A control device and a method for controlling an electric drive
AssigneeLappeenrannan-Lahden Teknillinen Yliopisto Lut
InventorRafal Piotr JASTRZEBSKI
Life of this patent
Estimating the term…
Abstract
An electric drive comprises a bearingless electric machine, a converter, and a control device. The stator of the electric machine has a cage winding including bars connected to a conductor ring. The control device controls the converter to supply torque generating current components to the bars so that torque is generated in accordance with electric machine control and to supply levitation current components to the bars so that the rotor of the bearingless electric machine is levitated in accordance with levitation control. The cage winding allows the currents of the bars to be controlled so that different current sheet distributions can be generated so as to generate desired torque and magnetic force.
Claims21
A control device for controlling an electric drive that comprises:
- an electric machine comprising a rotor and a stator, the stator comprising a cage winding comprising bars and a conductor ring electrically connecting the bars to each other, and
- a converter comprising terminals connected to first ends of the bars of the cage winding, the converter being configured to supply currents to the bars of the cage winding,
- the control device comprising a computing system configured to control the converter to:
- supply torque generating current components to the bars of the cage winding so that torque is generated in accordance with electric machine control, and
- supply levitation current components to the bars of the cage winding on the basis of a deviation of a position of the rotor from a reference position so as to control magnetic force directed to the rotor.
An electric drive comprising:
- a first electric machine comprising a rotor and a stator, the stator comprising a cage winding comprising bars and a conductor ring electrically connecting the bars to each other,
- a first converter comprising first terminals connected to first ends of the bars of the cage winding, the first converter being configured to supply first currents to the bars of the cage winding, and
- a first control device for controlling the first converter,
- wherein the first control device comprises a computing system configured to control the first converter to:
- supply torque generating current components of the first currents to the bars of the cage winding so that torque is generated in accordance with electric machine control, and
- supply levitation current components of the first currents to the bars of the cage winding on the basis of a deviation of a position of the rotor from a reference position so as to control magnetic force directed to the rotor.
A method for controlling an electric drive that comprises:
- an electric machine comprising a rotor and a stator, the stator comprising a cage winding comprising bars and a conductor ring electrically connecting the bars to each other, and
- a converter comprising terminals connected to first ends of the bars of the cage winding, the converter being configured to supply currents to the bars of the cage winding,
- the method comprising:
- controlling the converter to supply torque generating current components to the bars of the cage winding so that torque is generated in accordance with electric machine control, and
- controlling the converter to supply levitation current components to the bars of the cage winding on the basis of a deviation of a position of the rotor from a reference position so as to control magnetic force directed to the rotor.
A non-transitory computer readable medium encoded with a computer program for controlling an electric drive that comprises:
- an electric machine comprising a rotor and a stator, the stator comprising a cage winding comprising bars and a conductor ring electrically connecting the bars to each other, and
- a converter comprising terminals connected to first ends of the bars of the cage winding, the converter being configured to supply currents to the bars of the cage winding,
- the computer program comprising computer executable instructions for controlling a programmable processing system of the electric drive to control the converter to:
- supply torque generating current components to the bars of the cage winding so that torque is generated in accordance with electric machine control, and
- supply levitation current components to the bars of the cage winding on the basis of a deviation of a position of the rotor from a reference position so as to control magnetic force directed to the rotor.
(canceled)
Dependencies are inferred from the claim text.