Patent ID: 7768805

Claim:
An active rectifier control system that is configured to enhance the response control performance for an uninterruptible power supply (UPS) system for servicing a load, the active rectifier control system providing rigid control of a direct current (dc) link voltage resulting from the combined linked outputs of a battery and the active rectifier, thus reducing the power drawn from the battery, the control system comprising: a feed-forward voltage controller, the feed-forward voltage controller comprising: a proportional-integral (PI) controller component, the PI controller component being configured to determine a voltage error reference current value in response to a dc voltage reference and a dc voltage input values; a feed-forward current determining component, the feed-forward current determining component being configured to determine a feed-forward current value in response to an active current input value, wherein the active current input value is a value determined by a function of active power required by the load and the dc link voltage, and the feed-forward current value is determined from a summation of current outputs of separate functions' separate function of the active current input value; a variable limitation component, the variable limitation component being configured to determine a limited reference current value in response to a dc reference input value; and a current control component, the current control component being configured to receive the determined limited reference current value from the variable limitation component, wherein the determined limited reference current value is utilized as a reference value for a lower level current controller.