基于用电信息采集系统台区线损治理提升典型经验

正为认真贯彻落实国网山东省电力公司关于建立协同联动机制切实解决台区线损管理问题的要求,规范台区线损管理,高密市供电公司成立了由纪委、组织部、营销部组成的联合行动小组,由营销部、各供电所线损专责组成的台区线损专项攻坚小组,开展"台区线损治理专项治理行动",全面查处在台区线损管理中的违规违纪行为,全面夯实营销基础管理,切实提升台区线损精益化管理水平,实     

加强营销管理 堵塞线损漏洞

线损工作贯穿于营销活动的全过程,加强营销管理,堵塞各种漏洞,对减少管理线损具有重要意义。在营销管理方面,我公司从以下几个方面入手,降低线损:1推行分台区线损管理考核办法各供电所实行了线损指标与职工效益工资和奖金挂钩的考核办法,公司把低压线损指标进行分解下达到各供电所,各供电所又根据实际情况,制定每个台区的具体线损     

“四个到位”强化线损管理

正国网河北武邑县供电公司全力开展线损专项整治工作,细化目标、落实责任,进一步规范台区线损核算工作和供用电秩序,采取"四个到位"狠抓工作落实,切实提升线损管理水平。1跟踪监测到位利用用电信息采集系统线损分析模块、营销系统线损管理模块和线损平台统计分析模块三套系统的相关特性,针对高、负损台区实时监测,做好台区考核表维护支撑,严把     

低压台区长期高损问题浅析

<正>台区线损异常分为三类情况,即高损情况、负损情况和其他情况,而高损台区占不合格台区比重达百分之七八十。国网河北石家庄供电分公司专项工作组针对配电网低压台区长期高损进行典型梳理,以治理为抓手,找出高损的原因,提出了相应的解决措施,提升了公司线损综合管理水平。1档案不一致问题1.1营销业务应用系统(SG 186)与现场台区户数关系     

台区同期线损管理的实践

<正>为贯彻落实公司营销工作部署,加强营销线损管理,巩固线损管理成效,推动供电所线损基础管理质量提升,国网河北任县供电公司经济开发区供电所完善线损管理组织和考核体系,通过加强线损过程管理和指标控制,使线损管理工作程序化、规范化、标准化。2019年上半年该所日均采集成功率为99.95%,台区线损合格率96.94%以上。1健全组织机构,明确考核办法该所以"线损管理示范县"创建活动为契机,成立     

岱湖供电所的降损之道

<正>线损管理作为供电企业的核心业务,已成为营销业绩考核的重要指标之一。为有效管控台区线损及台区实时线损指标,国网安徽萧县供电公司岱湖供电所因地制宜,分类施治,使得台区线损合格率显著提高。线损指标连续数月在县供电公司排名第一。1影响台区线损的原因分析该所对线损异常台区在前期进行全面摸底调查,经梳理分析认为,影响线损的因素主要表现在7个方面:一是台区三相负荷不平衡;二是树障影响;三是智     

智能电表条件下的台区线损管理

<正>肃宁县供电公司以台区线损为抓手,多渠道管控,多措施并举,使台区线损实现较大幅度降低,凸显了线损管理成效。发挥线损管理机制作用,强化管理降损举措完善线损管理体制。为加强对线损管理工作的组织领导,2016年初,肃宁县供电公司成立了以公司主要领导为组长,主管领导为副组长,发建、运检、营销、调控等部门负责人及各供电所所长为成员的线损领导小组,明确了各职能部室在线损管理中的具体职责。     

常抓不懈 细致管理 实现台区全面降损

正台区线损率直接影响企业的整体效益。乡镇供电所作为电力企业管理最末端,台区线损的管理水平直接关系到整个公司的运行情况,加强人员管理是提升基层线损管理水平的关键环节。目前乡镇供电所的管理已经逐渐从以前的农电综合管理过渡为专业部门专业化管理,考核体系、管理机制日趋完善,其中线损管理由各级营销部门直接牵头。供电所全面完成台区经理网格化管理,营配末端融合。     

基于大数据分析 提高台区线损异常诊断

正随着智能电网建设工作的不断深入、智能电能表的全覆盖以及用电信息采集系统、营销业务应用系统和设备(资产)运维精益管理系统的广泛应用,目前全国各地各级供电企业基本已经完成智能集抄系统建设工作。而随着全采集全覆盖项目的实施,深化数据的互联互通,通过科学的分析,能有效帮助台区经理快速排查、准确定位,为解决异常线损提供辅助决策,减少人力资源的浪费,提高台区线损精益化管理水平。     

加强线损综合治理的做法

正为有效治理高线损台区,国网河北灵寿县供电公司以问题为导向,逐台分析摸排重点,深入查找薄弱环节和管理短板,深化、细化各项治理措施,力求从源头上堵塞漏洞降线损。现将该公司加强线损综合治理的做法简述如下。(1)为确保线损综合治理工作取得实效,坚持"一把手"负总责,主要领导亲自抓,营销、供电所等相关部     

Relationship between stable carbon isotope discrimination and water use efficiency under regulated deficit irrigation of pear-jujube tree

To investigate the relationship between stable carbon isotope discrimination (Δ) of different organs and water use efficiency (WUE) under different water deficit levels, severe, moderate and low water deficit levels were treated at bud burst to leafing, flowering to fruit set, fruit growth and fruit maturation stages of field grown pear-jujube tree, and leaf stable carbon isotope discrimination (Δ_L) at different growth stages and fruit stable carbon isotope discrimination (Δ_F) at fruit maturation stage were measured. The results indicated that water deficit had significant effect on Δ_L at different growth stages and Δ_F at fruit maturation stage. As compared with full irrigation, the average Δ_L at different growth stages and Δ_F at fruit maturation stage were decreased by 1.23% and 2.67% for different water deficit levels, respectively. Δ_L and Δ_F among different water deficit treatments had significant difference at the same growth stage (P < 0.05). Under different water deficit conditions, significant relationships between the Δ_L and WUE_i (photosynthesis rate/transpiration rate, P_n/T_r), WUE_n (photosynthesis rate/stomatal conductance of CO_2, P_n/g_s), WUE_y (yield/crop water consumption, Y/ET_c) and yield, or between the Δ_F and WUE_y and yield were found, respectively. There were significantly negative correlations of Δ_L with WUE_i, WUE_n, WUE_y and yield (P < 0.01) at the fruit maturation stage, or Δ_L with WUE_i and WUE_n (P < 0.01) over whole growth stage, respectively. Δ_F was negatively correlated with WUE_y, WUE_n and yield (P < 0.05), but positively correlated with ET_c (P < 0.01) over the whole growth stage. Thus Δ_L or Δ_F can compare WUE_n and WUE_y, so the stable carbon isotope discrimination method can be applied to evaluate the water use efficiency of pear-jujube tree under the regulated deficit irrigation.     

Root biomass, crop response and water-yield relationship of mustard (Brassica juncea L.) grown under combinations of irrigation and nutrient application

A 3-year study was carried out to assess the root biomass production, crop growth rate, yield attributes, canopy temperature and water-yield relationships in Indian mustard grown under combinations of irrigation and nutrient application for revealing the dynamic relationship of crop yield (Y) and seasonal evapotranspiration (ET). Three post-sowing irrigation treatments viz. no irrigation (I ₁), one irrigation at flowering (I ₂) and two irrigations one each at rosette and flowering stage (I ₃), three nutrient treatments viz. no fertilizer or manure (F ₁), 100% recommended NPK i.e., 60 kg N, 13.1 kg P and 16.6 kg K ha⁻¹ (F ₂) and 100% recommended NPK plus farmyard manure @ 10 Mg ha⁻¹ (F ₃) were tested in a split-plot design. Root biomass was significantly greater in I ₃ than I ₂ and I ₁, and in F ₃ than F ₂ and F ₁. The I ₃ × F ₃, I ₂ × F ₃ and I ₃ × F ₂ combinations maintained significantly greater crop growth rate, plant height, yield components, ET and crop yield and better plant water status in terms of canopy temperature, canopy-air temperature difference (CATD) and relative leaf water content (RLWC). Number of siliqua plant⁻¹ and seeds siliqua⁻¹ were the major contributors to the seed yield. Marginal analysis of water production function was used to establish Y–ET relationship. The elasticity of water production (E _wp) provides a means to assess relative changes in Y and ET, and gives an indication of improvement of Y due to nutrient application. The ET–Y relationships were linear with marginal water use efficiency (WUE_m) of 3.09, 4.23 and 3.95 kg ha⁻¹ mm⁻¹ in F ₁, F ₂ and F ₃, respectively, and the corresponding E _wp were 0.63, 0.71 and 0.61. This implies that the scope for improving yield and WUE with 100% NPK was little compared with 100% NPK + farmyard manure. The crop yield was highest in I ₃ × F ₃ combination, and the similar yield was obtained in I ₂ × F ₃ and I ₃ × F ₂ combinations. Application of organic manure along with 100% NPK fertilizers maintained greater crop growth rate, better water relation in plants, yield attributes and saved one post-sowing irrigation.     

Midday measurements of leaf water potential and stomatal conductance are highly correlated with daily water use of Thompson Seedless grapevines

A study was conducted to determine the relationship between midday measurements of vine water status and daily water use of grapevines measured with a weighing lysimeter. Water applications to the vines were terminated on August 24th for 9 days and again on September 14th for 22 days. Daily water use of the vines in the lysimeter (ET_LYS) was approximately 40 L vine⁻¹ (5.3 mm) prior to turning the pump off, and it decreased to 22.3 L vine⁻¹ by September 2nd. Pre-dawn leaf water potential (Ψ_PD) and midday Ψ_l on August 24th were −0.075 and −0.76 MPa, respectively, with midday Ψ_l decreasing to −1.28 MPa on September 2nd. Leaf g _s decreased from ~500 to ~200 mmol m⁻² s⁻¹ during the two dry-down periods. Midday measurements of g _s and Ψ_l were significantly correlated with one another (r = 0.96) and both with ET_LYS/ET_o (r = ~0.9). The decreases in Ψ_l, g _s, and ET_LYS/ET_o in this study were also a linear function of the decrease in volumetric soil water content. The results indicate that even modest water stress can greatly reduce grapevine water use and that short-term measures of vine water status taken at midday are a reflection of daily grapevine water use.     

A preliminary study of an alternative controlled drainage strategy in surface drainage ditches: Low-grade weirs

This study examined hydrological characteristics of low-grade weirs, an alternative controlled drainage strategy in surface drainage ditches. Chemographs of vegetated and clear scraped (control) replicates of weir vs. non-weir treatments were compared to determine differences in time to peak (T_p) and time to base (T_b). Drainage ditches T_p and T_b were affected by both vegetation and weir presence. The order of treatment efficiency for T_p was observed to be: non-vegetated non-weir < vegetated non-weir < non-vegetated weir < vegetated weir. Furthermore, T_b for each ditch was the reverse relationship from T_p where vegetated weir > non-vegetated weir > vegetated non-weir > non-vegetated non-weir. Low-grade weirs increase chemical retention time (vegetated and clear scraped), the average time a molecule of contaminant remains in the system. Future research in water quality improvement and weir management will yield useful information for non-point source pollutant reduction.     

Water production functions of wheat (Triticum aestivum L.) irrigated with saline and alkali waters using double-line source sprinkler system

Expected yield losses as a function of quality and quantity of water applied for irrigation are required to formulate guidelines for the effective utilisation of marginal quality waters. In an experiment conducted during 2004-2006, double-line source sprinklers were used to determine the separate and interactive effects of saline and alkali irrigation waters on wheat (Triticum aestivum L.). The study included three water qualities: groundwater (GW; electrical conductivity of water, ECw 3.5 dS m⁻¹; sodium adsorption ratio, SAR 9.8 mmol L⁻¹; residual sodium carbonate, RSC, nil) available at the site, and two synthesized waters, saline (SW; ECw 9.4 dS m⁻¹, SAR 10.3 mmol L⁻¹; RSC nil) and alkali (AW; ECw 3.7 dS m⁻¹, SAR 15.1 mmol L⁻¹; RSC 9.6 meq. L⁻¹). The depths of applied SW, AW, and GW per irrigation ranged from 0.7 to 3.5 cm; the depths of applied mixtures of GW with either SW (MSW) or AW (MAW) ranged from 3.2 to 5 cm. Thereby, the water applied for post-plant irrigations using either of GW, SW or AW ranged between 15.2 and 34.6 cm and 17.1 and 48.1 cm during 2004-2005 and 2005-2006, respectively and the range was 32.1-37.0 and 53.1-60.0 cm for MSW or MAW. Grain yields, when averaged for two years, ranged between 3.08 and 4.36 Mg ha⁻¹, 2.57 and 3.70 Mg ha⁻¹ and 2.73 and 3.74 Mg ha⁻¹ with various quantities of water applied using GW, SW and AW, respectively, and between 3.47 and 3.75 Mg ha⁻¹ and 3.63 and 3.77 Mg ha⁻¹ for MSW and MAW, respectively. The water production functions developed for the two sets of water quality treatments could be represented as: RY = 0.528 + 0.843(WA/OPE) − 0.359(WA/OPE)² − 0.027ECw + 0.44 × 10⁻²(WA/OPE) × ECw for SW (R² = 0.63); RY = 0.446 + 0.816(OPE/WA) − 0.326(WA/OPE)² − 0.0124RSC − 0.55 × 10⁻⁴(WA/OPE) × RSC for AW (R² = 0.56). Here, RY, WA and OPE are the relative yields in reference to the maximum yield obtained with GW, water applied for pre- and post-plant irrigations (cm), and open pan evaporation, respectively. Crop yield increased with increasing amount of applied water for all of the irrigation waters but the maximum yields as obtained with GW, could not be attained even with increased quantities of SW and AW. Increased frequency of irrigation with sprinklers reduced the rate of yield decline with increasing salinity in irrigation water. The sodium contents of plants increased with salinity/alkalinity of sprinkled waters as also with their quantities. Simultaneous decrease in potassium contents resulted in remarkable increase in Na:K ratio.     

Evapotranspiration and crop coefficient of Populus euphratica Oliv forest during the growing season in the extreme arid region northwest China

Based on successive observation, fifteen-day evapotranspiration (ET_c) of Populus euphratica Oliv forest, in the extreme arid region northwest China, was estimated by application of Bowen ratio-energy balance method (BREB) during the growing season in 2005. During the growing season in 2005, total ET_c was 446.96 mm. From the beginning of growing season, the ET_c increased gradually, and reached its maximum value of 6.724 mm d⁻¹ in the last fifteen days of June. Hereafter the ET_c dropped rapidly, and reached its minimum value of 1.215 mm d⁻¹ at the end of growing season. The variation pattern of crop coefficient (K_c) was similar to that of ET_c. From the beginning of growing season, the K_c value increased rapidly, and reached its maximum value of 0.623 in the last fifteen days of June. Afterward, with slowing growth of P. euphratica, the value dropped rapidly to the end of growing season. According to this study, the ET_c of P. euphratica forest is affected not only by meteorological factors, but by water content in soil.     

Impacts of climate variability on reference evapotranspiration over 58 years in the Haihe river basin of north China

Physically, evaporative demand is driven by net radiation (R_n), vapour pressure (e_a), wind speed (u₂), and air temperature (T_a), each of which changes over time. By analyzing temporal variations in reference evapotranspiration (ET₀), improved understanding of the impacts of climate change on hydrological processes can be obtained. In this study, variations in ET₀ over 58 years (1950-2007) at 34 stations in the Haihe river basin of China were analyzed. ET₀ was calculated by the FAO Penman-Monteith formula. Calculation of Kendall rank coefficient was done by analyzing the annual and seasonal trends in ET₀ derived from its dependent climate variables. Inverse distance weighting (IDW) was used to analyze the spatial variation in annual and seasonal ET₀, and in each climate variable. An attribution analysis was performed to quantify the contribution of each input variable to ET₀ variation. The results showed that ET₀ gradually decreased in the whole basin over the 58 years at a rate of −1.0 mm yr⁻², at the same time, R_n, u₂ and precipitation also decreased. Changes in ET₀ were attributed to the variations in net radiation (−0.9 mm yr⁻²), vapour pressure (−0.5 mm yr⁻²), wind speed (−1.3 mm yr⁻²) and air temperature (1.7 mm yr⁻²). Looking at all data on a month by month basis, we found that T_a had a positive effect on dET₀/dt (the derivative of reference evapotranspiration to time) and R_n and u₂ had negative effects on dET₀/dt. While changes in air temperature were found to produce a large increase in dET₀/dt, changes in other key variables each reduced rates, resulting in an overall negative trend in dET₀/dt.     

Increasing water productivity of irrigated crops under limited water supply at field scale

Borkhar district is located in an arid to semi-arid region in Iran and regularly faces widespread drought. Given current water scarcity, the limited available water should be used as efficient and productive as possible. To explore on-farm strategies which result in higher economic gains and water productivity (WP), a physically based agrohydrological model, Soil Water Atmosphere Plant (SWAP), was calibrated and validated using intensive measured data at eight selected farmer fields (wheat, fodder maize, sunflower and sugar beet) in the Borkhar district, Iran during the agricultural year 2004-2005. The WP values for the main crops were computed using the SWAP simulated water balance components, i.e. transpiration T, evapotranspiration ET, irrigation I, and the marketable yield Y_M in terms in terms of Y_MT⁻¹, Y_M ET⁻¹ and Y_M I⁻¹.The average WP, expressed as $ T⁻¹ (US $ m⁻³) was 0.19 for wheat, 0.5 for fodder maize, 0.06 for sunflower and 0.38 for sugar beet. This indicated that fodder maize provides the highest economic benefit in the Borkhar irrigation district. Soil evaporation caused the average WP values, expressed as Y_M ET⁻¹ (kg m⁻³), to be significantly lower than the average WP, expressed as Y_MT⁻¹, i.e. about 27% for wheat, 11% for fodder maize, 12% for sunflower and 0.18 for sugar beet. Furthermore, due to percolation from root zone and stored moisture content in the root zone, the average WP values, expressed as Y_MI⁻¹ (kg m⁻³), had a 24-42% reduction as compared with WP, expressed as Y_M ET⁻¹.The results indicated that during the limited water supply period, on-farm strategies like deficit irrigation scheduling and reduction of the cultivated area can result in higher economic gains. Improved irrigation practices in terms of irrigation timing and amount, increased WP in terms of Y_MI⁻¹ (kg m⁻³) by a factor of 1.5 for wheat and maize, 1.3 for sunflower and 1.1 for sugar beet. Under water shortage conditions, reduction of the cultivated area yielded higher water productivity values as compared to deficit irrigation.     

Soil salinity related to physical soil characteristics and irrigation management in four Mediterranean irrigation districts

Irrigated agriculture is threatened by soil salinity in numerous arid and semiarid areas of the Mediterranean basin. The objective of this work was to quantify soil salinity through electromagnetic induction (EMI) techniques and relate it to the physical characteristics and irrigation management of four Mediterranean irrigation districts located in Morocco, Spain, Tunisia and Turkey. The volume and salinity of the main water inputs (irrigation and precipitation) and outputs (crop evapotranspiration and drainage) were measured or estimated in each district. Soil salinity (EC_e) maps were obtained through electromagnetic induction surveys (EC_a readings) and district-specific EC_a-EC_e calibrations. Gravimetric soil water content (WC) and soil saturation percentage (SP) were also measured in the soil calibration samples. The EC_a-EC_e calibration equations were highly significant (P < 0.001) in all districts. EC_a was not significantly correlated (P > 0.1) with WC, and was only significantly correlated (P < 0.1) with soil texture (estimated by SP) in Spain. Hence, EC_a mainly depended upon EC_e, so that the maps developed could be used effectively to assess soil salinity and its spatial variability. The surface-weighted average EC_e values were low to moderate, and ranked the districts in the order: Tunisia (3.4 dS m⁻¹) > Morocco (2.2 dS m⁻¹) > Spain (1.4 dS m⁻¹) > Turkey (0.45 dS m⁻¹). Soil salinity was mainly affected by irrigation water salinity and irrigation efficiency. Drainage water salinity at the exit of each district was mostly affected by soil salinity and irrigation efficiency, with values very high in Tunisia (9.0 dS m⁻¹), high in Spain (4.6 dS m⁻¹), moderate in Morocco (estimated at 2.6 dS m⁻¹), and low in Turkey (1.4 dS m⁻¹). Salt loads in drainage waters, calculated from their salinity (EC_dw) and volume (Q), were highest in Tunisia (very high Q and very high EC_dw), intermediate in Turkey (extremely high Q and low EC_dw) and lowest in Spain (very low Q and high EC_dw) (there were no Q data for Morocco). Reduction of these high drainage volumes through sound irrigation management would be the most efficient way to control the off-site salt-pollution caused by these Mediterranean irrigation districts.     

Irrigation rate and plant density effects on yield and water use efficiency of drip-irrigated corn

The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. This study was conducted for 2 years (2005 and 2006) to establish optimal irrigation rates and plant population densities for corn (Zea mays L.) in sandy soils using drip irrigation system. The study aimed at achieving high yield and efficient irrigation water use (IWUE) simultaneously. A field experiment was conducted using a randomized complete block split plot design with three drip irrigation rates (I₁: 1.00, I₂: 0.80, and I₃: 0.60 of the estimated evapotranspiration), and three plant population densities (D₁: 48,000, D₂: 71,000 and D₃: 95,000 plants ha⁻¹) as the main plot and split plot, respectively. Irrigation water applied at I₁, I₂ and I₃ were 5955, 4762 and 3572 m³ ha⁻¹, respectively. A 3-day irrigation interval and three-way cross 310 hybrid corn were used. Results indicated that corn yield, yield components, and IWUE increased with increasing irrigation rates and decreasing plant population densities. Significant interaction effects between irrigation rate and plant population density were detected in both seasons for yield, selected yield components, and IWUE. The highest grain yield, yield components, and IWUE were found for I₁D₁, I₁D₂, or I₂D_1, while the lowest were found for I₃D₂ or I₃D₃. Thus, a high irrigation rate with low or medium plant population densities or a medium irrigation rate with a low plant population density are recommended for drip-irrigated corn in sandy soil. Crop production functions with respect to irrigation rates, determined for grain yield and different yield components, enable the results from this study to be extrapolated to similar agro-climatic conditions.