Short-circuit protection circuit of electric vehicle

Abstract

The invention relates to a short-circuit protection circuit of an electric vehicle. The short-circuit protection circuit comprises a sampling component (1), a switch assembly (2), an electric lock switch controller (3), a sampling comparator (4), an overload control and self lock (5), a fault indicator (7) and an electric lock switch (8), wherein the sampling component (1) and the switch assembly(2) are connected in series between a negative electrode GND of a storage battery and a ground line LGND of a load, an enhanced NMOS field-effect transistor is used as an electronic switch, a grid isconnected with outputs of the electric lock switch controller (3) and the overload control and self lock (5), the load is circuit-shorted, the overload control and self lock (5) outputs a low level sothat the electronic switch is switched off, the fault indicator LED is turned on, the state is self-locked, a fault is removed, unlocking can be achieved by switching off and switching on the electric lock switch (8), and normal working is restored. The short-circuit protection circuit has the advantages of classified protection, rapid switch-off protection speed and the like and is convenient and simple to unlock.

Description

technical field [0001] The invention relates to a protection circuit, in particular to a short-circuit protection circuit for the output of an electric vehicle power supply. Background technique [0002] On electric vehicles, in order to prevent power overload or short circuit, most of them are equipped with air switches. The principle of the air switch is that when it is working normally, press the operating mechanism to connect the circuit. When the line is generally overloaded, although the overload current cannot make the electromagnetic tripper operate, it can make the heating element generate a certain amount of heat, prompting the bimetal sheet to bend upward when heated, and push the lever to disengage the hook and the lock, and the main contact When the circuit is short-circuited or seriously overloaded, the short-circuit current exceeds the instantaneous trip setting current value, and the electromagnetic tripper generates a large enough suction force to attract t...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the deficiencies of the prior art, the present invention provides an electric vehicle power supply short-circuit protection circuit that senses the overload current of the total circuit, automatically controls the semiconductor electronic switch to turn off the power supply, and utilizes the electric lock switch installed outside the electric vehicle to unlock and reset , to solve the problems of long power-off action time, inconvenient unlocking and reset, etc.

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