| 摘要 |
1,036,464. Inverting; control of A.C. motors. LICENTIA PATENT - VERWALTUNGSG.m.b.H. April 5, 1963 [April 5, 1962], No. 13623/63. Headings H2F and H2J. An inverter is operated at a comparatively high frequency and pulse width modulated at a lower frequency so that the output contains a lower-frequency component which may be filtered out to supply a load such as a motor. The waveforms obtained are shown in Fig. 2b, in which the solid line represents the output before filtering and the dotted line the output after filtering. In Fig. 1 (not shown), the inverter 1 supplies a load 3 through a filter comprising inductance 4 and capacitance 5, and a control voltage at the lower frequency is applied to the inverter at 1f. If the load current departs from a sinusoid this is detected at 7 and a correcting signal is applied to the inverter at 1a. |
