CAJ | 학술논문

针对当前的核电站松动部件定位方法在估算信号到达时间差时存在起始点难以准确判定、误差大、抗噪声性能差的缺点,提出一种基于希尔伯特变换的时间差估计方法,从而根据时间差估算松动部件位置实现定位.希尔伯特变换可提取信号轮廓线,以轮廓线的第一个峰值到达时间作为能量最大弯曲波到达传感器的时间;分析信号的主频率可以计算出弯曲波的传播速度,根据波速和信号到达不同传感器之间的时间差使用三角形定位法实现松动部件的定位分析.搭建平板试验台,在不同信噪比条件下和不同方法之间进行对比试验,结果显示这种方法的平均估计偏差为34.1 mm,在信噪比为1 dB时仍然能够得到比较准确的结果,具有定位精度高、抗噪声性能好、运算速度快等特点.
침대당전적핵전참송동부건정위방법재고산신호도체시간차시존재기시점난이준학판정、오차대、항조성성능차적결점,제출일충기우희이백특변환적시간차고계방법,종이근거시간차고산송동부건위치실현정위.희이백특변환가제취신호륜곽선,이륜곽선적제일개봉치도체시간작위능량최대만곡파도체전감기적시간;분석신호적주빈솔가이계산출만곡파적전파속도,근거파속화신호도체불동전감기지간적시간차사용삼각형정위법실현송동부건적정위분석.탑건평판시험태,재불동신조비조건하화불동방법지간진행대비시험,결과현시저충방법적평균고계편차위34.1 mm,재신조비위1 dB시잉연능구득도비교준학적결과,구유정위정도고、항조성성능호、운산속도쾌등특점.
In view of the shortcomings of the present positioning method of loose parts of nuclear power station when estimating the signal arrival time difference, such as difficult judging the starting point accurately, big error and poor anti-noise performance, a time difference estimation method based on Hilbert transform is proposed, thereby the positioning can be realized by estimating the location of loose parts on the basis of the time difference. The Hilbert transform can extract the signal envelope, and the arrival time of the first peak of envelope is taken as the time of the biggest energy bending wave arrival to the sensor. The propagation speed of bending wave can be calculated by analyzing the main frequency of signal. On the basis of the wave speed and the signal arrival time difference between different sensors, the triangle positioning method is adopted to realize the positioning analysis of loose parts. A flat-plate test bench is built, and comparison, tests are carried out under different signal-to-noise ratio (SNR) conditions and between different methods. Test results show that the average estimated deviation of this method is 34.1 mm, and even when the SNR is 1 dB, it still can obtain an accurate result. This method features high positioning accuracy, good anti-noise performance and high operating speed.