| 摘要 |
An inverter system including a controlled direct current (d.c.) power source for providing a variable d.c. voltage to a variable output frequency inverter circuit by way of a suitable d.c. link, includes suitable circuitry for detecting a commutation fault or shoot-through condition within the inverter circuit and for taking appropriate remedial action to correct such condition. The shoot-through condition is determined as a function of the d.c. input current to the inverter circuit and the output alternating current (a.c.) of the inverter circuit. This determination is achieved by comparing signals representing the two currents at a fixed ratio, other than unity (e.g, at a fixed percentage of one to the other) so that the actual margin increases as the currents increase. Preferably a bias is also included in the comparison function so that a minimum differential is always required before a shoot-through determination is made. |
