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US 9,793,844 B2Granted
Permanent magnet motor controller
AssigneeMitsubishi Heavy Industries, Ltd.
InventorsYukio Yamashita, Noriyuki Hayashi
Life of this patent
Estimating the term…
Abstract
An object is to provide a permanent magnet motor controller capable of suppressing the rotary bending vibration that occurs in the permanent magnet motor effectively with simple configuration. A permanent magnet motor controller uses the dq coordinate conversion. A dq target current setting part adds the current component (i*da) that cancels the magnetic attractive force acting in the radial direction of the rotational shaft of the rotor of the permanent magnet motor to the d-axis target current value, whereby the eccentricity of the rotational shaft of the rotor is reduced.
Claims8
A permanent magnet motor controller including a rotor rotational shaft rotatably supported by a bearing, the permanent magnet controller comprising:
- a current detecting part configured to detect a phase current flowing through a permanent magnet motor;
- a three-phase/dq coordinate converting part configured to convert the phase current detected by the current detecting part into a current value of an orthogonal coordinate system (hereinafter, referred to as “dq coordinate system”) that rotates in synchronization with a rotation of a motor;
- a dq target current setting part configured to set a target current value of the dq coordinate system based on a rotation speed of the motor;
- a dq target voltage generating part configured to generate a target voltage value of the dq coordinate system based on the current value of the dq coordinate system converted by the three-phase/dq coordinate converting part and the target current value of the dq coordinate system set by the dq target current setting part;
- a dq/three-phase coordinate converting part configured to convert the target voltage value of the dq coordinate system generated by the dq target voltage generating part into a three-phase target voltage value;
- a power converting part configured to convert the three-phase target voltage value generated by the dq/three-phase coordinate converting part into a three-phase motor driving current;
- a rotation angle detecting part configured to detect a rotation angle of the rotor;
- and
- a table configured to define in advance a displacement in a radial direction of the rotor based on the rotation angle of the rotor rotational shaft,
- wherein a cyclic displacement having an eccentric frequency is defined in the table, the eccentric frequency being determined by a pole number of the permanent magnet motor and a slot number of the permanent magnet motor, and
- wherein the dq target current setting part is configured to estimate a displacement corresponding to a detected value of the rotation angle detecting part based on the table and add a current component which is obtained from the estimated displacement and cancels a magnetic attractive force to a d-axis target current value set in the dq target current setting part so as to reduce an eccentricity of the rotor rotational shaft, the magnetic attractive force acting in a radial direction of a rotor rotational shaft of the permanent magnet motor and having cyclic behavior every electric angle of the rotor.
8 more elements
A permanent magnet motor controller including a rotor rotational shaft rotatably supported by a bearing, the permanent magnet motor controller comprising:
- a current detecting part configured to detect a phase current flowing through a first stator winding wound around a stator iron core of a permanent magnet motor;
- a three-phase/dq coordinate converting part configured to convert the phase current detected by the current detecting part into a current value of an orthogonal coordinate system (hereinafter, referred to as “dq coordinate system”) that rotates in synchronization with a rotation of a motor;
- a dq target current setting part configured to set a target current value of the dq coordinate system based on a rotation speed of the motor;
- a dq target voltage generating part configured to generate a target voltage value of the dq coordinate system based on the current value of the dq coordinate system converted by the three-phase/dq coordinate converting part and the target current value of the dq coordinate system set by the dq target current setting part;
- a dq/three-phase coordinate converting part configured to convert the target voltage value of the dq coordinate system generated by the dq target voltage generating part into a three-phase target voltage value;
- a power converting part configured to convert the three-phase target voltage value generated by the dq/three-phase coordinate converting part into a three-phase motor driving current;
- a second stator winding wound around the stator iron core of the permanent magnet motor independently of the first stator winding;
- a rotation angle detecting part configured to detect a rotation angle of the rotor;
- and
- a table configured to define in advance a displacement in a radial direction of the rotor based on the rotation angle of the rotor rotational shaft,
- wherein a cyclic displacement having an eccentric frequency is defined in the table, the eccentric frequency being determined by a pole number of the permanent magnet motor and a slot number of the permanent magnet motor,
- wherein the displacement of the radial direction of the rotor based on the rotation angle of the rotor rotational shaft is estimated based on the table, and
- wherein a current which is obtained from the estimated displacement and cancels a magnetic attractive force is applied to the second stator winding so as to reduce an eccentricity caused on the rotor rotational shaft, the magnetic attractive force acting in a radial direction of the rotor rotational shaft of the permanent magnet motor and having cyclic behavior every electric angle of the rotor.
10 more elements
A permanent magnet motor controller comprising:
- a current detecting part configured to detect a current which flows through a magnet bearing rotatably supporting a rotor rotational shaft of a permanent magnet motor;
- a displacement sensor configured to detect a displacement amount in a radial direction of the rotor rotational shaft;
- a target current value setting part configured to set a target current value flowing through the magnet bearing based on a detected value of the displacement sensor;
- a current control part configured to control the current flowing through the magnet bearing so that the current becomes the target current value;
- a rotation angle detecting part configured to detect a rotation angle of the rotor;
- and
- a table configured to define in advance a displacement in a radial direction of the rotor based on the rotation angle of the rotor rotational shaft,
- wherein a cycle displacement having an eccentric frequency is defined in the table, the eccentric frequency being determined by a pole number of the permanent magnet motor and a slot number of the permanent magnet motor, and
- wherein the target current setting part is configured to estimate a displacement corresponding to a detected value of the rotation angle detecting part based on the table and add a current component which is obtained from the estimated displacement and cancels a magnet attractive force to the target current value so as to reduce an eccentricity of the rotor rotational shaft, the magnet attractive force acting in a radial direction of the rotor rotational shaft of the permanent magnet motor and having cyclic behavior every electric angle of the rotor.
6 more elements
Dependencies are inferred from the claim text.