SU404110A1 - CONVERTER OF SIGNALS OF A SINUS-COSINUS SENSOR INTO A PHASE SHIFT - Google Patents

Description

one

The invention relates to digital-to-digital converters and can be used in angle-to-code converters.

A known converter of sine-cosine sensor signals into phase shift, comprising a sine-cosine sensor, modulators, summing and subtracting devices, phase-sensitive detectors and filters. In such a converter, the secondary windings of a sine-cosine sensor are connected to the inputs of the modulators, and the outputs of the summing and subtracting devices are connected to the inputs of phase-sensitive detectors.

However, when using a known angle-phase-code device in the case of a relatively low frequency of the sinus-cosine transducer, the conversion time is longer. This is due to the fact that the carrier frequency in a known transducer must significantly exceed the frequency of the envelope. For example, at a sensor supply frequency of 1000 Hz, the conversion time exceeds 10 ms (the carrier frequency is more than 10 times the frequency of the envelope).

The purpose of the invention is to increase the speed of the device.

The goal is achieved by the fact that the sine-cosine sensor outputs are connected to the signal inputs of phase-sensitive detectors, the outputs of which are connected to the second inputs of modulators.

FIG. 1 shows a block diagram of the proposed device; in fig. 2 - voltage plots at the output of a two-phase voltage source.

The device consists of a sine-cosine sensor 1, phase-sensitive detectors 2 and 3, modulators 4 and 5, a two-phase voltage source 6, a summing device 7, a subtracting device 8, filters 9 and 10 The device operates as follows. The input is the primary winding of the sine-cosine sensor 1 and the reference inputs of phase-sensitive detectors (PSD) 2 and 3 — an alternating sinusoidal voltage is applied. Variable voltages are removed from the output of the sine and cosine windings

the amplitude of which is proportional to the sine and cosine, respectively, of the angle of rotation of the rotor of the sensor. The indicated voltages are applied to the signal inputs of the PSF 2 and 3. Output voltages of the PSD are supplied to the pa inputs

modulators 4 and 5. The modulators are controlled by a two-phase voltage source of the form square wave (see Fig. 2). The voltages from the outputs of the modulators are added and subtracted among themselves on the summing and subtracting

devices 7 and 8, the outputs of which are connected to the inputs of filters 9 and 10. The voltages on the sine and cosine windings of the sensor can be written as - f / mi sin a sin u) /, and g, 2-С08а-8ШШ /, where and t, k and t, - voltage amplitudes; a is the angle of rotation of the sensor rotor; co - angular frequency of the sensor supply voltage. At the output of the PDP, they have the voltage PFD, - AFPh,, n1 sin a, ifchy, Lfcd -f / nj-cosa, where / Sfcd, and KFchYag are the transmission coefficients of the FFD. After modulation at the output of the modulators 4 and 5, voltages are obtained, - LMG SPL. „N Sin and S ° n tais ... - sin / CQ,: / Sig APBD. -f / ms-COSa - where / (MI and / CM2 are modulators transfer factors; Q is the modulation frequency ("meaddra). Taking into account that in the ideal case Hm, - Am, Am),: fy ,,,, - and t, are obtained at the output of the summing and subtracting devices 7 and 8, respectively, of the voltage - / See APPD - and J sin a. - cos / rQ + / С and V sinKQf - | - COS а sinа V - cosA2 + р - / С „- / SFcd„, + cosa V - sinAQ. riioJ After the separation of the first harmonic in the filters 9 and 10, they receive voltage at their outputs (F1-K, -CFcs / Cf U, n (sln COS Q /: + + cos a -Sin 2 /} C-Cfcha-Cf: -VXX sin (W + a); Dm AFChD Dfa (cos and Sin 2 - sin Q L cos a) - / G "- / Gfchd- / Sf," XX sin (Q t - a), where the transmission coefficients of filters Thus, the output of the device produces two voltages that are out of phase by a double value of the angle of rotation of the rotor of the sensor. As follows from the formulas, the proposed device has no restrictions on the ratio of the frequencies oo and 2. Consequently, the frequency of the voltage Q ( ) can be any The conversion time of the sine-cosine sensor to phase shift, containing phase-sensitive detectors, the on-screen inputs of which are connected to the input of the sine-cosine sensor, modulators, for the first time the inputs of which are connected to a two-phase power source of the "square wave" type, and the outputs to the inputs of the summing and subtracting devices, the outputs of which are connected to filters, characterized in that, in order to increase the speed The device, the signal inputs of the phase-sensitive detectors are connected to the outputs of the sine-cosine sensor, and the outputs of the phase-sensitive detectors are connected to the second inputs of the modulators.

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