charge: ____________________
1. On-site equipment inspection and test data recording
2. Inspection defect registration and defect elimination dispatch
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