半球谐振陀螺控制电路频率跟踪精度提升方法

Approach to Improve the Frequency Tracking Accuracy of the HRG Control Circuit

半球谐振陀螺控制电路的控制精度直接影响半球谐振陀螺仪的输出精度,而频率跟踪精度又直接影响了半球谐振陀螺控制电路的精度。传统的半球谐振陀螺数字控制电路采用过零比较的方法计算陀螺幅点信号的频率,此方法易受地线毛刺信号的干扰,频率跟踪精度不高。介绍了采用A/D转换采集数据估算陀螺幅点信号频率的方法,并对各种方法进行了优缺点比较,提出选用建议。这些方法既提升电路抗干扰能力,又大幅提升了频率跟踪精度,还省去了过零比较电路。分析及测试结果表明,采用该频率跟踪方法,半球谐振陀螺的频率跟踪精度可达0.002Hz,可大幅提升半球谐振陀螺控制电路的精度。

The accuracy of the hemispherical resonant gyroscopes (HRG) is affected by the control circuit accuracy directly,and the control circuit accuracy is affected by the tracking frequency accuracy.The frequency of the gyroscope's amplitude is calculated by the zero-cross detection in the traditional HRG control circuit.Effected by the undesired signal noises from the ground electrode,the frequency tracking is not accurate.The method to estimate the resonant frequency by the A/D convertor was proposed in this paper.And the different solutions following this method are compared to show their merits and demerits.These solutions,not only increase the interference immunity of the HRG,but also simplify the circuits.It is shown that,by using these methods,the tracking frequency accuracy could reach 0.002Hz by the test and analysis,which could improve the control circuit accuracy of the HRG significantly.