Digital converter for rotary transformer

Abstract

The invention discloses a digital converter for a rotary transformer. The position q and the speed omega of the rotor of a drive motor in an electric vehicle are acquired by performing digital conversion on output signals of the rotary transformer in an electric drive system of the electric vehicle. The digital converter for the rotary transformer is characterized by comprising a digital sine and cosine generator, an excitation voltage generation module, a rotary transformer output signal demodulation module and a position and speed acquisition module. According to the digital converter for the rotary transformer, by the introduction of a sine and cosine wave generator based on a motor controller processor chip and the demodulation of the output signals of the rotary transformer, a time delay phenomenon is eliminated, the cost of the electric drive system of the electric vehicle is reduced, and the acquisition precision of the position and the rotating speed of the electric drive system of the electric vehicle is improved.

Description

technical field [0001] The invention relates to a digital converter, specifically, a rotary transformer digital converter used in an electric drive system of an electric vehicle. Background technique [0002] Resolver, referred to as resolver, is a sensor for measuring the rotation angle. It is gradually used in the field of electric vehicles because of its advantages such as stability, high efficiency, strong resistance to shock vibration and temperature and humidity changes. [0003] The output signal of the resolver is analog, which needs to be converted into a position and speed signal by means of a decoder chip. Currently, the most widely used demodulation solution is to work with AD2S12X series decoder chips from Analog Devices or AUX series decoder chips from Tamagawa. Convert it into digital quantity to realize the interface with control chips such as DSP. That is, the analog signal output by the resolver is sent to the multiplier after AD sampling, and the digital ...

AI Technical Summary

Problems solved by technology

This solution has low demodulation accuracy, and the use of chips such as converters and level shifters and related hardware conditioning circuits increases system complexity and implementation costs. Therefore, the cost, weight, and size of the rotor position and speed acquisition system should be considered , using less hardware to achieve accurate location acquisition has become a development trend

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