Control arrangement for a uniform load distribution of at least two power supply devices connected in parallel at the output side

摘要

A control arrangement for the uniform load distribution of at least two power supply devices connected in parallel at their outputs and designed as switch controllers having pulse width modulators provides a common voltage regulator for the power supply devices and a respective non-steady and a steady current regulator per power supply device. The control outputs of three respective regulators are connectred to maximum value selection circuits which precede the pulse width modulators. In three-phase operation having a center conductor of such devices, a uniform load distribution to each device and, therefore, a balancing of the three-phase network is achieved by substituting a proportional-integral controller for the non-steady current regulators and forming the difference of the output currents of the switch controllers with the proportional-integral controller so that the controlling variable at the output thereof is supplied to one maximum value selection circuit via an inverter and is directly supplied to the other maximum value selection circuit.