Filter network for motor control systems
AssigneeSchaffner EMV AG
InventorsMika Sippola, Peter Kull-Bucher
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Abstract
Filter network for the reduction of the voltage switching speed between an electrical motor drive and an electrical motor and/or between an electrical distribution network and a motor drive, comprising for each electrical phase a self-damped inductor having a complex impedance determined by a magnitude (Z) and a phase (φ), the phase (φ) of the complex impedance being comprised between 80 and 90 degrees in the frequency range of the motor's current, and being less than 60 degrees in the frequency range of the overvoltage oscillations. Using the inventive filter network, it is possible to manufacture low cost and small size du/dt-filters generating low voltage overshoot and low losses.
Claims20
A filter network for the reduction of voltage switching speed and of overvoltage oscillations between an electrical motor drive and an electrical motor and/or between an electrical distribution network and a motor drive, comprising for each electrical phase a self-damped inductor having a complex impedance determined by a magnitude and a phase, wherein the behavior of said self-damped inductor is such that the difference between the highest value of said phase of said complex impedance in a frequency range of the overvoltage oscillations and a lowest value of said phase of said complex impedance in said frequency range of the overvoltage oscillations is smaller than 10 degrees.
An electrical system comprising a motor drive, a filter network for the reduction of voltage switching speed and of overvoltage oscillations between an electrical motor drive and an electrical motor and/or between an electrical distribution network and a motor drive, comprising for each electrical phase a self-damped inductor having a complex impedance determined by a magnitude and a phase, wherein the behavior of said self-damped inductor is such that the difference between the highest value of said phase of said complex impedance in a frequency range of the overvoltage oscillations and a lowest value of said phase of said complex impedance in said frequency range of the overvoltage oscillations is smaller than 10 degrees, at least one cable and a motor.
Dependencies are inferred from the claim text.