US 6,982,534 B2
Method for operating an electronically commutated motor, and motor for carrying out one such method
Alexander Hahn, Sauldorf-Boll (Germany); Walter Heydrich, Georgen (Germany); and Hermann Rappenecker, Vöhrenbach (Germany)
Assigned to ebm-papst St. Georgen GmbH & Co. KG, St. Gerogen (Germany)
Appl. No. 10/487,461
PCT Filed Aug. 07, 2002, PCT No. PCT/EP02/08802
§ 371(c)(1), (2), (4) Date Feb. 19, 2004,
PCT Pub. No. WO03/034581, PCT Pub. Date Apr. 24, 2003.
Claims priority of application No. 101 49 935 (DE), filed on Oct. 10, 2001.
Prior Publication US 2004/0251863 A1, Dec. 16, 2004
Int. Cl. H02K 17/32 (2006.01)
U.S. Cl. 318—434 17 Claims
OG exemplary drawing
 
1. A method for operating an electronically commutated DC motor that is equipped with
a current limiting arrangement which acts on
a PWM controller that, in operation, delivers PWM pulses (60) having a controllable pulse duty ratio (pwm) and a substantially constant frequency, which current limiting arrangement, in the event a predetermined upper limit value (Isoll) of the motor current is exceeded, effects a change in the pulse duty factor, of the pulses (60) delivered by that PWM controller in order to reduce the motor current,
comprising the steps of:
monitoring whether the motor current (Iist) exceeds the predetermined upper limit value (Isoll) of the current limiting arrangement;
if the motor current (Iist) exceeds the predetermined upper limit value (Isoll) while the motor (10) is rotating, raising that limit value during a predetermined time span (T1) in order to make more motor power available during that time span.