Incremental encoder self-diagnosis method and control device

Abstract

The invention provides an incremental encoder self-diagnosis method and a control device, and the method comprises the steps: collecting an electric pulse signal of an incremental encoder, and judging whether the electric pulse signal is triggered or not; if the pulse signal trigger is collected, judging the signal type; if the collected signal is judged to be the A-phase or B-phase pulse signal, detecting whether the Z phase has a fault or not through the A-phase or B-phase pulse signal; if the collected signal is judged to be the Z-phase pulse signal, detecting whether the A phase and the B phase have faults or not through the Z-phase pulse signal; and if the pulse signal trigger is not collected, detecting whether the AB phase and the Z phase have full faults or not through the output power of the motor and the speed of the incremental encoder. According to the method, the self-diagnosis function of the incremental encoder is achieved by analyzing the ABZ phase waveforms of the incremental encoder, all faults of the encoder can be covered, the diagnosis precision can be set, the situation of fault misinformation is avoided, the faults of the incremental encoder can be accurately analyzed, and fault information can be reported in time.

Description

technical field [0001] The invention belongs to the technical field of encoders, and in particular relates to an incremental encoder self-diagnosis method and a control device. Background technique [0002] With the development of control technology, the application of incremental encoders is becoming more and more extensive. From the control of industrial machine tool motors, to the control of robot joint motion, and then to the control of balance vehicles, incremental encoders can be seen. Quantitative encoder as a sensor for measuring speed and angle of rotation, if it fails, there will be unimaginable consequences, so it is particularly important to invent a self-diagnosis method for incremental encoder. [0003] The communication between the incremental encoder and the controller is not through a general communication protocol, but by converting the position change of the encoder into a pulse signal, and the controller uses the pulse signal to judge the rotation angle o...

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Problems solved by technology

[0003] The communication between the incremental encoder and the controller is not through a general communication protocol, but by converting the position change of the encoder into a pulse signal, and the controller uses the pulse signal to judge the rotation angle of the encoder, and the pulse signal cannot contain Fault information, so when the encoder fails, such as disconnection, the controller cannot directly identify the fault. At present, there are relatively few self-diagnosis methods for incremental encoders. Of course, there are also continuous acquisitions through phase A. The signal reaches a certain threshold to judge the disconnection of phase B, and the method of judging the disconnection of phase A by continuously collecting the signal of phase B reaching a certain threshold, but this method has a certain possibility of false detection

[0004] When the incremental encoder is used, its self-diagnosis method is not used. Once the encoder fails, the controller will read the wrong angle information, and the control system will have unimaginable consequences. For example, when the robot chassis uses incremental encoding When the controller is used for the closed-loop control of the speed of the wheel motor, if the AB phase is disconnected, the controller controls the wheel motor to rotate at this time, and the speed obtained by the controller is 0. Through the closed-loop control algorithm, the controller will increase the output of the motor so that The wheel speed reaches the set speed, but because the encoder is in a faulty state, the measured speed is always 0, and eventually the device will run off, which is very dangerous

[0005] In the existing incremental encoder self-diagnosis scheme, the disconnection of phase B is judged when the signal continuously collected by phase A reaches a certain threshold, and the disconnection of phase A is judged by the signal continuously collected by phase B reaching a certain threshold. There are disadvantages in the method, and misjudgment may occur. For example, when the encoder rotates continuously in a small range around a certain position, there will be a phenomenon that pulses appear continuously in one phase, and there is no pulse in the other phase. At this time, through the above The method will judge that the encoder is faulty, but it is not faulty; and the existing incremental encoder is invalid for the situation that the ABZ phase is completely broken

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