Decive and method for network-side intermediate voltage regulation

The present invention discloses a device and a method for mains-side control of an intermediate circuit voltage in order to reduce or eliminate impermissible mains effects of harmonics of the mains voltage on the intermediate circuit. For this purpose, during the control of the intermediate circuit voltage, the mains-side supplied power is adapted to the motor-side delivered power. The device according to the invention comprises, among other things, an intermediate circuit voltage controller (1) for determining a power requirement, a calculation device (2) for calculating an inverter target voltage phasor and a mains current setpoint value phasor, a transformation device (3) for transforming these phasors into the time domain, a mains current control device (4), a controlled system device (5) for determining and controlling a mains voltage fundamental frequency phasor and a mains frequency, a device for mains voltage feed-on as well as a dynamic filter device. The mains current control device (4) controls a DC component in the mains current by compensating it through suitable filtering. The device for mains voltage feed-on relieves the mains current control device (4) in the case of mains voltage harmonics by feeding mains voltage harmonics onto the inverter total voltage. The dynamic filter device is located at the input of the device for mains-side control of an intermediate circuit voltage, filters even harmonics of the fundamental frequency from the intermediate circuit voltage and then subtracts them from the actual value of the intermediate circuit voltage.