Method for operating a converter in a system for generating electrical energy

摘要

Described is a method for operating a converter for a system for generating electrical energy. In an embodiment of the method, the output voltage of the converter is converted to a d, q coordinate system, wherein the d, q coordinate system is assigned to the frequency of the voltage for the energy supply grid. A desired value is furthermore specified in the d, q coordinate system, several momentary or future values are determined from the output voltage in the d, q coordinate system for different switch positions of the converter, deviations between the desired value and the momentary or future values are determined in the d, q coordinate system, and the converter is switched to one of the switch positions in dependence on these deviations.

主权项

1. A method for operating a converter, via a control unit, in a system used for generating electrical energy, the system including a generator operatively connected to the converter which, in tum, is operatively connected to an energy supply grid, the frequency of a voltage generated by the generator being variable and a plurality of different switch positions being realizable with the converter, the method comprising:
converting, in the control unit, voltages responsive to an output from the converter to respective d, q rotating coordinate system voltage trajectories, each being representative of a current voltage value and future voltage values; specifying a desired voltage value matching a frequency of a voltage of the energy supply grid; determining, from the d, q rotating coordinate system voltage trajectories, a closest trajectory having a current value closest to the desired voltage value and switching the converter in dependence on the closest trajectory, the switching being based upon a frequency of the voltage of the energy supply grid; wherein the specifying, the determining, and the switching are recomputed at predetermined time intervals.