frequency variation

Research on steady-state overreach of power frequency variation distance relay

工频突变量距离继电器稳态超越的研究

With the application of auto-regressive integrated moving average algorithm, sampling frequency can trace the frequency variation of measured signal, which can realize complete alternation sampling.

运用广义预测方法，使采样频率跟踪被测信号频率的变化，实现整周期采样，保证测量精度。

The laser feedback interference in λ/ 4 phase-shifted index-coupled and gain-coupled Distribute Feedback laser diodes is analyzed. The threshold gain and oscillation frequency variation in DFB laser diode are theoretically deduced, and present the expression of complex feedback sensitivity.

分析了λ/4相移折射率耦合型及增益耦合型分布反馈激光器的自混合干涉效应，推导出分布反馈激光器的增益及频率的变化，并给出复反馈灵敏度系数表达式。

Weak frequency variation detection based on chaos' resonant frequency-locking characteristic

基于混沌共振锁频特性提取微弱频率变化

For Shanghai power grid, which has large short circuit capacity and short electrical distance, a method using imported instrument to test power frequency variation distance protection is presented.

结合上海电网具有短路容量大、电气距离短的特点，提出了使用进口仪器测试工频变化量距离保护的具体方法。

The frequency variation filtering technique is applied to extract the fundamental surface wave signal from the records based on long period Rayleigh surface wave data from Chinese Digital Seismological Network ( CDSN).

根据中国数字化台网（CDSN）记录到的长周期Rayleigh面波资料，使用频变滤波技术从记录中提取基阶振型面波信号；

Transformation of Speed Control System by Frequency Variation in Cooling of Sintering Conveyor Belt

烧结带冷变频调速控制系统改造

Precursor Information in Frequency Variation before Strong Earthquake of Guangxi Province History

广西历史强震前地震频度变化的震兆信息

To use frequency variation to regulate the speed of navigation lock gate, reducing the gate crush due to improper position of the position limit switch and enabling the lock gate more stable in speeding up and down.

在船闸闸门调速中采用变频调速，减轻了闸门因限位开关位置不当等原因造成闸门碰撞，使闸门运行中加减速更加平稳。

LNB Frequency Variation and Emergency Measures Along with Environment

LNB本振随环境的变化及应变措施