Method and system for detecting state of MOS tubes

Abstract

The invention provides a method and a system for detecting the states of MOS tubes, and relates to the field of electronics. The method comprises the steps of: controlling a voltage circuit, applyinga pulse voltage to the gates of a plurality of MOS tubes according to a preset sequence, judging whether current flows through a bus, and determining the states of a plurality of upper arm MOS tubes and a plurality of lower arm MOS tubes according to the condition of the current on the bus, wherein the magnitude of the current on the bus is determined the lengths of on-times of the plurality of upper arm MOS tubes and the plurality of lower arm MOS tubes. According to the scheme provided by the invention, no single detection circuit is needed, furthermore, the detection current is very small,the detection time is relatively short, the service lives of the MOS tubes are not lost while ensuring the accuracy of detecting the states of the MOS tubes, the entire method for detecting the MOS tubes is completely implemented based on the existing circuit structure, thereby being not only simple and fast, but also being low in cost and high in compatibility.

Description

technical field [0001] The invention relates to the field of electronics, in particular to a method and system for detecting the state of a MOS tube. Background technique [0002] The brushless DC motor consists of a motor body and a driver, and is a typical mechatronic product. Brushless motor refers to the motor without brush and commutator (or collector ring), also known as motor without commutator. When the motor was born in the 19th century, the practical motor produced was in the form of brushless, that is, AC mouse Cage asynchronous motor, this motor has been widely used. However, asynchronous motors have many insurmountable defects, so that the development of motor technology is slow. Transistors were born in the middle of the last century, so brushless DC motors that use transistor commutation circuits instead of brushes and commutators came into being. This new type of brushless motor is called electronically commutated DC motor, which overcomes the first Flaws ...

AI Technical Summary

Problems solved by technology

[0003] At present, the widely used DC brushless motor is a three-phase DC brushless motor, and the drive circuit controls the start and rotation of the three-phase DC brushless motor. The existing drive circuit for controlling the three-phase DC brushless motor generally consists of multiple Composed of MOS tubes, and the MOS tube is the core device in the drive circuit, the damage of the MOS tube will have a serious impact on the motor control, ranging from motor failure to normal operation, to causing a short circuit, burning the motor or the circuit board, so in It is very important to detect the MOS tube before the motor runs

[0004] The current method of self-testing MOS tubes not only requires complex detection circuits, but also takes a long time to detect, which will not only affect the use of the motor, but also increase the user's time cost. The service life is seriously affected, which increases the user's use cost and leads to the user's extremely poor sense of use

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