Protection circuit for an inverter as well as inverter system

摘要

A protective circuit for an inverter is disclosed, the protective circuit comprising a safety element, a switching arrangement, and a control circuit, with the safety element being arranged in a feed line to the power element, and the switching device being switched to the safety element such that the switching arrangement bridges the safety element when the switching arrangement is in a conducting state. The control circuit is embodied such that it, upon receipt of one control pulse or several successive control pulses, emits a switching signal to a switching arrangement for a predetermined period of time, with the switching arrangement being switched through in case of periodic receipt of the control pulses and with the absence of the control pulse opening the switching arrangement after a predetermined period of time, and triggering a protection of the inverter by the safety element.

主权项

1. A protection circuit for an inverter, particularly for an inverter for an electric motor, with the inverter comprising a control system and a power component controlled by the control system, and with the control system being configured for the periodic output of a control pulse (WD1, WD2), the protective circuit comprising:
a safety element (3), a switching arrangement (4), and a control circuit (2), wherein:
the safety element (3) is arranged in a feed line to the power component,the switching arrangement (4) is connected to the safety element (3) such that the switching arrangement (4) bridges the safety element (3) into a switched-through state when the switching arrangement (4) is in a conducting state,the control circuit (2) comprises a control input (8, 8′), at which the control pulse (WD1, WD2) is applied, andthe control circuit (2) is configured such that the control circuit (2), upon receipt of a control pulse (WD1, WD2) or several successive control pulses (WD1, WD2) outputs for a predetermined period of time a switching signal to the switching arrangement (4), causing the switching arrangement (4) to: switch through when periodically receiving the control pulse (WD1, WD2), and to, in the absence of the control pulse (WD1, WD2), open after a predetermined period and trigger a protection of the inverter by the safety element (3).