Rotary transformer angle measurement error hardware self-correction system and method

Abstract

The invention relates to a rotary transformer angle measurement error hardware self-correction system and method. The hardware self-correction system comprises a servo control unit, an amplitude correction unit, a phase angle correction unit and an error representation unit. The servo control unit is used for controlling a load to stably rotate according to the command angular speed. The amplitudecorrection unit is used for adjusting the amplitude of sine and cosine signals output by a rotary transformer and eliminating amplitude errors. The phase angle correction unit is used for adjusting the phase difference of sine and cosine signals output by the rotary transformer and eliminating quadrature errors. The rotary transformer error representation unit sends an instruction angular speed to the servo control unit, performs spectral analysis on the calculated angular speed output by the servo controller, and transmits a second harmonic amplitude Amp to the amplitude correction unit andthe phase angle correction unit as a basis for adjusting the amplitude correction unit and the phase angle correction unit. The system and the method are suitable for correcting and compensating the amplitude error and the phase angle error of the rotary transformer, and the angle measurement precision of the rotary transformer can be greatly improved.

Description

technical field [0001] The invention relates to a hardware self-calibration system and method for angle measurement error of a resolver. Background technique [0002] The resolver has high reliability and good adaptability to mechanical and thermal environments, and is widely used in the field of aerospace high-precision angle measurement. [0003] The resolver uses a dedicated demodulation chip to obtain the envelopes of the two AM signals through detection, and then obtains the angular position information through the demodulation algorithm. Ideally, the envelope signal after detection should be a quadrature sine-cosine signal, but due to factors such as asymmetry of the output signal amplitude of the resolver, non-ideal quadrature, inductance harmonics, and phase offset of the carrier reference signal, the detection The final envelope signal often contains DC offset, amplitude asymmetry and phase offset, which will cause large demodulation errors. Resolver demodulation ...

AI Technical Summary

Problems solved by technology

[0004] In summary, due to the inconsistency, non-orthogonality, and waveform distortion (function error) of the resolver output sine and cosine signal amplitudes, the error reflected in the angular velocity is the double frequency of the rotation frequency, which is the main component of the resolver angle measurement error. , which seriously affects the angle measurement accuracy of the resolver, which in turn affects the control accuracy of the servo system

[0005] The existing resolver error correction and compensation method is to use high-precision sensors to calibrate the resolver, and look up the table to compensate according to the calibration value. This process is carried out on the resolver assembly. Position changes, so there is a large compensation error

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