Protection circuit, wireless power transfer system and overcurrent/short circuit protection method

Abstract

A protection circuit possessing an enabled output function is provided. The circuit comprises an enabled unit used for controlling whether an unit to be protected can work and an enabled signal output unit used for outputting an enabled signal to the enabled unit. The enabled signal output unit is connected to an output terminal of a comparator U2 so as to output a high level or low level signal so that rapid reaction can be made for over-current and short-circuit faults. A wireless power transmission system applying the protection circuit and a short circuit protection method are also provided. The protection circuit is cooperated with a DC / DC circuit possessing an enabled function so as to carry out cooperation work. A method of carrying out over-current / short-circuit protection through cooperation of software and hardware is provided. An advantage of a rapid reaction speed is possessed. On one hand, corresponding speeds of the over-current and short-circuit faults can be increased and a risk for a device to be burnt out is reduced; on the other hand, the over-current and short-circuit faults possess dual protection.

Description

technical field [0001] The invention belongs to the technical field of circuits and wireless charging systems, and relates to a protection circuit with an overcurrent / short circuit protection function, a wireless power transmission system with an overcurrent / short circuit protection function, and an overcurrent / short circuit protection method. Background technique [0002] Overcurrent and short circuit problems are one of the most common safety problems faced by electrical systems, which will cause the electrical system to be burned and affect the service life of the electrical system. [0003] Take wireless charging systems as an example. In recent years, wireless charging technology has developed rapidly. Because of its non-contact, wire-free connection, and convenient operation, it has attracted the attention of various manufacturers, and various wireless charging products have also come out one after another. On the whole, a complete wireless charging system consists of...

AI Technical Summary

Problems solved by technology

The traditional over-current / short-circuit protection mostly uses fuses for protection, but this method has many disadvantages. First, once an over-current / short-circuit fault occurs, the fuse burns out, and the fuse needs to be replaced manually before it can continue to be used. Second: replace it with a new one each time. Fuses add another cost

Nowadays, many overcurrent / short circuit protections use the AD sampling method to sample the output current into the MCU, and the MCU controls the opening and closing of the circuit through software. This method can basically effectively protect the circuit when a general overcurrent situation occurs, but When the output is short-circuited, a very large current will be generated in an instant. At this time, the software control through sampling and then entering the MCU often cannot close the circuit in time, and the device is often burned before the protection is performed.

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