Title: Pulse width modulation method
Application Number: 200610163053 Application Date: 2006.12.01
Publication Number: 1976195 Publication Date: 2007.06.06
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: H02M7/48;H02P27/02
Applicant(s) Name: Heidenhain GmbH Dr. Johannes Address:
Inventor(s) Name: Huber Norbert;Ritz Franz;Lengenfelder Hans
Attorney & Agent: liuchun yuan wangzhong zhong
Abstract:
    A method is describes for the pulse width modified control of switching elements in a frequency converter having N phases, in which for each phase the control pulses of the switching elements are derived from, in each case, one P-periodic control voltage. The P-periodic control voltages correspond to a superposition of sinusoidal control voltages of period P, that are shifted by 360/N degrees with respect to one another, by an N*P-periodic offset voltage that applies to all phases. The offset voltage is selected such that, at any time, exactly one of the P-periodic control voltages lies effectively on a modulating limit for the derivation of the switching pulses. Using this method, the excitation of resonances at the star point of a connected load may be clearly reduced.
Time: 5
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