Patent ID: 8351233

Claim:
A method for closed-loop control of at least two converters in the field of power transmission and/or distribution, the method which comprises: providing the converters in the form of self-commutated converters having power semiconductors that can be turned off, and wherein the converters can be controlled as rectifiers or inverters and are connected to one another via a DC voltage link; measuring a measurement DC voltage and a measurement direct current at each converter and transmitting to a rectifier regulator for closed-loop control of a respective rectifier, or transmitting to an inverter regulator for closed-loop control of a respectively associated inverter; with each rectifier regulator and each inverter regulator respectively forming a difference between a predetermined nominal DC voltage and the respectively received measurement DC voltage, for producing a difference DC voltage and, furthermore, forming a difference between a nominal direct current and the respectively received measurement direct current, for producing a difference direct current, wherein the measurement direct current, the measurement DC voltage, the nominal direct current, and the nominal DC voltage are in a normalized form; each rectifier regulator controlling the respectively associated converter such that the sum of the product of the difference DC voltage and the magnitude of the nominal direct current, which is provided at the respectively associated rectifier, and the difference direct current is a minimum; and each inverter regulator controlling the respectively associated converter such that the sum of the difference DC voltage and the difference direct current is a minimum.