| 摘要 |
An inverter circuit is provided, in which two semiconductor switching elements are arranged in series between the positive pole and the negative pole of a DC source. An AC can be tapped off between the two semiconductor switching elements. The two semiconductor switching elements are controlled by a pulse-width-modulated control signal, it being possible for the duty ratio of this signal to vary temporally, in order to produce a correspondingly time-varying current on the inverter output. Each semiconductor switching element requires a certain switch-off time in order, on occurrence of a command, to be switched from the on position to the off position. The switch-off time increases the risk of short-circuits between the two poles of the DC source. Firing delays can be used to compensate for this. However, these change the predetermined duty ratio, so that the output voltage no longer corresponds to the predetermined target voltage. According to the invention, an output voltage is obtained which corresponds more or less exactly to the target voltage, without the danger of short-circuits occurring, by driving only one of the two semiconductor switching elements, while the other remains blocked. <IMAGE>
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