Clir | Renewable Energy Optimization and Reporting Software

Transformer health

Transformers have few moving parts and are generally very reliable machines if maintained properly. However, transformers do age and deteriorate like any other equipment, and this can be accelerated by factors such as hostile environments, overload, or severe duty cycles. Transformers are expensive, and repairs are costly and time-consuming, so monitoring and maintaining transformer health is an important part of optimizing the performance of any power plant. Even with protection and control schemes in place, faults will be experienced by the transformer, so monitoring transformer health is critical.

Module health

The modules at a solar plant are the power source, and their health is a key factor in the performance of the plant. A number of degradation and failure mechanisms can reduce the performance of the panels compared to their nameplate ratings, impacting the performance of the strings and entire array. As the health of a single module may limit the performance of all modules in the string, a single module can have a disproportionate effect on plant performance and it is important that string, module, and array health is monitored.

Typical areas of failure are:

Module encapsulation, delamination, discoloration, and other physical damage.

Wiring and connector issues.

Loose or oxidized Junction Box.

Faulty Bypass Diode.

Cracked, degraded and failing cells within the modules.

Inverter health

Inverters are in many ways the heart and/or brains of a solar plant, and have two critical roles:

Convert the direct current (DC) power generated by the solar modules into grid-compliant alternating current (AC).

Maximize the power output of the solar arrays connected to the inverters by controlling the array voltage to keep the array operating at its most efficient point (its maximum power point) - known as Maximum Power Point Tracking (MPPT).

Proper inverter installation and subsequent monitoring and maintenance of their health helps ensure their reliable and efficient operation. The health of the following components in particular should be considered:

Cooling system.

Capacitors.

Insulated-gate bipolar transistors (IGBTs).

Protection circuits.

Asset health issues

Clir can identify long-term environmental exposure risks by detecting performance anomalies or degradation of plant components. These risks include:

Thermal cycling causing solder bond failures and cracks in modules.

Damp heat, delamination of encapsulants, and corrosion of cells.

Humidity freeze leading to failed junction box adhesion.

UV exposure, discoloration and back sheet degradation.

Frost heave.

Acid Rain.

Hail.

Real-time monitoring

Real-time monitoring of solar plant performance metrics can allow the operator to identify failures and sub-optimal performance more quickly than periodic performance reviews can, reducing response time and so allowing these issues to be corrected sooner, avoiding unnecessary lost revenue.