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在地震勘探中,为了排除高压输电线的干扰,多年来人们作了不少的探索与努力。开始人们误认为输电线的干扰频率就是50周,后来才发现国内电网的频率是变化的,一般可以从46.5周变化至50.5周。据观察频率随用电量而变化,一般地说耗电量大时频率低,反之耗电量少时频率高。对于上述频率不断变化的干扰,显然固定频率的陷波器是难于奏效的。通常,为了尽量少损失有效波,陷波器的特性曲线总是设计的十分尖锐,因此干扰频率稍有变化,压制效果就变得很差。最近江苏省石油物探研究队又试验推广使用了自动频率跟踪陷波器,这种陷波器能自动跟踪输电线的频率变化,把它的最大衰减点始终对准干扰频率。采
In seismic exploration, in order to eliminate the interference of high-voltage transmission lines, many people made a lot of exploration and hard work. People began to mistakenly believe that the transmission line interference frequency is 50 weeks, and later found that the frequency of domestic power grid is changing, the general change from 46.5 weeks to 50.5 weeks. It is observed that the frequency changes with the power consumption, generally speaking, when the power consumption is high, the frequency is low, whereas when the power consumption is low, the frequency is high. It is obvious that a fixed-frequency notch filter is ineffective for the above-mentioned disturbances of changing frequencies. In general, to minimize the loss of the effective wave, the characteristic of the notch filter is always designed so sharply that the interference frequency changes slightly and the suppression effect becomes poor. Recently, the Jiangsu Provincial Petroleum Geophysical Research Team also experimented with and promoted the use of an automatic frequency tracking notch filter, which can automatically track the frequency change of a transmission line and always align its maximum attenuation point with the interference frequency. Mining