Space vector pulse width modulation method used for three-phase inverter

Abstract

The invention discloses a space vector pulse width modulation method used for a three-phase inverter. The space vector pulse width modulation method used for the three-phase inverter comprises the following steps: A) determining a sector where a set space voltage vector locates; B) determining two nonzero basic space vectors in the sector and determining two basic space vectors with the same amplitudes and opposite directions; C) determining action time of the two nonzero basic space vectors and the two basic space vectors with the same amplitudes and opposite directions in one switch period; and D) carrying out linear combination on the two nonzero basic space vectors and the two basic space vectors with the same amplitudes and opposite directions to from the set space voltage vector. With the technical scheme of the invention, since the generation mode of zero vector is thoroughly changed, common-mode interference can be reduced from the source of the common-mode interference, and common-mode voltage is reduced; and compared with the method for filtering EMI noise by utilizing an EMI filter, the cost is greatly reduced.

Description

technical field [0001] The invention relates to the field of power electronics, in particular to a space vector pulse width modulation method for a three-phase inverter. Background technique [0002] With the development of power electronics technology, Space Vector Pulse Width Modulation (SVPWM) inverter technology has been widely used, such as frequency converter, uninterruptible power supply (UPS), photovoltaic inverter, etc. In the circuit structure of the three-phase inverter, the conventional SVPWM control method cannot effectively offset the dv / dt generated by the inverter, which will generate a jumping common-mode voltage at the midpoint of the three-phase. The specific analysis is as follows: [0003] like figure 1 In the three-phase inverter circuit shown, since the three-phase bridge arm of the inverter has 6 switching tubes in total, in order to study the space voltage vector output by the inverter when the upper and lower bridge arms of each phase have differen...

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Problems solved by technology

[0015] The technical problem to be solved by the present invention is to provide a space vector pulse width modulation method for three-phase inverters, which can reduce common-mode interference The source of common mode interference is reduced, and the cost is low

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