The operation and maintenance of photovoltaic power stations is a crucial aspect in ensuring the long-term efficient operation and extending the service life of the system, directly impacting the return on investment:
1. Construction of operation and maintenance system
Selection of operation and maintenance mode:
Independent operation and maintenance: suitable for large-scale power stations (≥10MW) or enterprises with mature operation and maintenance teams, with low long-term costs
Third-party operation and maintenance: suitable for small and medium-sized power stations, with professional teams providing services to lower the technical threshold
Intelligent operation and maintenance: By combining remote monitoring with regular inspections, we can reduce labor costs and improve response speed
Operation and maintenance team configuration:
Large ground-mounted power stations: 1-2 professional operation and maintenance personnel per 50MW
Distributed project: 1 inspector is allocated for every 100 sites, supplemented by remote monitoring
Operation and maintenance management system:
Routine inspection: Conduct once a week to check the status of components, brackets, inverters, and other equipment
Regular maintenance: once a month, clean components, tighten screws, and check electrical connections
Quarterly/Annual Maintenance: Conduct a comprehensive inspection, test the protective device, clean the components, and calibrate the tracking system
Fault handling process: discovery → reporting → analysis → repair → verification → recording, forming a closed loop
2. Key points of daily maintenance
Component maintenance:
Cleaning frequency:
Dusty areas: once every 2 weeks
General areas: Once a month
In rainy areas: 1-2 times per quarter
Cleaning method:
Soft cloth/sponge + neutral detergent, avoid scratching the glass with sharp tools
High-pressure water gun washing (pressure < 0.3MPa), suitable for large-area cleaning
Avoid rinsing with cold water when the component temperature is > 40℃ to prevent thermal stress damage
Inspection items:
Is there any damage, crack, or discoloration (yellowing) on the surface of the component
Is there any bubble or delamination in the packaging
Is there any deformation, cracking, or signs of overheating on the junction box
Support system maintenance:
Fastener inspection: Conduct once every quarter, retighten loose screws, especially for the rotating parts of the tracking system
Preservation and maintenance:
Apply anti-corrosion paint to the damaged areas of the hot-dip galvanized layer to ensure a service life of over 25 years
Inspect the anti-corrosion condition in coastal areas every six months, and enhance protection measures when necessary
Tracking system maintenance:
Regularly clean the rotating parts and add lubricant to ensure smooth operation
Check the limit switch and angle sensor to ensure tracking accuracy
Inverter maintenance:
Cooling system: Clean the cooling fan and filter screen monthly to prevent dust accumulation from affecting heat dissipation
Electrical connection: Inspect the terminal strip quarterly to ensure there are no signs of looseness, oxidation, or overheating
Software update: Regularly upgrade the inverter firmware to optimize performance and functionality
Fault record: Save historical fault data, analyze patterns, and take preventive measures in advance
3. Common fault diagnosis and handling
Common faults and handling of components:
Fault Symptom    Possible Cause    Solution    Preventive Measure
Module power degradation: Dust obstruction (loss of 5%-15%) Regular cleaning, choose easy-to-clean glass Installation angle ≥15°, reduce dust accumulation
Hot spot effect: Individual solar cell damage or obstruction. Replace damaged components and avoid partial obstruction. Implement component-level protection and conduct regular inspections
Module water ingress, encapsulation failure, and backplane damage. Replace the module and check the installation for any damage to the backplane. Select high-quality modules to avoid installation damage
PID effect (power dip)    Poor system grounding, high humidity environment    Improve grounding, select anti-PID components    Conduct PID testing before installation, select N-type batteries
Common faults and solutions of inverters:
DC overvoltage/undervoltage:
Reason: Improper component configuration, grid voltage fluctuation
Solution: Check whether the number of components connected in series falls within the MPPT range of the inverter, and adjust the configuration accordingly
Island protection action:
Reason: abnormal power grid or protection malfunction
Handling: After confirming that the power grid has returned to normal, manually reset and check the protection parameter settings
Over-temperature protection:
Reason: Poor heat dissipation, high ambient temperature
Solution: Clean the cooling fan, improve ventilation conditions, and add cooling devices if necessary
Support system failure:
The tracking system is stuck:
Reason: mechanical failure, abnormal limit switch, motor failure
Treatment: Check mechanical connections, clean rotating parts, and replace damaged motors
Support deformation / tilt:
Reasons: foundation settlement, excessive wind load, material defects
Treatment: Reinforce the foundation, replace damaged parts, and strengthen wind resistance measures
4. Performance optimization and improvement
Measures for optimizing power generation:
Module cleaning: Regularly removing dust can increase power generation by 5%-15%
MPPT optimization:
Ensuring that the inverter operates at the optimal MPPT point can increase power generation by 3%-8%
The multi-string system ensures that strings with the same orientation/inclination are connected to the same MPPT, reducing mismatch losses
Component matching:
The power difference among components in the same string is less than 3%, avoiding the "cask effect"
When replacing damaged components, try to choose components of the same model or with similar parameters
Temperature management:
Improving the ventilation conditions of the inverter, for every 10℃ decrease in temperature, the efficiency increases by 1% and the lifespan extends by 50%
Leave sufficient clearance for component installation to improve heat dissipation
System efficiency evaluation:
PR value (Performance Ratio) evaluation: PR = Actual power generation / (Theoretical power generation × System efficiency)
Excellent system: PR>0.85
Good system: 0.8<PR≤0.85
System to be optimized: PR<0.8
Loss analysis:
Line loss: normal < 5%, if too high, check cable specifications and connections
Temperature loss: normal < 10%, excessive requires improved ventilation and heat dissipation
Dust loss: normal < 5%, if too high, increase cleaning frequency
5. Full lifecycle management
Equipment replacement strategy:
Component replacement:
When the power attenuation exceeds 20%, consideration should be given to an overall replacement, typically after 15 to 20 years
Replace individual damaged components in a timely manner to avoid affecting the entire string
Inverter replacement:
Consider replacement when efficiency drops by more than 5% or frequent malfunctions occur. The typical lifespan is 10-15 years
Support system maintenance:
The lifespan of the hot-dip galvanized coating is 25 years or more, and it generally does not require replacement
Regular anti-corrosion treatment is applied to key nodes to extend their service life
Data management and analysis:
Establish a database to record equipment parameters, maintenance records, fault handling, power generation data, etc
Performance analysis:
Year-on-year analysis: Compared with the same period last year, seasonal and systematic changes were observed
Month-on-month analysis: Compare with the previous month to promptly detect abnormal fluctuations
Horizontal comparison: Compare similar power stations within the same region to identify gaps and areas for improvement
Operation and maintenance suggestions: Establish an operation and maintenance system that prioritizes prevention and integrates prevention with control. Leverage intelligent monitoring systems to enable remote diagnosis and early warning, conduct regular performance evaluations and optimizations, ensure long-term efficient and stable operation of photovoltaic power plants, and maximize return on investment