Hardware anti-shake self-locking circuit capable of preventing misoperation of high-voltage relay

Abstract

The invention relates to the technical field of electric control of new energy automobiles, and discloses a hardware anti-shake self-locking circuit capable of preventing misoperation of a high-voltage relay aiming at the defects of a logic control circuit used for a coil driving circuit of the high-voltage relay at present. According to the circuit, a reset (RESET) pin and a boot loader (BOOTLOADER) pin in a controller CPU are brought into control sequential logic, an enable pin of a bus driving chip is not directly controlled by an I / O pin of the CPU, but is jointly controlled by the reset pin, the boot loader pin and a control enable pin in the CPU in an output way, a truth table is established, a logic expression of an effective control signal is listed, and a logic gate circuit is designed, so the potential safety hazard of misoperation of a relay possibly caused by an uncertain random state of an I / O pin level of a CPU during initial power-on, reset and boot loading program periods is thoroughly eliminated; therefore, the high-voltage relay can complete specified actions strictly according to preset assumption and instructions under any condition.

Description

technical field [0001] The invention relates to the technical field of electric control of new energy vehicles and the field of power system automation, in particular to a hardware anti-shake self-locking circuit capable of preventing malfunction of high-voltage relays. Background technique [0002] At this stage, high-voltage relays have been widely used in high-voltage DC fields such as electric vehicles, hybrid vehicles, fuel cell vehicles, photovoltaic power generation, wind power generation, cloud server power supplies, battery charging and discharging systems, DC voltage power control, and heavy industrial machinery and equipment. The working principle of the high-voltage relay is to control the large voltage and high current by small voltage and small current. The interior is divided into a coil control terminal and a load terminal. When the controller applies a driving voltage to the coil control terminal, the load terminal can be closed or disconnected. The action o...

AI Technical Summary

Problems solved by technology

[0006] However, this logic control circuit has a major safety hazard in practical applications: during the initial power-on (POWER ON RESET), reset (RESET) and boot loader (BOOTLOADER), because the I / O pins of the CPU The level is in an uncertain state, and it can randomly present "high", "low", "high resistance" and various combination level sequences. Such random level sequence signals will cause high-voltage relays to run out of control and malfunction. In these states, the relay will randomly emit the sound of "cracking" armatures constantly pulling in and out, which may lead to electrical safety accidents in severe cases

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