DAMPING OR RESONANT PEAKS IN AN ELECTRIC MOTOR WHICH IS OPERATED USING A CONVERTER WITH AN INTERMEDIATE VOLTAGE CIRCUIT, BY MEANS OF A TRANSFORMER-COUPLED DAMPING RESISTANCE, AND A CORRESPONDING ELECTRIC MOTOR
US6580248B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 2001 |
| Grant date | Jun 17, 2003 |
| Priority date | — |
| Expiry date | Jul 31, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/126
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a converter system having an intermediate voltage circuit which operates with a supply network-side input inductor in the step-converter mode or has other input-side inductances, there is a risk of natural system oscillations being formed via discharge capacitances in conjunction with motors. If the motor now has an amplitude/frequency response with a pronounced resonant frequency in the region of such natural system oscillations, then there is a risk of higher voltages occurring at the motor star point (S) than in the motor phases (I, V, W). This is prevented by the present invention by introducing an impedance (Z), in particular at the input to the motor, in order to damp capacitive discharge currents to ground potential, which are caused by system oscillations (fsys) (excited asymmetrically with respect to ground in the motor phases (U, V, W)) of the converter system (LK, UR, LT, M) in the winding sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.