摘要 |
the method involves using an essentially passive low pass filter (5) which electronically reduces an inverter (1) output voltage on the a.c. side to a minimum level. The filter is followed by a regulator (6), esp. an I-regulator, a P-regulator or a PI-regulator, which is connected to a drive circuit (4) for a power semiconducting switch. The regulator effectively sets the d.c. offset to null by delaying or shifting the corresp. switching command. |