Position sensorless open loop control for motor drives with output filter and transformer
AssigneeRockwell Automation Technologies, Inc.
InventorsJingbo Liu, Thomas Nondahl, Peter Schmidt, Semyon Royak
Life of this patent
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Abstract
A power converter, control apparatus and methods are presented for driving a permanent magnet motor or other load through a sine wave filter and a transformer, in which inverter output current is controlled using a current-frequency relationship to convert a desired frequency or speed value to a current setpoint, and the inverter output current is regulated to the current setpoint using a control algorithm with a bandwidth below the resonant frequency of the sine wave filter.
Claims20
A power conversion system, comprising:
- an inverter operative to provide AC output power to drive a load;
- and
- a controller operative to regulate at least one inverter output current according to a frequency or speed setpoint value via a control algorithm having a current-frequency relationship with a zero current value corresponding to a zero frequency value, and a bandwidth below a resonant frequency of a filter coupled between the inverter and the load.
A method for controlling a power conversion system driving a load through a filter, the method comprising:
- determining a current setpoint value according to a frequency or speed setpoint value;
- sampling at least one AC output current feedback signal or value of the power conversion system;
- and
- regulating the at least one AC output current according to the current setpoint value and the at least one AC output current feedback signal or value using a control algorithm having a current-frequency relationship with a zero current value corresponding to a zero frequency value, and a bandwidth below a resonant frequency of the filter.
A non-transitory computer readable medium with computer executable instructions for controlling a power conversion system driving a load through a filter, the computer readable medium comprising computer executable instructions for causing a processor when executed to:
- determine a current setpoint value according to a frequency or speed setpoint value;
- sample at least one AC output current feedback signal or value of the power conversion system;
- and
- regulate the at least one AC output current according to the current setpoint value and the at least one AC output current feedback signal or value using a control algorithm having a current-frequency relationship with a zero current value corresponding to a zero frequency value, and a bandwidth below a resonant frequency of the filter.
Dependencies are inferred from the claim text.