Method and apparatus for operating a converter circuit having plural input and output phase connections and plural two-pole switching cells

摘要

A method and apparatus are provided for operating a converter circuit, which includes n input phase connections and p output phase connections, where n≧2 and p≧2, and (n·p) two-pole switching cells for switching at least one positive and negative voltages between the poles. Power semiconductor switches of the switching cells are driven a drive signal. To reduce undesired circulating currents and adjust the mean voltage deviation of capacitive energy storage of all the switching cells to zero, an inductance is connected into each series connection, with a switching cell together with an inductance in each case forming a phase module. For each phase module, the drive signal is formed from a reference signal based on the voltage across the phase module and from a voltage signal across the inductance. The voltage signal is formed from an intermediate setpoint value of the current through the phase module.

主权项

1. A method for operating a converter circuit, wherein the converter circuit includes n input phase connections and p output phase connections, where n≧2 and p≧2, and (n·p) two-pole switching cells for switching at least one positive and at least one negative voltage between the poles, wherein each output phase connection is connected in series to each input phase connection by means of a switching cell, respectively, and each switching cell having drivable bidirectional power semiconductor switches with a controlled unidirectional current guidance direction, and a capacitive energy storage means, wherein the method comprises:
driving the power semiconductor switches of the switching cells by means of a drive signal; connecting at least one inductance into each series connection, with a switching cell together with an inductance in each case forming a phase module; for each phase module, forming the drive signal from a reference signal in respect of a voltage across the phase module and from a voltage signal across the inductance; and forming the voltage signal across the inductance from an intermediate setpoint value of the current through the phase module.