Motor position detecting circuit utilizing isolating type rotating transformer

Abstract

The invention discloses a motor position detecting circuit utilizing an isolating type rotating transformer, and the motor position detection comprises a decoding chip, a Buffer circuit and a differential signal regulating circuit, wherein the output end of the decoding chip is connected with the input end of the Buffer circuit; the output end of the Buffer circuit is connected with the input end of the rotating transformer; the rotating transformer outputs a sine-cosine differential signal to the differential signal regulating circuit; the sine-cosine differential signal processed by the differential signal regulating circuit is input to the decoding chip; and the Buffer circuit comprises a front end filtering circuit, an operating and amplifying control circuit, a push-pull circuit and a drive protecting circuit. The power amplification of an excitation signal is realized by adopting the Buffer circuit which is powered by a power supply and has protection, thus the isolating type rotating transformer-adopted motor position detecting circuit can adapt to the drive capability of different loads, can realize a large-range change of differential voltage peaks and has the advantages of enhanced circuit stability, strong load adaptability and good interference resistance; and the differential signal regulating circuit with direct current bias can realize level matching between different rotating transformers and different decoding chips, so that the isolating type rotating transformer-adopted motor position detecting circuit has the advantages of simple circuit structure, low cost and wide application range.

Description

technical field [0001] The invention relates to a rotor position detection circuit of a high-power drive motor for a new energy vehicle, in particular to a motor position detection circuit using an isolated rotary transformer. Background technique [0002] In the rotor position detection circuit of the motor, photoelectric encoders and resolvers are commonly used at present. The photoelectric encoder is a sensor that converts the mechanical angular displacement on the output shaft into pulses or digital quantities through photoelectric conversion. A transformer is an electromagnetic sensor used to measure the angular displacement and angular velocity of a rotating object. Compared with photoelectric encoders, resolvers have the advantages of high reliability, high stability, low cost, and insensitivity to environmental factors such as mechanical vibration, temperature, and humidity. A mainstream sensor. [0003] At present, the mainstream structure of the resolver is isola...

AI Technical Summary

Problems solved by technology

[0004] The use of operational amplifiers has the disadvantage of limited amplification capability, while direct use of push-pull circuits or ordinary Buffer circuits has disadvantages such as poor system stability and poor load adaptability.

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