US 10,340,776 B2 · Acceleration method for V/F controlled induction motor in flux-weakening region

Abstract

The present invention provides an acceleration method for V/f controlled induction motor in flux-weakening region, which comprises: acquiring no-load magnetizing current Im of the induction motor at current stator frequency; selecting a smaller one of 0.5·Im(1/σ+1) and (Im2+σ)/(Im+σIm) as magnetizing current set point, in which σ is an estimated total leakage inductance coefficient; getting an error signal by subtracting the magnetizing current of the induction motor from the magnetizing current set point; determining the stator frequency for the next control period according to the error signal which is provided as a controlling variable of negative feedback. The acceleration method of the present invention can provide the maximum output torque in flux-weakening region and has a larger tolerance for the error of the estimated leakage inductance.

Claims15

Dependent claims

An acceleration method for a V/f controlled induction motor in a flux-weakening region comprising:

acquiring a no-load magnetizing current Im of the V/f controlled induction motor at a current stator frequency;
selecting a smaller one of 0.5·Im(1/σ+1) and (Im2+σ)/(Im+σIm) as a magnetizing current set point, in which σ is an estimated total leakage inductance coefficient;
acquiring an error signal by subtracting a magnetizing current of the V/f controlled induction motor from the magnetizing current set point, wherein the error signal is provided as a controlling variable of negative feedback;
and
determining a stator frequency for a next control period according to the error signal.

2 more elements

An acceleration system for a V/f controlled induction motor in a flux-weakening region comprising:

a no-load magnetizing current acquiring device for acquiring a no-load magnetizing current Im of the V/f controlled induction motor at a current stator frequency;
a magnetizing current setting device for selecting a smaller one of 0.5·Im(1/σ+1) and (Im2+σ)/(Im+σIm) as a magnetizing current set point, in which σ is an estimated total leakage inductance coefficient;
an error signal calculating device for acquiring an error signal by subtracting a magnetizing current of the V/f controlled induction motor from the magnetizing current set point, wherein the error signal is provided as a controlling variable of negative feedback;
and
a stator frequency determining device for determining a stator frequency for a next control period according to the error signal.

2 more elements

Dependencies are inferred from the claim text.

Acceleration method for V/F controlled induction motor in flux-weakening region

Life of this patent

Acceleration method for V/F controlled induction motor in flux-weakening region

Life of this patent

Abstract

Claims15