Services for solar photovoltaic energy

Manufacturing - QC services at source

It is a reality that the Asian continent currently dominates the production of the main components for photovoltaic installations.  This fact means that there are geographical, language and cultural barriers that in many cases are insurmountable. At Apave International Group, we have local collaborators to carry out inspections with duly qualified personnel who are familiar with both Asian and Western customs.

• Assistance in negotiating manufacturer-supplier contracts
• Factory audits and manufacturing supervision
• Pre-shipment inspection of equipment and containers

Reception at the plant

Reception is a stage of the process that is rarely considered as an integral part of it; however, its correct execution is of vital importance, as the useful life of the main components of the installation will depend on it.

• Material reception and acceptance tests in the field
• Electroluminescence testing of PV modules

Since a solar cell is a pn-junction, if an electric current is applied at the terminals, a cell will function as a light-emitting diode. In an El image, cells that do not emit photons will appear dark and these will be the ones that are faulty. It is necessary to perform this test in the dark.

This detection technique is widely used both when starting up the installation (to check that after assembly and transport, the cells remain unbroken) and for predictive maintenance during the lifetime of the plant. For this method, a camera with a sensitivity between 900 and 170 nm is needed, which can be a normal thermographic camera, with a change of filter or a camera already prepared for this type of work.

For the reception of on-site modules, we have our own technology from one of our partners that allows us to measure each module with a portable laboratory. And for modules already installed, we have another innovative technology that allows us to carry out the measurement without dismantling the modules and to operate during the day.

Flash Test on-site with portable laboratory (IEC 61215: 2021)

Flash tests measure the output performance of a solar photovoltaic module and are a standard test procedure used by manufacturers to ensure that each photovoltaic module is operationally compliant. During the so-called flash test, the module is flashed with a calibrated flasher. The electrical output is measured and the power is determined under standard test conditions (STC).

It is performed according to IEC 61215: 2021 Terrestrial photovoltaic (PV) modules - Design qualification and type approval. Part 1: Test requirements and Part 2: Test procedures.

For the acceptance of on-site modules, we have our own technology from one of our partners that allows us to measure each module with a portable laboratory.

Installation and assembly

We have more than 45 years of experience in providing comprehensive services in the areas of inspection, quality control, quality assurance and occupational risk prevention. This allows us to offer integrated solutions to our clients, whatever their size and geographical location.

• Assistance to site management
• Civil, mechanical and electrical supervision
• Health and safety co-ordination / preventive resources
• QA/QC. On/off site quality control and management

Commissioning

To carry out the commissioning after the construction of the PV plant, it is essential to ensure that the installation was carried out in a safe and reliable way. Apave performs field measurement services, following the tests detailed below, to ensure the correct operation of the installation.

Tests UNE EN 62446-1. Requirements for testing, documentation and maintenance. Documentation, start-up tests and inspection:

- Category 1 tests

• Continuity of earthing protections
• Polarity, open circuit voltage and short circuit current
• PV generator insulation resistance

- Category 2 tests

• Curve IV of the strings, PV generator efficiency

This is a current and current measurement under real operating conditions, which is then extrapolated to form the IV curve under non-STC (standard test conditions; 25°C and 1000 W/m2). With this method, important parameters such as short-circuit current, open-circuit voltage and operating point at maximum power are defined. In this way, the variation of the curve as a function of temperature, irradiance and series and parallel resistance of the module will give information about possible defects in the module string.

Thermographic inspection with drones

Thermography is currently the most widely used method for inspecting PV modules, as it is carried out instantaneously without interfering with the operation of the installation. The light incident on the cell generates heat, which is detected by the infrared of the camera. Normally, this temperature does not vary much between optimally functioning cells, however, when a cell has an increase in electrical resistance the temperature increases.

Additional tests (wet insulation, blocking diodes)

Additional tests on Medium Voltage electrical installation:

• Insulation testing by Partial Discharge (VLF).
• Measurements of earthing resistance and step-contact voltages.