| 摘要 |
PROBLEM TO BE SOLVED: To provide an inverter which can suppress third harmonic waves caused by a switching operation and provide sinusoidel AC voltage with a little distortion. SOLUTION: NPN transistors 11-14 are on/off-controlled by control signals AP, AN, BP, BN from switching controlling circuits 15a and output AC voltages C, D of two phases which have a 120 deg. phase difference to two output lines 21, 22. A low-pass filter 16 outputs the voltage between the two output lines after eliminating high-frequency components. When the AC voltages C, D are supplied to the low-pass filter 16, third harmonic waves of the two AC voltages C, D are canceled by each other. Therefore, the same operation as in the case that basic waves of the AC voltages C, D are supplied to the low-pass filter 16 through the output lines 21, 22 can be obtained. |
