Patent
Pwm inverter device
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TLDR
In this article, a PWM inverter with PWM pulse output is used for comparing a phase voltage instruction with a triangular carrier wave and outputting a pWM pulse signal.Abstract:
When switching from a sinusoidal wave voltage output to a 6-stp voltage output, it is difficult to obtain a smooth mode switching and a complicated switching processing is required. This problem is solved by a PWM inverter device having PWM pulse output means (2) for comparing a phase voltage instruction with a triangular carrier wave and outputting a PWM pulse signal, the device further including voltage instruction processing means (1) operating in such a manner that among phase voltage instructions, a phase having the maximum absolute value is selected and if this phase voltage instruction is greater than the maximum value of the carrier wave, the phase voltage instruction subtracted by the maximum value of the carrier wave is subtracted from each phase voltage instruction and if this phase voltage instruction is smaller than the minimum value of the carrier wave, the phase voltage instruction subtracted by the minimum value of the carrier wave is subtracted from each phase voltage instruction, so that the value obtained by the subtraction is used as each phase output voltage instruction, and in the other cases, the phase voltage instruction is used directly as the phase output voltage instruction for output to the PWM pulse output means (2).read more
Citations
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References
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Patent
Capacitor charge balancing technique for a three-level PWM power converter
TL;DR: In this article, an imbalance compensation coefficient is derived from the difference in voltages across the first and second capacitors and from the direction of current between the neutral node and the inverter.
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Tokunosuke Tanamachi,Kiyoshi Nakamura,Kiyoshi Nakata,Yoshio Tsutsui,Wataru Miyake,Katsuaki Suzuki +5 more
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Patent
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Vladimir Blasko,Vikram Kaura +1 more
TL;DR: In this paper, a method and/or apparatus for converting voltage using a pulse width modulator and an inverter/converter, including three legs and a triangle signal generator, is described.