Superlow-speed pre-estimator control algorithm for closed-loop stepping motor

Abstract

The invention discloses a superlow-speed pre-estimator control algorithm for a closed-loop stepping motor, and relates to the field of the electrical technology. A counter is added to controller software on the basis of a conventional M / T speed measurement method, and whether the rotating speed decreases in each speed loop sampling period or not is judged, thereby achieving the updating of the rotating speed in a compensation pre-estimation mode. When the motor operates at a superlow speed, the method can achieve the minimizing of the speed detection dead time through the rotating speed pre-estimator of the software algorithm under the condition that the coder cost is not improved. The algorithm prevents the speed from being out of control, reduces the low-speed vibration, and improves the superlow-speed performances of a closed-loop stepping driver.

Description

Technical field [0001] The invention relates to the field of electrical technology, in particular to a control algorithm of an ultra-low speed predictor of a closed-loop stepper motor. Background technique [0002] The two-phase closed-loop stepper motor uses the feedback information of the incremental encoder installed on the motor shaft to perform vector control. The speed feedback obtained by the encoder has a great impact on the performance of the entire control system. The general speed measurement method is M Method, T method, M / T method. The M method is to count the encoder pulse number in a fixed time. Because the number of pulses in the measurement time at low speed becomes less and the quantization error becomes larger, the speed measurement accuracy of the M method at low speed is low. The T method is to measure the time interval between two pulses of the encoder. At high speed, the measured time interval becomes less and the quantization error becomes larger, so the ...

AI Technical Summary

Problems solved by technology

However, in the case of ultra-low speed, the encoder pulse interval time exceeds the speed sampling period, and the number of encoder pulses obtained in each speed sampling period is very small, even less than one pulse, and the speed detection stagnates at a certain speed value. , leading to problems such as speed out of control, low-speed oscillation, and poor low-speed performance

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