| 摘要 |
PURPOSE:To reduce the overcurrent withstand strength of a rectifier by invaliding a current control due to the input current of an inverter when the inverter is overloaded and raising the voltage of a DC intermediate circuit from a floating charging voltage to a uniform charging voltage. CONSTITUTION:When the output current of a thyristor inverter 18 becomes the prescribed value or higher, an overload detector 42 is operated, a normally closed contact 34 is opened to interrupt a detection current signal from a DC current transformer 30, thereby invaliding a current control system for controlling a thyristor rectifier 10, thereby eliminating the limit of the output current of the rectifier 10. Simultaneously, a normally open contact 24 is closed, and a uniformly charging voltage setter 22 is connected to a voltage control system. Accordingly, the voltage of a DC intermediate circuit is raised to the uniform charging voltage which is higher by 10% than the floating charging voltage from a battery 16. Thus, since the DC voltage decreases, the overcurrent withstand strength of the rectifier 10 can be decreased. |
