| 摘要 |
PURPOSE:To prevent an induction defect by forming a modulation signal by comparing a triangular carrier with a triangular modulated wave when the frequency of an inverter is in the prescribed frequency range. CONSTITUTION:When the frequency of an inverter is in the prescribed frequency range(e.g., 8Hz-12Hz), a triangular carrier 24 is compared with triangular modulated waves 31-33 to form a modulation signal. When the frequency of the inverter is out of the prescribed frequency range, the triangular carrier and a sinusoidal modulated wave are compared to form a modulation signal. When the triangular wave is used for the modulated wave as described above, the induction defect in the frequency range of the inverter can be prevented. |
