| 摘要 |
<p>PURPOSE:To enable to stop an abnormal electric vibration at DC side by stepwisely varying the frequency of an inverter in the vicinity of an input filter resonance frequency when the frequency of the inverter varies. CONSTITUTION:The speed of an electric motor vehicle is controlled by controlling an induction motor 8 by a variable voltage and variable frequency inverter 7 which receives a DC power source voltage through an input filter 4. An induction motor rotating frequency FM and inverter frequency FINV to speed are shown in a graph. The frequency fINV varies from speed 0 to V2 along three curves f1, f2 and f3, but in this case the frequency starts from the minimum frequency fST, maintains the frequency for a while and stepwisely increase to the value which generates no resonance larger than the resonance frequency f0 of the input filter 4 as designated by the curve f3. In this manner, the abnormal electric vibration at the DC input side can be stopped at the inverter.</p> |
