Detection method for line breakage of motor power line in three-phase AC servo drive system

Abstract

The invention discloses a detection method for the disconnection of a motor power line in a three-phase AC servo drive system, that is, the method first cuts off the three power tubes of the upper bridge in the power module through a digital signal processor, and then sequentially turns off the three power tubes of the power module Any one of the three power tubes of the middle and lower bridges is turned on, and the AD conversion sampling circuit is used to collect the remaining two phases of the power tubes of the upper bridge. If the capacitor voltage of one phase does not meet the standard, it is judged that the power line of the motor is broken. This method overcomes the defects of traditional motor power line disconnection detection, and is simple, practical, and highly reliable. It can make accurate fault judgments, reduce detection costs, and realize automatic and rapid detection of motor power line disconnection in servo drive systems. , Low-cost detection.

Description

technical field [0001] The invention relates to a detection method for a broken wire of a motor power line in a three-phase AC servo drive system. Background technique [0002] The servo drive system is an important drive execution control mechanism of the automation control system, which consists of a servo drive and a servo motor. Once the power line of the servo motor is disconnected, the servo drive will not be able to transmit the driving voltage to the servo motor, causing the servo motor to lose control. If the fault cannot be detected in time and alarm protection measures can be taken, it will have a major impact on the entire servo drive system . [0003] The servo drive system is an electric transmission automatic control system composed of the motor as the control object, the digital signal processor as the core, and the power electronic power conversion device as the executive mechanism under the guidance of the automatic control theory. parts, such as figure ...

AI Technical Summary

Problems solved by technology

[0005] For the disconnection fault of the power line of the servo motor, it is usually identified through the AD conversion sampling circuit to detect whether the output current of the power module is zero. In both cases, the current of the motor is near zero, which is difficult to distinguish, and it is very easy to cause false alarms, which affects the normal and reliable operation of the servo drive system

There is also a low-resistance measuring device installed at the output end of the power module to detect whether the servo motor is disconnected by measuring the resistance value, but this will greatly increase the cost of the system, which is not conducive to automatic, fast and low-cost faults in the servo drive system detection

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