Phase current detection method, inverter control method, motor control method and apparatus for carrying out these methods
AssigneeDaikin Industries, Ltd.
InventorsToshiyuki Maeda, Tomoisa Taniguchi
Life of this patent
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Abstract
Apparatus and methods for phase current detection used for driving a motor by supplying outputs from a pulse width modulation (PWM) converter to the motor. One method presented provides detecting a DC link current and a vector pattern, determining whether a voltage vector lengths exceeds a predetermined value, and adjusting the voltage vector by adding a positive or reversed voltage based upon the above determination and an integrated error value.
Claims12
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current, on an input side of said inverter, and a vector pattern to be applied;
- determining whether a voltage vector length exceeds a predetermined value;
- adjusting the voltage vector by varying a pulse application interval of a voltage vector command to said PWM inverter based upon the result of said determining step, thereby adjusting multi-phase AC voltage applied to terminals of said motor to drive said motor.
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current;
- calculating a current pattern;
- determining whether current detection is possible during a dead time;
- carrying out current detection in response to said determining step determining that current detection is possible;
- and
- controlling a voltage vector command to said PWM inverter based on the result of said current detection.
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current and a vector pattern to be applied;
- determining whether a voltage vector length exceeds a predetermined threshold;
- and
- calculating an estimated current from past current values based upon the result of said determining step;
- and
- controlling a voltage vector command to said PWM inverter based on the result of said calculating step.
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current and a vector pattern to be applied;
- correcting the current detection value using a prior current estimation value;
- estimating a new current value at a desired timing using the corrected current detection value;
- and
- controlling a voltage vector command to said PWM inverter based on the result of said estimating step.
An inverter control method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current and a current command;
- and
- carrying out a current control using differences between DC link currents measured at two voltage vectors within a carrier interval and current commands corresponding to phases in which said DC link currents flow to control said PWM inverter.
An inverter control apparatus for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- a detector for detecting DC link current, and a current command;
- a position-sensorless controller which uses differences between DC link currents measured at two voltage vectors within a carrier interval and current commands corresponding to phases in which said DC link currents flow to control said PWM inverter, thereby adjusting multi-phase AC voltage applied to terminals of said motor to drive said motor.
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- estimating direction of a phase current at a current detection timing, and
- varying a minimum pulse width of a voltage vector command to said inverter based upon the estimation result.
A phase current detection method used to control a motor, comprising:
- calculating a phase current from a current of a DC link and vector pattern;
- connecting a converter for carrying out a switching operation to the PWM inverter in series;
- and
- prohibiting switching of the converter and the PWM inverter at a current detection timing.
A phase current detection method for driving a motor by supplying outputs from a PWM inverter to the motor, comprising:
- detecting a DC link current, and a vector pattern to be applied;
- determining whether a voltage vector length exceeds a predetermined value;
- enlarging said voltage vector length based upon a negative result of said determining step to output switching signal to said PWM inverter:
- and
- prohibiting outputting of said switching signal to said inverter for a constant period after output of said switching signal.
Dependencies are inferred from the claim text.