Motor drive architecture with active snubber
AssigneesPratt & Whitney Canada Corp., Hamilton Sundstrand Corporation
InventorsKevin A. Dooley, Gregory I. Rozman
Life of this patent
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Abstract
A method and apparatus is disclosed for controlling a system comprising at least one electric motor. The motor drive circuit includes a reconfigurable active snubber. Under given resonance conditions, the active snubber is configured to use a resistive element to dissipate electrical transients across the commutation circuit.
Claims14
An active electrical protection apparatus for damping electrical transients in a control circuit of an electrical machine having phase windings driven using a commutation circuit and powered through a power supply line, the apparatus comprising:
- a power dissipating circuit arranged in parallel with said commutation circuit and configured to dissipate power on the power supply line, the power dissipating circuit having a resistive element and a first switch configured to switchably connect said resistive element to the power supply line;
- a resonance detector configured to evaluate a frequency of a current on the power supply line, detect a resonance condition on said power supply line based on the evaluated frequency and provide a resonance signal representative of the resonance condition;
- and
- a controller configured to receive the resonance signal and command said first switch at least as a function of said resonance signal.
An active electrical protection apparatus for damping electrical transients in an electrical machine having phase windings driven using a commutation circuit and powered through a power supply connecting line, the apparatus comprising:
- a power dissipating device arranged in parallel with said commutation circuit, and having a resistive element configured to dissipate power on the power supply connecting line when the electrical transients on the power supply connecting line are damped;
- a transient suppression device arranged in series with said power dissipating circuit and with said commutation circuit, and having a feedback diode device arranged inversely relative to a drive current of said commutation circuit;
- a switching device configured to switchably connect said power dissipating device to the power supply connecting line and to switchably connect said transient suppression device;
- a resonance detector configured to evaluate a frequency of a current on the power supply line, detect a resonance condition on said power supply line based on the evaluated frequency and provide a resonance signal representative of the resonance condition;
- and
- a switch controller configured to receive the resonance signal and command said switching device at least as a function of said resonance signal.
A method for damping electrical transients in an electrical machine having phase windings driven using a commutation circuit, the machine further having a resistive element arranged in parallel with said commutation circuit wherein the resistive element is configured to dissipate power when electrical transients are damped and a feedback diode device arranged in series with said power dissipating circuit and with said commutation circuit, and arranged inversely relative to a drive current of said commutation circuit, the method comprising:
- evaluating a resonance condition based on at least one of a frequency of a current on a power supply line and an operation frequency of said electrical machine;
- switching said feedback diode device in and out as a function of said resonance condition;
- measuring a voltage across said commutation circuit;
- comparing a value of said voltage to a limit voltage value to detect a voltage transient which determines a voltage condition;
- and
- switching said resistive element in and out as a function of said resonance condition and said voltage condition.
A method for damping electrical transients in an electrical machine having phase windings driven using a commutation circuit, the electrical machine further having a resistive element arranged in parallel with said commutation circuit, the resistive element for dissipating power when electrical transients on a power supply line are damped, the method comprising:
- evaluating a frequency of a current on the power supply line of said electrical machine;
- detecting a resonance condition on said power supply line based on the evaluated frequency;
- and
- switching said resistive element in to damp electrical transients on the power supply line and out at least as a function of said electrical resonance condition.
Dependencies are inferred from the claim text.