Design Basis

GB50057-2010 "Building Lightning Protection Design Code"

GB50343-2004 "Building Electronic Information System Lightning Protection Technical Specifications"

QX3-2000 "Weather Information System Lightning Strike Electromagnetic Pulse Protection Specification"

GB18802 "Surge Protector (SPD) for Low Voltage Distribution System"

IEC61312-1, 2, 3 "Protection of Lightning Electromagnetic Pulses"

GB50169-92 "Code for Construction and Acceptance of Grounding Device for Installation of Electrical Installations"

GB50194-93 "Safety Specifications for Power Supply and Use at Construction Sites"

At present, global energy shortages, people are increasingly using new, green, environmentally friendly energy as a supplement and substitute for traditional energy, solar energy is one of them. Solar energy is the most important basic energy source of all kinds of renewable energy. Solar power generation is a typical green energy-saving energy source. It is safe, reliable, noise-free, pollution-free, geographically independent, fuel-free, low failure rate, and maintenance. Convenient, scale and free to combine with buildings. It has gradually gained recognition from everyone with its unique advantages.

    As an emerging power generation system, solar photovoltaic power generation system has attracted much attention and wide application in the field of energy power generation. Due to the special installation location and environment of solar photovoltaic power generation system, the hidden danger of lightning damage caused by lightning electromagnetic pulse is also coming. The more prominent.

Therefore, the research on lightning protection of solar photovoltaic power generation system according to the actual situation helps to improve the safe and efficient operation of the entire power generation equipment system.

First, the invasion path of lightning electromagnetic pulse interference

     The impact of lightning on solar photovoltaic system equipment is mainly caused by the following aspects:

     Direct lightning: Most solar panels are installed on outdoor roofs or in open spaces, so lightning is likely to hit solar panels directly, causing damage to the equipment and thus failing to generate electricity;

     Conducted lightning: lightning strikes in the distance, due to the spatial propagation of electromagnetic pulses, will be in solar panels and controllers or inverters, controllers to DC loads, inverters to power distribution panels and switchboards to AC loads, etc. Surge overvoltage on the power supply line, damaging electrical equipment;

    Ground potential counterattack: In a solar power supply system with external lightning protection, because the external lightning protection device introduces lightning into the earth, the high voltage is generated on the ground, and the high voltage enters the device through the grounding wire of the device, thereby damaging the controller and counter The transformer is either a device such as an AC or DC load.

Second, solar photovoltaic grid-connected power generation system integrated lightning protection program

The basic components of solar photovoltaic grid-connected power generation systems are: solar cell array, DC distribution cabinet, AC power distribution cabinet and inverter. The solar cell array is made of metal material and occupies a large space and is generally placed on the top of the building or in an open area. In the event of a thunderstorm, it is particularly vulnerable to lightning strikes, and the solar cell module and the inverter are relatively expensive to avoid Lightning strikes and surges cause economic losses, and effective lightning protection and surge protection are essential. The main measures for lightning protection of solar photovoltaic grid-connected power stations are:

Third, solar photovoltaic power system lightning protection device selection configuration

     Surge protection is mainly achieved by installing a lightning arrester SPD on the live cable to reduce damage caused by surge and lightning overvoltage. The lightning surge intrusion path of solar photovoltaic grid-connected power generation system, in addition to the solar cell array, there are distribution lines, grounding lines, etc., so the solar photovoltaic grid-connected power generation system needs to take the following protective measures:

1. Install Kiloamp PV DC lightning arrester KPD1200-40YYR, 40kA (8/20μs) in the PV combiner box.

2. Install Kiloamp PV DC lightning arrester KPD1200-40YYR, 40kA (8/20μs) at each DC input of the inverter.

3. Install Kiloamp three-phase AC lightning arrester KPB385-4040R, 40kA (8/20μs) on the AC side of the AC power distribution cabinet.