Provided is a control circuit of a converter, in particular a power converter of a wind power installation, configured to control the converter in such a way that the converter emulates a behavior of a synchronous machine. The control circuit includes a power module for calculating a power change depending on a detected power and a correction module for setting a power set point, in particular for the converter, depending on the calculated power change.

A method for controlling a chain-link power converter including three phase legs, each of which phase legs includes a plurality of series-connected converter cells, each of the cells including a DC capacitor, the phase legs being connected in a delta configuration. The method includes detecting an unsymmetrical voltage condition at a terminal of the converter; determining a ratio between a zero sequence and a negative sequence component of a compound current to be injected into the converter, based on the detected unsymmetrical voltage condition; calculating the compound current comprising the zero sequence component and the negative sequence component in accordance with the determined ratio; and injecting the compound current into the converter to control the converter in view of the detected unsymmetrical voltage condition.

Provided is a control circuit of a converter, in particular a power converter of a wind power installation, configured to control the converter in such a way that the converter emulates a behavior of a synchronous machine. The control circuit includes a power module for calculating a power change depending on a detected power and a correction module for setting a power set point, in particular for the converter, depending on the calculated power change.

A servomotor controller includes a first and a second converter circuit that perform conversion between AC power of a power supply and DC power, a first inverter circuit that performs conversion between the DC power on the DC side of the first converter circuit and AC power on the side of a first motor, a second inverter circuit that performs conversion between the DC power on the DC side of the second converter circuit and AC power on the side of a second motor, and a power calculation unit that calculates an amount of power of the first motor, wherein control is performed so that the regenerative power of the first motor is supplied to the second motor through the power supply or the regenerative power of the second motor is supplied to the first motor through the power supply, on the basis of the amount of power.

The system has a converter for converting an AC current into a DC current, an inverter for inverting the DC power supplied from the converter into an AC power, a servo control device for controlling a drive of a servo motor, and a resistance regenerating circuit for consuming a regenerative energy. The servo control device has a plurality of motor control portions for enabling a plurality of servo motors to be controlled and a plurality of control port portions corresponding to a plurality of motor control portions. At least one of the plurality of motor control portions is configured so that a power supply regenerating control function portion and a control function portion for the servo motor can be switched. The robot control system capable of suppressing the increase of the development cost and adding the power supply regenerating function can be provided.

A servomotor controller includes a first and a second converter circuit that perform conversion between AC power of a power supply and DC power, a first inverter circuit that performs conversion between the DC power on the DC side of the first converter circuit and AC power on the side of a first motor, a second inverter circuit that performs conversion between the DC power on the DC side of the second converter circuit and AC power on the side of a second motor, and a power calculation unit that calculates an amount of power of the first motor, wherein control is performed so that the regenerative power of the first motor is supplied to the second motor through the power supply or the regenerative power of the second motor is supplied to the first motor through the power supply, on the basis of the amount of power.