Patent Number: 6,166,929

Title: CSI based drive having active damping control

Abstract: A multi-motor drive in which the resonance existing between one or more output filter capacitors of a current source inverter and an a.c. induction motor is reduced. The inverter features a switching pattern generator which controls the power switches of the inverter based on a reference current. A control loop, connected to the switching pattern generator, measures the load current or voltage and generates a nominal reference current based on an error therein; determines a damping current based on the voltage at the terminal; and determines the reference current supplied to the switching pattern generator by subtracting the damping current from the nominal reference current. The invention essentially simulates the use of a physical damping resistor connected in parallel with each output filter capacitor, but without the corresponding energy loss. This form of active damping control is also applied to a resonance mode existing between the input filter capacitors of a PWM-based rectifier and the system inductance of a power source.

Inventors: Ma; Daming (Toronto, CA), Wu; Bin (Toronto, CA), Zargari; Navid R. (Cambridge, CA), Rizzo; Steven C. (Cambridge, CA)

Assignee: Rockwell Technologies, LLC

International Classification: H02M 5/00 (20060101); H02P 5/74 (20060101); H02M 5/45 (20060101); H02M 007/155 ()

Expiration Date: 12/26/2017