Real-time low speed detection device based on virtual sine waves

Abstract

The invention provides a real-time low speed detection device based on virtual sine waves. The device comprises a pulse encoder outputting Ao, Bo, So and Zo four-set pulse signals, a signal conditioning circuit which is a pulse shaping circuit, a sampling conversion module which is a pulse conversion circuit, and a processor, wherein Ao and Bo pulses are equal cycle and equal duty ratio digital pulses, the So pulses are equal cycle and variable duty ratio pulses, the Zo pulses are the zeroing pulses, four input ends of the sampling conversion module are respectively used for receiving the A, B, S and Z four paths of pulse signals, four output ends of the sampling conversion module are for outputting the frequency multiplication pulses AB, the direction signal R, the zeroing signal Z and asine sampling signal S, and an input end of the processor is connected with the four output ends of the sampling conversion module. The device is advantaged in that real-time and rapid rotating speedcalculation is realized, rotating speed measurement precision is higher, moreover, the whole calculation mode employs an interruption and DSP internal counter, the CPU time is not occupied, and the device is especially suitable for directly-driven wind turbines and real-time control systems for speed closed loop.

Description

technical field [0001] The invention belongs to the technical field of signal detection, and in particular relates to a real-time low-speed detection device based on a virtual sine wave. Background technique [0002] In the prior art, there are two speed measurement methods, analog circuit hardware detection and digital circuit calculation speed measurement. With the development of electronic information technology, especially the generation of DSP digital processing chips, the accuracy and range of speed detection have been greatly improved. There are also different methods for digital circuit speed measurement. The initial method is to use the peripheral analog-to-digital conversion chip to convert the analog quantity detected by the analog-digital conversion chip into a digital quantity, and then transmit the digital quantity to the CPU through the bus for calculation. . [0003] Now, with the development of chip technology, an analog-to-digital conversion chip will be ...

AI Technical Summary

Problems solved by technology

[0008] However, no matter it is M method, T method or M / T method, encoder pulse must be required. Encoder pulse must appear twice to calculate and extract the speed, and the speed calculation value is due to 0-1 at the moment when the second pulse appears. There are speed steps or jitters in the change, so it is impossible to quickly extract the speed

[0009] Most of today's equipment and instruments, in real-time systems that use rotational speed as closed control, must require real-time and fast calculation of rotational speed, which cannot be satisfied by existing algorithms

[0010] In addition, for most speed algorithms, only a single detection is performed on the speed signal, and the signal cannot be judged, so the speed system that has tended to be stable drifts slowly until it fails

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