Aktives Tiefpassfilter für ein Pwm-Signal für den Antrieb eines Motors

Details

Veröffentlichungs-Nr.

EP4776495

Anmeldetag

13. Januar 2025

Veröffentlichung

15. Juli 2026

Rechtsraum

EP

IPC

H02M1/12, H02M1/15

Abstract

The present invention relates to a low-pass active filter (10) for a motor-driving PWM signal generated by a power inverter (30) in an electric motor drive. The active filter (10) comprises a first transformer (12) having a primary winding (L₁) and a secondary winding (L₂), a first low-pass passive filtering circuit (14) arranged to filter the output signal of said primary winding (L₁) in order to power the electric motor, a current sensor (16) for measuring a current (I_p) flowing in the active filter (10) and an amplifier (18) configured to generate and inject a compensating current (I_s) into said secondary winding (L₂). The compensating current (I_s) is the current (I_p) measured by the current sensor (16) multiplied by the gain of the amplifier (18). The primary winding (L₁) of the first transformer (12) is the inductor component of the filtering circuit (14). The gain of the amplifier (18) is determined such that said compensating current (I_s) is adapted to counteract the high-frequency PWM voltage component in the motor-driving PWM signal through the mutual inductance of said first transformer (12) in order to at least attenuate ripple in said signal.

Anmelder

Firma

ETEL S.A.

Land

🇨🇭 Schweiz

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