Method and apparatus for monitoring motor rotation speed

US7075446B2 · kind B2 · utility

Assignee

• ebm-papst St. Georgen GmbH & Co. KG · DE

Inventors

• Hans-Dieter Schondelmaier · St. Georgen, DE
• Arnold Kuner · St. Georgen, DE
• Frank Jeske · Tennenbronn, DE

Key dates

• Filing date: Dec 5, 2002
• Grant date: Jul 11, 2006
• Expiry date: Jun 11, 2023

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F04D27/008
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The invention concerns a method for generating an alarm signal in a motor which comprises a rotor (50) whose actual rotation speed during operation lies in a normal zone (nSoll, TSoll), can deviate from that normal zone in the event of a fault, and is to be monitored against a malfunction or fault state, comprising the following steps: At least one alarm switch-on rotation speed (nAOn, TAOn) and at least one alarm switch-off rotation speed (nAOff, TAOff) are defined, of which the latter is located closer to the normal zone than the former, an associated pair of alarm switch-on rotation speed and alarm switch-off rotation speed defining between them a hysteresis zone. When the rotation speed to be monitored arrives, coming from the hysteresis zone, at the alarm switch-on rotation speed, an alarm switch-on criterion (Flag DIR=0) is generated. The duration of this alarm switch-on criterion is monitored. When this duration reaches a predetermined value (tdOn), an alarm signal (ALARM) is activated (FIG. 13: S186, S194). A corresponding microprocessor-controlled motor can be used to implement the method.