Patent · US Active

Method for diagnosing a frequency converter

US9431936B2 · kind B2 · utility

0Cited by

3References

5Claims

0Family size

Assignee

DR. JOHANNES HEIDENHAIN GMBH · DE

Inventors

Franz Ritz · Penzberg, DE
Norbert Huber · Erlangen, DE

Key dates

Filing date	Jan 14, 2015
Grant date	Aug 30, 2016
Priority date	—
Expiry date	Jan 18, 2035

Classification

Technology area (CPC H)Electricity
CPC primaryH02M7/48
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A method for diagnosing a frequency converter is used for a frequency converter having a positive and negative DC link voltage which is applied via bridges of switching elements in an alternating sequence to phases of a motor. Pulse width modulation (PWM) signals drive the switching elements for a respective one of the phases and current sensors capture phase currents. In a step a), PWM signals are applied as test patterns to the switching elements. In a step b), sensor signals of the current current sensors are picked up. In a step c), the sensor signals are evaluated by ascertaining a presence of the DC link voltage upon a displacement current being recognized in the sensor signals.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.