FAIL-SAFE APPARATUS FOR INVERTER

摘要

There is provided a fail-safe apparatus for an inverter that can suppress the voltage of a DC power source from rising when the voltage of the DC power source becomes excessive, due to an abnormality caused in an inverter that performs driving and electric-power generation by use of a synchronous motor in which a permanent magnet is utilized as a magnetic-field magnet. The fail-safe apparatus for the inverter includes an excessive voltage detection circuit for detecting a state of excessive voltage while monitoring the voltage of the DC power source of the inverter and a drive switching circuit for switching a driving method for a semiconductor switching device between three-phase PWM driving and three-phase short-circuiting driving in accordance with the state of an excessive voltage detection circuit.

主权项

1. A fail-safe apparatus for an inverter that performs driving and electric-power generation by use of a synchronous motor in which a permanent magnet is utilized as a magnetic-field magnet, the fail-safe apparatus for the inverter comprising:
a switching circuit that has a switching device for performing electric-power conversion; an excessive voltage detection circuit that detects an excessive voltage by monitoring a DC power source voltage of the inverter; and a drive switching circuit that switches a driving method for the switching device between three-phase PWM driving and three-phase short-circuiting driving, in accordance with an excessive voltage determination signal from the excessive voltage detection circuit.