电极损耗分层预变形补偿方法

为了提高大损耗量条件下电火花成型加工(DEDM)的精度,提出一种基于初始形状预变形的电极损耗补偿方法.分析电极损耗预变形补偿基本原理,建立以相对体积损耗比为基础的电极损耗量模型.在非均匀有理B样条曲线(NURBS)三维表征的基础上进行电极曲面的离散;根据单次放电损耗量与总损耗量的线性关系,提出基于放电间隙的等损耗非均匀的分层补偿方法;构建基于平均曲率的偏移长度和基于伺服进给的偏移方向的计算模型,得出补偿矢量.结合能量法和遗传算法进行曲面光顺,并建立电极损耗的预变形补偿流程模型,计算电极的预变形形状.算例和实验结果表明,采用该方法补偿后的电火花成型加工产生的平均几何误差小于30μm,有助于实现精密加工.

基于分层误差补偿的航空发动机立柱式柔性装配工装定位研究

定位是航空发动机立柱式柔性装配工装中的重要环节,现行方法在实际应用中定位误差比较大,无法达到预期的定位效果,针对现行方法存在的不足和缺陷,提出基于分层误差补偿的航空发动机立柱式柔性装配工装定位研究。采用双目摄影测量法对立柱式柔性装配工装空间位置测量,根据理想位置平面方程估测工装定位误差,采用分层误差补偿技术对定位误差进行线性补偿与非线性补偿,修正工装定位坐标,完成航空发动机立柱式柔性装配工装定位。实验结果表明,在设计方法应用下工装定位误差在1mm以内,能够实现对航空发动机立柱式柔性装配工装精准定位。

A method for absorption compensation based on adaptive molecular decomposition

In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncation and interference which usually exist in the common time-frequency absorption compensation method.Based on the assumption that the amplitude spectrum of the source wavelet is smooth,we first construct a set of adaptive Gabor frames based on the time-variant properties of the seismic signal to transform the signal into the time-frequency domain and then extract the slowly varying component（the wavelet＇s time-varying amplitude spectrum） in each window in the timefrequency domain.Then we invert the absorption compensation filter parameters with an objective function defined using the correlation coefficients in each window to get the corresponding compensation filters.Finally,we use these filters to compensate the timefrequency spectrum in each window and then transform the time-frequency spectrum to the time domain to obtain the absorption-compensated signal.By using adaptive molecular decomposition,this method can adapt to isolated and overlapped seismic signals from the complex layers in the inhomogeneous viscoelastic medium.The viability of the method is verified by synthetic and real data sets.

多层板涨缩性层偏改善方法及监控方式解析

随着线路板压合结构的复杂化,差异较大的内层芯板常被设计在一起。但由于芯板特性,工艺流程,菲林涨缩的差异,会导致在压合过程中,芯板由于伸缩比例不一致,而出现层间对准度偏移,以致内短报废的风险。本文通过对此类叠构层偏失效模式分析、验证,最终确认真因是由于层间涨缩差异导致。而针对涨缩性层偏,本文详细介绍了分层补偿方法,原则,相关治工具孔平移,两组同心圆层偏监控方式等,并将这一套改善对策导入实验板进行验证,最终得出本文介绍的涨缩性层偏改善方法及监控方式对改善层间涨缩性层偏有效,且效果明显。

高阳县全网无功优化及控制系统技术探析

通过采用无功优化及控制系统技术措施,从整个农村电网角度如能实现分级补偿,实时、智能、无功动态就地平衡,进行综合电压、无功控制,才能达到农村电网全网最优改善各节点电压水平和减少网损的目的。该文介绍了高阳供电公司应用新技术、新设备开展农村电网全网无功优化及控制相关工作的做法和体会,与同行交流切磋。

Compensation/consumption hierarchical control strategy based on wind-solar-hydrogen coupling grid connection

In the process of grid-connected wind and solar power generation,there are problems of high rate of abandoning wind and light and insufficient energy.In order to solve these problems,we construct a grid-connected wind-solar hydrogen storage(alkaline electrolyzer(AE)-hydrogen storage tank-battery-proton exchange membrane fuel cell(PEMFC))coupled system architecture.A grid-connected compensation/consumption hierarchical control strategy based on wind-solar hydrogen coupling is proposed.During the grid-connected process of wind and solar power generation,the upper-level control allocates power reasonably to the hydrogen energy storage system by dispatching the power of wind and solar power generation.At the same time,the control strategy ensures that the pressure of the hydrogen storage tank is within the safety range limit,and the lower control completes the control of the duty cycle of the converter in the system.Due to the randomness of wind and light,the hydrogen energy storage system is divided into three working conditions,namely compensation,balance and consumption,and five working modes.The simulation results show that the hydrogen energy storage system compensates for 40%of the power shortage,and consumes 27.5%of the abandoned wind and solar energy,which improves the utilization rate of clean energy.

不同深度注水管柱组合配套研究与应用

目前分层注水井占水井总数的36.7%。分层注水管柱在井内及生产过程中,由于受到油层深度,自身重量、井内温度以及注入压力等诸多因素变化的影响,会产生虎克效应、温度效应、活塞效应、膨胀效应和弯曲效应,导致注水管柱受到轴向压缩力和伸长力的作用。为有效延长分层注水管柱的工作寿命,提高分层注水效果,降低开发成本,我们推广应用了锚定补偿分层注水管柱。