# US 8,786,222 B2 · Open-loop or closed-loop control method for a converter

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,786,222 B2
- Document ID: US8786222B2
- Status: Granted
- Kind: B2
- Application number: 12/995,053
- Filed: 2009-05-11
- Published: 2011-03-24
- Granted: 2014-07-22
- Earliest claimed: 2008-05-27
- Assignees: Sew-Eurodrive GmbH & Co. KG
- Applicants: Harald Wolf; Wolfgang Hammel
- Inventors: Harald Wolf; Wolfgang Hammel
- Web page: https://patentgrep.com/patent/US8786222B2

## CPC

- H02P 21/14: Estimation or adaptation of machine parameters, e.g. flux, current or voltage
- H02P 21/06: Rotor flux based control involving the use of rotor position or rotor speed sensors
- H02P 21/08: Indirect field-oriented control; Rotor flux feed-forward control
- H02P 21/26: Rotor flux based control
- H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS

## Abstract

An open-loop or closed-loop control method for a converter which supplies an electric motor, wherein a current space vector is acquired as motor current, and the motor voltage, in particular a voltage space vector, is set, an induced voltage space vector UI is determined, which is forwarded to an integration element, a flux space vector being generated, whose angular position is perpendicular to the voltage space vector, the amount of the flux space vector corresponding to a predefined nominal value, the difference of the integration result and the flux space vector thus produced being used as feedback in the integration element.

## Claims

### Claim 1

An open-loop or closed-loop control method for a converter which supplies an electric motor, comprising:
acquiring a current space vector as a motor current;
setting at least one of (a) a motor voltage and (b) a voltage space vector;
determining an induced voltage space vector;
forwarding the induced voltage space vector to an integration element;
generating a flux space vector having an angular position perpendicular to the voltage space vector, an amount of the flux space vector corresponding to a predefined nominal value; and
using a difference of an integration result and the flux space vector generated as feedback in the integration element;
wherein the integrand encompasses
U
_
I
=
U
_
S
-
R
S
·
I
_
S
-
L
S
·
ⅆ
I
_
S
ⅆ
t
;
wherein:
UI is an induced voltage space vector;
US-RS is a voltage drop at a stator winding; and
IS-LS is a flux component caused b stator current.

### Claim 2 (depends on 1)

The method according to claim 1, wherein with vanishing drift of the integration result, a feedback quantity vanishes.

### Claim 3 (depends on 1)

The method according to claim 1, wherein the difference of the integration result and the flux space vector generated is multiplied by a factor and one of (a) added to and (b) subtracted from an integrand of the integration element.

### Claim 4 (depends on 1)

The method according to claim 1, wherein the amount of the flux space vector is selected as at least one of (a) a nominal value of flux applying to the motor and (b) a nominal value of flux being generated by a magnetization produced by permanent magnets provided on a rotor in an electric motor as an synchronous motor, and corresponding to a magnetized value of the flux in the electric motor as the asynchronous motor.

### Claim 5 (depends on 1)

The method according to claim 1, wherein the angular position of the generated flux space vector is selected as a function of at least one of (a) a direction of rotation, leading or reactive to the angular position of the integrand and (b) a direction of rotation, +90° or −90° with respect to the angular position of the integrand.

### Claim 6 (depends on 1)

The method according to claim 1, wherein the space vectors lie in a plane having a normal aligned in an axial direction.

### Claim 7 (depends on 4)

The method according to claim 4, wherein the nominal value of the flux is selected to correspond to a flux specification used in regulation of the converter.