SU1236613A1 - Digital-to-shaft turn angle converter - Google Patents

Abstract

The invention relates to the field of automation and computer technology and can be used to communicate a digital computing device with actuators. In order to improve the accuracy of conversion by eliminating non-orthogonality error and channel transfer coefficients, generator 14 generates periodic, linearly varying as a function of time, codes that arrive at the inputs of the digital adder 15 and blocks 9 and O memory. In the adder 15, the difference between the linearly varying and the input code is formed, which in blocks 1 and 2 of the memory is converted into the sine and cosine codes of this difference. Digital to analogue converters (D / A) 3 and 4 of the output codes of blocks I and 2 form a sinus and cosine voltage supply sine-cosine rotary transformer (SCHMT) 6. SCHWT 6 operates in phase shifter mode, its output voltages in DAC 7 and 8 are multiplied by mutually orthogonal sine and cosine functions of a linearly varying code. In the comparison element 11, the output voltages of the D / A converters 7 and 8 are subtracted. The differential voltage of the element 11 contains a variable component of the double-frequency generator 14, which is delayed by the filter of the element 11, and a constant component that varies sinusoidally as a function of the difference in angular position shaft of SCWT and input code. The constant component of the voltage difference from the output of the element 11 through the servo amplifier 12 is fed to the input of the amp & (Lu soo about

Description

filament element 13, kinematically connected with the shaft of the SSC 6. As a result, the shaft of the S 6 6 comes to a position matched with the input code. In the converter, inequality errors are compensated for

The invention relates to automation and computing and can be used to communicate a digital computing device with actuators.

The aim of the invention is to increase the accuracy of the converter.

The drawing shows a block diagram of the converter.

The converter contains the first 1 and second 2 blocks of memory, the outputs of which are connected to the digital inputs of the first 3 and second 4 digital to analogue converters (DAL), the analog inputs of which are connected to the output of the source 5 of the reference voltage, and the outputs are connected to the first and second primary windings of a sine-cosine rotating transformer (SCHMT) 6, SSCT 6 outputs are connected to the analogue inputs of the third 7 and fourth 8 DACs, digital inputs of which are connected to the outputs of the third 9 and fourth 0 memory blocks, and the outputs are connected to the input AM of element 11 of the mediation, the output of which through the servo amplifier 12 is connected to the input of the actuating element 13, the shaft of which is kinematically connected to the shaft of the SSC 6, the linearly varying code generator 14 is connected to the inputs of memory blocks 9 and 10 and to one group of inputs of a digital adder 15 other groups of inputs, through which code conversion block 16 is connected to input code source 17, and outputs of digital adder 15 are connected to inputs of memory blocks 1 and 2.

The Converter operates as follows.

Linearly variable code generator 14 generates binary equi

of the excitation of excitatory hardness GG, its coag) of transmittance and transfer coefficients of the DAC. Channel mismatch is compensated for by the initial alignment of SCRT 6, or il.

0

five

0

from 5

0

2

the instantaneous values of the angle iJ t, which in blocks 9 and 10 of the memory (chips 505REZE) are converted into the function codes cosiJt and siruJt, respectively. At the output of digital adder 15 (chips 564ro), the argument code iJt-N is formed, which in blocks 1 and 2 of memory (chips 505 CUT) is converted into the code of functions sin (u) t; -N) and cos (cJt-N), respectively. These D / A codes 3 and 4 (572PA1 chips) are transformed into the voltage SQUT 6 (WT-5), which operates in a phase shifter mode, and phase-modulated voltages are induced on its output windings.

 11, „, and, sin (..) t-N +); j. and f,., --- U cos (uJt-N + fW) o After multiplying in DAC 7 and 8 the output signals of SCPT 6 by the codes of mutually orthogonal functions coswt, sinw) t from the outputs of blocks 9 and 10 in the comparison element 11 subtracting the output voltages of the D / A converter 7 and B, resulting in a voltage

 --- i-- sin (-N) +

+ U1. sin (2..jt-n + v). (2)

This voltage contains a constant component proportional to the difference in the angles, one of which is set by the input code N, and the other oi is processed by the actuating element 13, and the variable component of the double frequency 2a. the element 11 of the comparison.

A tracking system consisting of a servo amplifier 12, an actuator element 13, an ACS 6, a DAC 7 and 8, and a reference element 1, by turning

the rotor of the SQUT 6 has turned over the output voltage of the comparison element P, which leads to the equality of the angle oi of the rotation of the SSCT to the specified value N regardless of the amplitude of the output voltages of the SSCT 6.

As a result of the asymmetry of the excitation voltages of the ACS 6, its transformation ratios and the transmission ratios of the D / A converter does not lead to the occurrence of conversion error.

The non-orthogonality of the conversion channels leads to errors such as offset zero, i.e. not dependent on the angle of rotation of the shaft, which is compensated by the initial exhibition of ACS.

The non-compensable source of error in this converter is the display error of the ACST sinus dependence, which determines the achievable conversion accuracy.

Claims (1)

Invention Formula The code converter to the angle of rotation of the shaft containing the source in the drive code. The first and second memory blocks, the outputs of which are connected to the digital inputs of the first and second digital-to-analog converters, respectively, the analog inputs of which are connected to the source output Compiled by A.Smirnov Editor V.Ivanov Tehred I.GTopovkch Proofreader T, Kolb .---- ----------------- Order 3098/58 Circulation 816 Subscription VN1ShPN USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., TSL / 5 Production and printing company, Uzhgorod, ul, Proektna, 4 the reference voltage, and the outputs are connected to the first and second primary windings of a sine-cosine rotary transformer, the shaft of which is kinematically connected to the shaft of the actuator, the servo amplifier, the output of which is connected to the input of the actuator, a code conversion unit that differs. that, in order to improve the accuracy of the converter, a linearly varying code generator, a digital adder, a third and fourth memory blocks, a third and fourth digital-to-analog converters, an element Comparison, the output of which is connected to the input of the servo amplifier, is the generator outputs of a linearly varying code, connected to one group of inputs of a digital adder and inputs of the third and fourth memory blocks, the outputs of which are connected to the digital inputs of the third and fourth digital-to-analog converters, respectively, the analog inputs of which are connected with the corresponding outputs of the sine-cosine rotary transformer, and the outputs are connected to the inputs of the comparison element, the source of the input code through the conversion unit codes is connected to another group of inputs of a digital adder, the output of which is connected to the inputs of the first and second memory blocks.