基于反正弦函数加速收敛的新型有源滤波器锁相环

为保证指定次谐波补偿有源滤波器(Active Power Filter,APF)取得更好的补偿效果,主要研究了有源滤波器的锁相环(Phase Locked Loop,PLL)技术。本文根据dq变换原理,提出了一种基于反正弦函数加速收敛的新型有源滤波器锁相环技术。该技术在误差范围内,可实现绝大部分相位偏移范围内的1次调节锁相。与传统的基于dq变换的锁相环技术相比,新型锁相环技术具有明显的速度优势和灵活性。最后,仿真与实验结果验证了上述分析的正确性。     

交流滤波器差动保护的研究

本文根据直流输电中交流滤波器自身的特点,提出一种有别于常规差动的差动动作判据,阐述了该差动保护的计算整定,并分析此判据下交流滤波器在各种故障下差动保护的动作行为。同时,辅以南方电网在许继集团的交流滤波器保护装置RTDS试验中的数据和波形为佐证。综合分析后得出,该差动保护判据可以很好地应用于直流输电中的交流滤波器差动保护。     

New rapid transfer alignment method for SINS of airborne weapon systems

Transfer alignment is an effective alignment method for the strapdown inertial navigation system （SINS） of airborne weapon systems. The traditional transfer alignment methods for large misalignment angles alignment use nonlinear transfer align- ment models and incorporate nonlinear filtering. A rapid transfer alignment method with linear models and linear filtering for ar- bitrary misalignment angles is presented. Through the attitude quaternion decomposition, the purpose of transfer alignment is converted to estimate a constant quaternion. Employing special manipulations on measurement equation, velocity and attitude linear measurement equations are derived. Then the linear trans- fer alignment model for arbitrary misalignment angles is built. An adaptive Kalman filter is developed to handle modeling errors of the measurement noise statistics. Simulation results show feasibili- ty and effectiveness of the proposed method, which provides an alternative rapid transfer alignment method for airborne weapons.     

Self-alignment of full skewed RSINS：observability analysis and full-observable Kalman filter

Traditional orthogonal strapdown inertial navigation sys-tem （SINS） cannot achieve satisfactory self-alignment accuracy in the stationary base： taking more than 5 minutes and al the iner-tial sensors biases cannot get ful observability except the up-axis accelerometer. However, the ful skewed redundant SINS （RSINS） can not only enhance the reliability of the system, but also improve the accuracy of the system, such as the initial alignment. Firstly, the observability of the system state includes attitude errors and al the inertial sensors biases are analyzed with the global perspective method： any three gyroscopes and three accelerometers can be assembled into an independent subordinate SINS （sub-SINS）;the system state can be uniquely confirmed by the coupling connec-tions of al the sub-SINSs;the attitude errors and random constant biases of al the inertial sensors are observable. However, the ran-dom noises of the inertial sensors are not taken into account in the above analyzing process. Secondly, the ful-observable Kalman filter which can be applied to the actual RSINS containing random noises is established; the system state includes the position, ve-locity, attitude errors of al the sub-SINSs and the random constant biases of the redundant inertial sensors. At last, the initial self-alignment process of a typical four-redundancy ful skewed RSINS is simulated： the horizontal attitudes （pitch, rol ） errors and yaw error can be exactly evaluated within 80 s and 100 s respectively, while the random constant biases of gyroscopes and accelero-meters can be precisely evaluated within 120 s. For the ful skewed RSINS, the self-alignment accuracy is greatly improved, mean-while the self-alignment time is widely shortened.     

基于MATLAB的IIR数字滤波器的研究

本文介绍了基于Matlab的滤波器设计分析工具（FDATool）的IIR数字滤波器的设计,并通过仿真对所设计的数字滤波器进行验证,达到滤波器设计的最优化。通过实例证明了本方法的可行性和实用性,具有一定的工程应用价值。     

无功补偿与谐波抑制

文章介绍了并联电容器与谐波的相互影响的原理，谐波的抑制方法，以及谐波的隔离和实际应用中的处理，重点介绍了并联电容器对谐波的放大。串联电抗器谐波滤波器的原理以及无功补偿与谐波处理相结合的方法。     

采用可编程逻辑器件实现数字滤波

介绍了一种利用ALTERA公司的复杂可编程逻辑器件（CPLD）快速卷积法实现数字滤波器的设计。     

BUF634在高频滤波器中设计方法的实现与改进

本文介绍了某型飞机机载高频滤波器的设计方法与工作原理,在此基础上对芯片BUF634的使用方法进行了阐述,并对实际应用中存在的问题进行分析,提出了改进方法。实验验证证明,该方法简单有效,适用范围广。     

轧机偏心补偿控制信息相域滤波提取方法

在深入分析机架偏心作用机制的基础上,提出了轧机偏心补偿控制信息相域滤波提取方法,它利用机架偏心轧制作用强度与轧制过程中轧辊的机械转动相位密切相关的特点,将轧机的时域轧制数据转换为以轧辊转动相位为参变量的数据进行处理.在线性化相域空间中,与轧辊偏心作用相关的信号呈现出显著的周期化特征,而其余的原时域周期信号在转换过程中均被非周期化.在线性化相域空间中,将轧辊转动轧制作用的往复周期作为指定的循环统计量统计周期.理论分析表明,基于统计方法能够有效地消除噪声的影响,同时抑制非指定线性化相域循环分量,实现机架偏心特性信息的有效获取,其实质是线性化相域空间中的梳状滤波器滤波.依据统计获取的机架偏心特征信息可以为轧机偏心补偿提供一定的数据参考.