Distributed photovoltaic rooftop power generation system lightning protection solution

I. Introduction

Because of the installation location and use environment of distributed photovoltaic power generation systems, the probability of system equipment being exposed to lightning surges is also increasing. At present, the national photovoltaic poverty alleviation project is also vigorously carried out. More and more rooftop photovoltaic power generation systems are affected by lightning strikes. Therefore, research on lightning protection of distributed photovoltaic power generation systems based on actual conditions will help improve the safety and efficiency of the entire power generation equipment system. The operation reduces the cost of operation and maintenance of the project. The lightning protection of the lightning protection system of distributed photovoltaic power generation systems is briefly described in terms of direct lightning protection and inductive lightning protection.

Second, distributed photovoltaic system equipment lightning and over-voltage protection

2.1 The impact of lightning on distributed photovoltaic power generation system equipment is mainly caused by the following aspects:

Direct lightning: Most of the solar panels of the distributed rooftop PV system are installed on the roof of the outdoor area, so lightning is likely to hit the solar panel directly, causing damage to the equipment and thus it cannot generate electricity;

Inductive lightning: Lightning strikes in the distance, due to the spatial propagation of electromagnetic pulses, in solar panels and controllers or inverters, controllers to DC loads, inverters to power distribution panels and switchboards to AC loads, etc. Surge over voltage on the power supply line, damage the electrical equipment;

2.2. Lightning and overvoltage protection of distributed photovoltaic power generation system equipment

The composition of photovoltaic power generation system: A set of basic solar power generation systems consists of solar panels, controllers, inverters and batteries.

2.2.1 Direct lightning strike protection for solar photovoltaic power generation system

The solar panels of distributed rooftop photovoltaic systems are generally on the roof. In this case, lightning may directly shine on the solar panels. If this happens, the damage to the entire system will be enormous, so the solar cells for the roof are The board needs to be protected from direct lightning strikes.

Direct lightning protection systems include lightning receptors (lightening conductors), deflectors, and grounding nets. Separate lightning rods are set up on the roof. Solar panels must consider the effect of lightning rod shadows on the panel when installing lightning rods.