Electrical structure identification of deep shale gas reservoir in complex structural area using wide field electromagnetic method

To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the conventional electromagnetic method in exploration depth,precision,and accuracy,the large-depth and high-precision wide field electromagnetic method is applied to the complex structure test area of the Luochang syncline and Yuhe nose anticline in the southern Sichuan.The advantages of the wide field electromagnetic method in detecting deep,low-resistivity thin layers are demonstrated.First,on the basis of the analysis of physical property data,a geological–geoelectric model is established in the test area,and the wide field electromagnetic method is numerically simulated to analyze and evaluate the response characteristics of deep thin shale gas layers on wide field electromagnetic curves.Second,a wide field electromagnetic test is conducted in the complex structure area of southern Sichuan.After data processing and inversion imaging,apparent resistivity logging data are used for calibration to develop an apparent resistivity interpretation model suitable for the test area.On the basis of the results,the characteristics of the electrical structure change in the shallow longitudinal formation of 6 km are implemented,and the transverse electrical distribution characteristics of the deep shale gas layer are delineated.In the prediction area near the well,the subsequent data verification shows that the apparent resistivity obtained using the inversion of the wide field electromagnetic method is consistent with the trend of apparent resistivity revealed by logging,which proves that this method can effectively identify the weak response characteristics of deep shale gas formations in complex structural areas.This experiment,it is shown shows that the wide field electromagnetic method with a large depth and high precision can effectively characterize the electrical characteristics of deep,low-resistivity thin layers in complex structural areas,and a new set of low-cost evaluation technologies for shale gas target layers based on the wide field electromagnetic method is explored.

广域电磁法在强干扰碳酸盐岩矿区的应用探索

目前中国各成熟矿山大多面临浅部资源量不足的危机,对深部资源勘探的需求在不断增强。在实际勘探应用中,除了要进行大深度高精度探测,还要克服复杂地形与强电磁干扰的影响,因此对勘探技术提出了更高的要求。本文采用广域电磁法,在地形复杂且电磁干扰严重的云南某碳酸盐岩矿区开展了应用探索研究。结果认为广域电磁法在复杂碳酸盐岩矿区能够有效地压制干扰,对断层和已知矿体反映明显。据此在矿区深部圈定了可能的矿致异常,为矿区深边部找矿提供了指示方向,在复杂地形强电磁干扰的碳酸盐岩矿区开展攻深找盲探矿工作,广域电磁法能够实现高精度大深度探测,抗干扰能力强,工作效率高,可作为一种深部找探矿的技术手段。

±1100 kV特高压直流穿墙套管交、直流局部放电试验净空区域优化

为准确测量±1 100 kV特高压直流穿墙套管交、直流试验电压下的局部放电量水平,验证其绝缘设计、材料选型、制造工艺的合理性,提出了低背景干扰的局部放电试验净空区域优化方法;利用电磁屏蔽试验空间内穿墙套管试验布置的有限元仿真模型计算了交流1 273 kV和直流+1 683 kV下的空间电场分布;通过测量接地尖端电极交流局部放电量、高电位均压环直流局部放电脉冲,得到了用于±1 100 kV直流穿墙套管交、直流局部放电试验净空区域优化的基准场强;通过对比净空区域优化前后局部放电背景干扰水平,验证了所采用的交、直流局部放电试验净空区域优化方法的正确性。研究结果可为有限电磁屏蔽试验大厅内特高压直流设备交、直流局部放电试验干扰信号识别和抑制提供方法和依据。

基于WAMS/SCADA混合量测的电力系统强跟踪滤波动态状态估计

针对当前电力系统动态状态估计主要采用的扩展卡尔曼滤波(EKF)法存在鲁棒性差、建模具有不确定性等缺点,提出一种强跟踪滤波动态状态估计算法。该算法在扩展卡尔曼滤波器中引入时变次优渐消因子,在线调整状态预报误差协方差矩阵和相应的增益矩阵,使状态估计残差方差最小。同时,引入广域测量系统(WAMS)/数据采集与监视控制(SCADA)系统的混合量测数据,增加了系统的冗余量测,进一步提高了动态状态估计的性能。仿真结果表明,所提方法在正常情况以及负荷突变、存在坏数据、网络拓扑错误各种情况下具有较好的预测和滤波效果。

改进的WPSS分段时延补偿方法

实现广域电力系统稳定器(WPSS)的工程应用的关键是对其反馈输入信号时延的良好补偿。对实际电网中相量测量单元(PMU)数据时延进行了实测,测试结果表明时延具有一定的随机分布特性和较强的抖动性。为适应时延的抖动特性,对分段时延补偿方法进行了改进,利用每次时延补偿器动作时刻前一段时间内的平均时延作为选择时延补偿的依据,避免了由于时延抖动带来的错误结果。在两区四机系统中进行的开环和闭环时频域仿真分析表明改进的方法能够更好地适应时延的变化,基于RTDS的实际电网仿真进一步验证了该方法在大系统中的有效性和可行性。

等离子随即引燃火炬技术在海上气田中的应用

海上气田通过对火炬系统进行改造,引入等离子随即引燃火炬技术,取得了良好的实践效果,大大提高了自动化水平。点火系统稳定可靠、操作简便,降低了火炬运行安全风险。同时,该火炬技术可以取消火炬长明灯和高低压吹扫气,实现火炬“零”燃料气消耗,践行“双碳”目标,筑牢安全环保屏障。等离子随即引燃火炬改造在海上气田属首次实施,改造效果显著,为其他油气田火炬放空气回收提供了借鉴,极具推广潜力,可为此类工作的开展提供有力的佐证。