JPS60177687U - inverter circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

FIG. 1 is a conventional inverter circuit diagram, FIGS. 2 and 3 are current waveform diagrams, and FIG. 4 is an inverter circuit diagram according to an embodiment of this invention. . , In the figure, 2 is an AC induction motor, □
3.3a is an inverter main circuit, 4v4a is an inverter circuit, Q□ to q are power transistors, L is a choke coil, F is a fuse, C is an electrolytic capacitor, and VRl is a varistor. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Scope of utility model registration request] In an inverter circuit that has an inverter main circuit that drives an AC motor equipped with semiconductor switching elements, and a filter circuit that is made up of a choke coil and an electrolytic capacitor and reduces power supply current ripple, the electrolytic capacitor is arranged in series with the electrolytic capacitor. 1 fuse for interrupting overcurrent due to a failure; an element disposed between the power source of the inverter main circuit to suppress the surge voltage generated when the fuse blows to below the withstand voltage of the semiconductor switching element; and at least the above element. An inverter circuit comprising a surge voltage detection circuit that detects surge voltage when a fuse blows and stops operation of an inverter main circuit.