Qualification-testing of lightning current arresters used in DC power supply and photovoltaic systems

Qualification-testing of surge protective devices (SPDs) for the protection of DC power supply and photovoltaic systems requires a test setup that offers the possibility to stress the SPD with defined surge current impulses while connected to a power supply having the same electrical characteristic than the real DC power supply system in which the SPD should operate. This is because of the fact the electric properties of a power supply system can affect the operation behaviour of SPDs significantly. The work presented describes a test setup which is especially developed for these purposes. The approach adopted includes a technical solution for decoupling the surge current generator from the DC power supply which demands a specific designed surge current generator. Technical aspects to be taken into account during the development and operation of such a system are discussed. In addition to this, tests with different types of lightning current arresters are carried out, to demonstrate the performance of the developed test circuit and also to assess the suitability of these arresters for the use in DC power systems.