Determining the life of an energy storage device of an uninterruptible DC power supply unit

摘要

The invention relates to a method for determining the capacity of an energy store (A1, A2) of a DC power supply unit for uninterruptible supply of a load (L) with direct current, wherein the DC power supply unit at least - an input (E) for an input voltage, - an output (A) for a DC output voltage, - two similar energy storage (A1, A2), which provide a substitute output DC voltage in buffer mode includes. In order to be able to determine the actual capacity without jeopardizing a buffer operation, it is provided that in a first step, a charged first energy store (A1) is completely discharged via a load (L) present at the output (A) at predetermined time intervals a second step, the first energy store (A1) from the fully charged second energy storage (A2) is loaded, and that in a third step, the second energy store (A2) via the input (E) is fully charged again, in the second step, the the capacitance removed from the second energy store (A2) is measured and / or the capacitance charged into the second energy store (A2) is measured in the third step.