Induction motor and controller device therefor
AssigneeHiroyuki Nashiki
InventorsMasayuki Nashiki, Hiroyuki Nashiki
Life of this patent
Estimating the term…
Abstract
In induction motors, efficiency is improved and a maximum torque is increased. For a magnetic flux density of the stator pole for each phase of an induction motor, a circumferential magnetic flux density distribution is controlled to any distribution state, from a trapezoidal wave-like distribution close to a square wave to a sinusoidal distribution. In particular, motor efficiency in a range of low to medium rotations is improved. The motor structure is designed to reduce the leakage inductance of the rotor windings, and the motor and control thereof are optimized for each other. This increases the maximum torque of the motor more effectively. In addition, the high efficiency of the motor makes it possible to reduce the size of the drive circuit.
Claims20
An induction motor and control device thereof, comprising:
- stator windings SW1, SW2, SW, . . . , SW(N1) arranged for each of phases within an electrical angle of 360 degrees in a circumferential direction of a stator;
- magnetic sections G1, MG2, MG3 . . . MG(N2) which are circumferential sections located close to an air gap between the stator and a rotor, which are located within an electrical range of 360 degrees, and which shows stator teeth each arranged between the stator windings of each of the phases or circumferential widths corresponding to the stator tooth;
- a plurality of rotor windings RW arranged closely on a surface of a rotor in the rotor, induced currents flowing due to magnetic excitation in the stator;
- a drive circuit DTR which drives voltage and current of the phases supplied to the respective stator windings;
- and
- a motor control means MCM which obtains values including current command values, and drives the stator windings with the drive circuit DTR,
- wherein
- the control is performed in a state in which a field flux φm near the air gap for each of the magnetic sections, an electromotive force to excite a magnetic flux density of the field flux φm, or excitation current components for excitation including a field magnetic flux excitation are given as individual values for each of the magnetic sections, and
- a rotor current component superposed to each of the stator windings is supplied to the rotor windings of the rotor,
- wherein the number N1 is an integer greater than or equal to 6 and the number N2 is an integer greater than or equal to 6.
Dependencies are inferred from the claim text.