| 摘要 |
PROBLEM TO BE SOLVED: To suppress a current clamping phenomenon during a dead time period. SOLUTION: In the voltage-type PWM inverter device, a trapezoidal compensation voltage (dead-time compensation voltage and Vce compensation voltage) is generated by circuits 11 to 14, and it is added to a voltage command outputted from a voltage command computing element 5. In a PWM pulse computing element 6, a PWM operation based on the voltage command to which a trapezoidal compensation voltage is added is performed, dead time is added, a drive signal to the inverter 1 is generated and the inverter 1 is controlled. A switch 15 in which a PWM circuit 16 is connected to an integrator 14 outputting the trapezoidal compensation voltage, which is controlled by the output of a comparator 11 and controls the input of a triangular wave to the PWM circuit 16, is installed. When the comparator 11 outputs a voltage (period equivalent to the inclined part of the trapezoidal compensation voltage), the triangular wave is inputted to the PWM circuit 16, and the inclined part of the trapezoidal compensation voltage is put into PWM. Since the zero clamping time of voltage becomes short, since trapezoidal compensation voltage is turned into PWM, current zero clamping is suppressed. COPYRIGHT: (C)2003,JPO
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