Electronic circuit for obtaining speed signals and data on angles of rotation from a resolver synchro (synchro resolver) using the amplitude method

摘要

The aim of the invention is to be able to use a robust resolver to replace as a whole the multiplicity of check-back (status) devices (commutation sensors, tachogenerators, pulse generators, absolute shaft encoders) have been necessary to date in the case of brushless servomotors and are in part sensitive. The subject-matter of the invention delivers the required signals electronically. The main claim of the invention relates to the fact that the sinusoidal amplitude modulation, required for the low-noise operation of the resolver, of the carrier is performed by phase-controlled scanning of higher-frequency sinusoidal oscillations which can easily be generated. This produces additional advantages with respect to prior (digital) solutions (e.g. using read-only memories with sine tables), chiefly with reference to cut-off frequency, balance quality of the tachometer signals and costs. It is shown in the subclaim that it is even possible on the basis of the invention according to Claim 1 to digitise the angle of rotation without this requiring read-only memories. Furthermore, the invention according to Claim 1 permits preliminary compensation of contouring errors in the case of conversion in the circuit according to Claim 2, which has not previously been possible in the prior direct R/D converters (= resolver/digital converter).