Energy production plant equipped with power conversion unit

Abstract

This application describes an energy production plant comprising a power conversion unit (20) for connection to a PV generator, the PV generator comprising a plurality of PV main strings (PVn) connected in parallel, each PV main string connected to the power conversion unit (20) of the PV energy production plant via two DC input lines on the input side via a DC link circuit (7), the DC link circuit (7) of the power conversion unit (20) being electrically isolated. A monitoring unit (21.n), including a differential current measuring device (8.n), a disconnector (9.n), and a controller (17.n), is assigned to each pair of DC input lines assigned to the PV main strings (PVn). The controller (17.n) of the monitoring unit (21.n) is configured to switch the disconnector (9.n) to isolate the PV main strings (PVn) after a fault is identified due to a differential current threshold being exceeded. At least one predetermined discharge capacity (31, 32) relative to ground is provided on at least one pole of the DC link circuit (7) as a feedback path (35) for measuring the ground current by the differential current measuring device (8.n).

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