SMART SHORT CIRCUIT PROTECTION SWITCH CIRCUIT FOR MODIFIED WAVE INVERTER

摘要

A smart short circuit protection switch circuit for a modified wave inverter, comprising: a PFC boost unit (10), used for performing boost conversion of an inputted voltage; a short circuit switch unit (20), an input end thereof being connected to an output end of the PFC boost unit (10), and the short circuit switch unit (20) being used for driving the conduction or disconnection of the input end and an output end thereof on the basis of electrical signals received by a control end thereof; an inversion unit (30), an input end thereof being connected to the output end of the short circuit switch unit (20), and the inversion unit (30) being used for inverting the voltage outputted by the short circuit switch unit (20) into an alternating current; a current sampling circuit (50), used for collecting a current signal of a busbar of the inversion unit (30); a smart identification unit (40) connected to an output end of the current sampling circuit (50), the smart identification unit (40) being used for receiving the current signal collected by the current sampling circuit (50), and: when the current signal does not exceed a preset value, issuing a conduction electrical signal to a control end of the short circuit switch unit (20) to command the short circuit switch unit (20) to drive the conduction of the input end and the output end thereof; and, when the current signal is greater than the preset value, issuing a disconnection electrical signal to the control end of the short circuit switch unit (20) to command the short circuit switch unit (20) to drive the disconnection of the input end and the output end thereof. The present short circuit protection switch circuit can improve the capacitive load capacity of the inverter and prevent the inverter from being mistakenly switched off or damaged.