Rockwell Automation Technologies Incorporated

Todd M Oestreich

Gary Leonard Skibinski

Zoran Vrankovic

Gerry M Nagel

Gennadi Sizov

David A Figie

Adam M Shea

Yao Da

Robert H Schmidt

Michael S Baran

Craig R Winterhalter

Murray E Hersh

Timothy A Davis

A motor drive that outputs a sinusoidal waveform utilizes power switching devices operable at high switching frequencies. The switching devices may be operated, for example, between twenty kilohertz and one megahertz. A first filter is included at the output of the motor drive which has a bandwidth selected to attenuate voltage components at the output which are at the switching frequency or multiples thereof such that the output voltage waveform is generally sinusoidal. Additional filtering is included within the motor drive to establish a circulation path for common mode currents within the motor drive. Further, a shield is provided adjacent to those components within the motor drive that may experience voltage or current waveforms at the switching frequency or multiples thereof to cause radiated emissions to establish eddy currents within the EMI shield rather than passing through the shield into the environment.

System and method for sinusoidal output and integrated EMC filtering in a motor drive

A motor controller executing a current regulator and a modulation routine in separate update intervals provides an improved fundamental voltage waveform for a motor controlled by the motor controller. The current regulator is executed at a first periodic update rate and the modulation routine is executed at a second periodic update rate, where the frequency at which the modulation routine executes is at least twice the frequency at which the current regulator executes. Executing the current regulator and the modulation routines at different frequencies results in the current regulator generating a single voltage reference signal for multiple periods of the modulation routine. To reduce voltage ripple induced by decoupling execution of the current regulator and the modulation routine, the motor controller extrapolates the voltage reference generated by the current regulator into multiple voltage reference signals, where a unique voltage reference signal is provided for each period of the modulation routine.

Voltage rotator for high switching frequency PWM inverter

A method for controlling voltage of a DC bus in a converter circuit is provided. The method includes monitoring a duty cycle of a switch that connects a resistive circuit across the DC bus, the switch being closed when the DC bus voltage reaches an upper voltage value and opened when the DC bus voltage reaches a lower voltage value and altering the lower voltage value based upon the duty cycle of the switch.

Converter circuit with adjustable DC bus voltage

An automation network that utilizes motor drives to diagnose faults, and provide potential solutions to a user. The fault status and/or diagnostic remedies may be displayed via a user display integrated with (e.g., in a single cabinet with) the motor drives and/or coupled to (e.g., in an external device separate from) the motor drives. As such, a logic process or other algorithm may be executed by the motor drive to determine a potential set of solutions for any given fault, based on, for example, determined errors and likelihood of causes for presentation to a user. In this manner, motor drives may allow for user corrective actions to be communicated to a user.

Error diagnostics and prognostics in motor drives

DC bus voltage control method and system

A method for controlling a motor drive system, the system comprising an AC-DC converter coupled to a DC-AC inverter by a DC bus, a motor coupled to and driven by the inverter, and a load coupled to and driven by the motor is provided. The method includes accessing a motion profile for the motor and load and determining power losses of the converter, the inverter, the motor and the load. The method also includes controlling the voltage of the DC bus based upon the motion profile and the power losses to enhance the motor drive system efficiency, reliability and motor shaft performance.

Motor drive system with bus voltage control

A system and method in accordance with the present technique for protecting motor drives from damage due to misconfiguration while coupled to a common DC bus, comprises sensing electrical operating parameters of the motor drives, automatically determining whether each of the drives is actually installed as a common bus leader or a common bus follower, and comparing the actual installation of the motor drives to a respective stored configuration of each of the motor drives as either a common bus leader or a common bus follower.

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Cedarburg, WI, United States of America

Todd M Oestreich