The characteristics of dc cable and its selection design of pv system

Update date:2017-12-11 Source:MAXGE

Dc mains photovoltaic modules system after pv junction box bus transmission lines to the inverter, if the inverter is the heart of the square matrix system, then dc mains system is the aorta. Due to the dc mains system USES no grounding scheme, if cable grounding fault occurs, will bring to system or equipment of communication is much more than harm, so understanding of dc main cable, pv systems engineer electrical engineer more cautious than any other industry. Through the analysis of all kinds of cable accidents, we conclude that the grounding fault of cable occupies 90-95% of the whole cable fault.


There are three main reasons for grounding fault.

First, the cable manufacturing defect, for non-conforming products;

Second, the operating environment is bad, natural aging, and the damage of external forces;

Third, the installation is not standard, the wiring is coarse.


The root cause of the grounding fault is only one -- cable insulation material. The operating environment of dc main line of photovoltaic power station is very bad. The large ground power stations in China are generally in the west. These places are generally deserts, saline-alkali areas, and diurnal temperature difference, and the rats are also more serious, and the environment can be very humid. The cable is buried and the cable trench is high. The running environment of distributed power cable is better than the above ground, cable can bear high temperature, there are technical personnel measurement and control, the roof temperature can reach 100-110 ℃ high temperature, even cable fire retardant requirement, and high temperature had a great influence on the insulation of the cable breakdown voltage.



Copyright© 2017 All Rights Reserved.

Copyright© 2017 All Rights Reserved.







We won't share your info with third parties.