Method for operating an electric circuit

摘要

The method involves providing an electric circuit with a three-phase power converter (10), which includes series circuits (11-13) with four insulated gate bipolar transistors (IGBTs). The electric circuit is provided with capacitors (Cd1, Cd2), which are connected in parallel to the series circuits. A resistor i.e. symmetrical resistor (Rsym), is connected in parallel to middle IGBTs in the power converter. One of the IGBTs is conductively connected. A discharge current is produced from the capacitors via the conductively connected IGBT and the resistor. The power converter is a three-level-neutral point clamped-power converter. An independent claim is also included for an electric circuit.