Method for controlling the electromagnetic torque of a high-speed-synchronous machine

Patent metadata

Field	Value
Publication number	US-9455660-B2
Application number	US-201314404515-A
Country	US
Kind code	B2
Filing date	May 16, 2013
Priority date	May 29, 2012
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A method for controlling electromagnetic torque of a three-phase synchronous machine with permanent magnets, including measuring current delivered to the three phases of the machine, transposing the three measured currents into a direct current component and a quadratic current component using Park's transformation, and receiving an instruction for the quadratic current component. When the direct current component is negative, a defluxing control mode is activated in which the machine is controlled from a direct voltage component and a quadratic voltage component of the machine, the direct voltage component and the quadratic voltage component being determined in Park's plane.

First claim

The invention claimed is:

1. A method for controlling electromagnetic torque of a three-phase synchronous machine with permanent magnets, the method comprising:
measuring current delivered to the three phases of the machine;
transposing the three measured currents into a direct current component and a quadrature current component on the basis of a transform of the three-phase systems;
receiving a setpoint for the quadrature current component; and
when the direct current component is negative, activating a defluxing control mode in which the machine is controlled on the basis of a direct voltage component and a quadrature voltage component of the machine, the direct voltage component and the quadrature voltage component being determined in the plane related to the transform of the three-phase systems;
wherein the direct component and the quadrature component of the control voltage of the synchronous machine depend on a same control parameter, determined to maintain a value of the direct current component near to zero and enabling a term due to magnetic flux of the permanent magnets to be compensated, and
wherein the defluxing control mode is exited when the direct current component returns to a positive or zero value.

2. The method as claimed in claim 1 , wherein the synchronous machine has perfect symmetry between the direct axis and the quadrature axis of the plane of the transform of the three-phase systems, enabling equality to be obtained between equivalent inductances on each axis of the plane of the transform of the three-phase systems.

3. The method as claimed in claim 1 , wherein the direct component and the quadrature component of the control voltage are preferably proportional to a same maximum amplitude, and depend in a sinusoidal manner on the control parameter, the control parameter varying within a range

[

-

π
2

;

π
2

]

.

4. The method as claimed in claim 3 , wherein the direct component and the quadrature component are expressed according to expression:

{

V
d

=

-

V
bat

3

⁢

sin
⁡

(
θ
)

V
q

=

V
bat

3

⁢

cos
⁡

(
θ
)

.

5. The method as claimed in claim 1 , wherein the transform of the three-phase systems is a Park transform.

6. A system for controlling electromagnetic torque of a three-phase synchronous machine with permanent magnets, the system comprising:
means for measuring current delivered to the three phases of the machine;
means for transposing the three measured currents into a direct current component and a quadrature current component on the basis of a transform of the three-phase systems;
means for receiving a setpoint for the quadrature current component; and
control means for activating, when the direct current component is negative, a defluxing control mode in which the machine is controlled on the basis of a direct voltage component and a quadrature voltage component of the machine, the direct voltage component and the quadrature voltage component being determined in the plane related to the transform of the three-phase systems,
wherein the control means comprises a proportional-integral controller configured to determine a same control parameter whose direct voltage component and quadrature voltage component depend on the difference between the setpoint for the quadrature current component and the value of the quadrature current component, and a module configured to determine the direct and quadrature voltage components on the basis of the control parameter.

7. The system as claimed in claim 6 , wherein the control means comprises an activation module configured to activate the defluxing control mode when the direct current component is negative, and to disable the defluxing control mode when the direct current component is positive.

8. The system as claimed in claim 6 , further comprising transposition means configured to apply a Park transform to the measured currents to obtain the direct current component and the quadrature current component.

9. A method for controlling electromagnetic torque of a three-phase synchronous machine with permanent magnets, the method comprising:
measuring current delivered to the three phases of the machine;
transposing the three measured currents into a direct current component and a quadrature current component on the basis of a transform of the three-phase systems;
receiving a setpoint for the quadrature current component; and
when the direct current component is negative, activating a defluxing control mode in which the machine is controlled on the basis of a direct voltage component and a quadrature voltage component of the machine, the direct voltage component and the quadrature voltage component being determined in the plane related to the transform of the three-phase systems;
wherein the direct component and the quadrature component of the control voltage of the synchronous machine depend on a same control parameter, determined to maintain a value of the direct current component near to zero and enabling a term due to magnetic flux of the permanent magnets to be compensated, and
wherein the synchronous machine has perfect symmetry between the direct axis and the quadrature axis of the plane of the transform of the three-phase systems, enabling equality to be obtained between equiva

Assignees

• Renault Sa

Inventors

• Merienne Ludovic
• Maloum Adbelmalek

Classifications

• H02P21/141 Primary

  Flux estimation · CPC title

• H02P21/0089 Primary

  using field weakening · CPC title

• H02P21/08

  Indirect field-oriented control; Rotor flux feed-forward control · CPC title

• H02P21/00 Primary

  Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation · CPC title

• H02P21/12

  Stator flux based control involving the use of rotor position or rotor speed sensors · CPC title