Stable operation of solar power plants even in dew, rain and ice
Around 15 per cent of the electricity generated in Germany comes from photovoltaic systems. The installed photovoltaic capacity now stands at almost 100 gigawatts. A large proportion of this is accounted for by large solar power plants.
It is obvious: electricity from the sun is needed. This makes it all the more important that solar power plants always produce electricity reliably as soon as the sun shines. In order for this to work, a number of challenges must be overcome. This is because morning dew, rain or ice on the modules, as well as natural ageing processes and animal damage, can lead to unwanted delays or even failures.
Read this article to find out how reliable power generation can be ensured in solar power plants.
Loss of revenue due to insulation faults
Weather conditions, brittle cable insulation or animal damage can lead to insulation faults. They are responsible for alarms, delayed connections or even complete failures of solar power plants, thereby reducing the ROI. These faults usually occur gradually or are related to the dynamic conditions caused by outdoor operation.
If solar power plant operators want to avoid delayed connection or even complete failure of their systems, such insulation faults must be detected reliably and safely.
Solution: Insulation monitoring with dynamic measurement
Most solar power plants are operated in unearthed networks (IT system). The use of an insulation monitoring device is therefore mandatory.
Practical experience has shown that insulation monitoring devices with fixed alarm thresholds tend to trigger false alarms, especially when dew, water or ice is present on the solar modules, causing the systems to switch off or not switch on at all, even though safe operation is possible.
An insulation monitoring device is therefore required that can cope with the dynamic conditions described above in PV applications.
The ISOMETER® isoPV1685DP is ideal for this purpose. On the one hand, it is designed for the special requirements of large solar power plants, such as the required voltage of 800 V AC / 1500 V DC and ambient temperatures of up to +70° C. Above all, however, the ability to control the dynamic insulation conditions and the resulting leakage capacities of up to 4000 µF ensures a stable and error-free start-up phase for the systems and thus also higher yields for the solar parks.
Background
Insulation monitoring devices measure the insulation level of PV systems relative to earth. In unearthed networks, all active conductors are insulated from earth. If, for example, moisture causes a low-resistance connection to earth, the PV system can continue to operate without any problems.
Some operators nevertheless switch off the systems when the insulation resistance falls below a certain threshold value, without taking into account that voltage is still present on the DC side as long as light is falling on the panels. A safety-related aspect that must be taken into account during maintenance and troubleshooting.
Read more here about why continued operation is possible in an ungrounded network even after an initial electrical fault.
Act now: Is your solar power plant weatherproof?
Dew, rain and ice can significantly disrupt electricity production at solar power plants – and thus reduce your yields. Check your system for weather-related insulation changes and rely on reliable insulation monitoring. This helps you avoid unnecessary alarms, delayed connections or even failures – and ensures maximum performance in all weather conditions.
Do you have questions about intelligent insulation monitoring of solar power plants? Feel free to contact us. Our experts will be happy to help you.
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