Clusteranalyse von Smart-Meter-Daten

The introduction of smart meter technology is a great challenge for the German energy industry. It requires not only large investments in the communication and metering infrastructure, but also a redesign of traditional business processes. The newly incurring costs cannot be fully passed on to the end customers. One option to counterbalance these expenses is to exploit the newly generated smart metering data for the creation of new services and improved processes. For instance, performing a cluster analysis of smart metering data focused on the customers?? time-based consumption behavior allows for a detailed customer segmentation. In the article we present a cluster analysis performed on real-world consumption data from a smart meter project conducted by a German regional utilities company. We show how to integrate a cluster analysis approach into a business intelligence environment and evaluate this artifact as defined by design science. We discuss the results of the cluster analysis and highlight options to apply them to segment-specific tariff design.     

NB-IoT燃气表节能和气量告警方法设计

近年来,窄带物联网(NB-IoT)技术的出现推动了相关设备的发展,基于NB-IoT的新型智能燃气表将被逐步推广开来。然而现有的计费方式只是简单的利用表内计算模块,会出现意外断气的情况。为了很大程度上避免由于余额不足导致燃气表关阀从而造成的使用延迟,提升用户的使用体验,同时也满足对NB-IoT智能燃气计费表的低功耗要求,面向预付费模式设计了一种节能和气量告警处理方法。该方法通过减少NB-IoT智能燃气表的同步请求发起次数以及多阈值设置进行用户警报提醒。仿真结果表明,上述方法可以在合理的时间对用户作出余额的提醒从而切实保证用户的使用体验,同时达到进一步降低燃气表能耗的目标。     

基于WirelessHART的电力无线传感网设计

为推动泛在电力物联网建设,提高感知层电力数据采集量,解决传统电力系统有线电表布线成本大、恶劣环境下施工不便及人工抄表效率差等问题,设计了一种基于WirelessHART协议的无线智能电表,建立节点路由算法与时间同步算法,使多台智能电表构成完整的电力无线传感网络,对电能实现实时可靠的电力计量与调度。将无线网关在上位机进行测试,判断网络的传输效率与稳定性。     

基于71M6543G的三相智能电表实现

针对我国智能电网的发展趋势和需求,介绍一种以71M6543G为核心的三相智能电表的设计方案。详细介绍了智能电表关键硬件部分以及软件部分的实现。设计采用MAXIM公司生产的第四代多相电表片上系统(SoC)71M6543G,实际使用表明,该电表设计抗干扰能力强,精度高,符合当前市场对智能电表的实际需求。     

射频卡智能水表系统的设计

给出了一种基于超低功耗芯片MSP430F149单片机的射频卡智能水表系统的设计方案,其中采用射频卡T5557及其读写基站U2270B作为系统的射频读写模块。重点阐述了系统的硬件构成及软件设计流程,并简单介绍了基于此系统的用水管理系统的设计。该射频卡智能水表可广泛应用于各城市供水系统,并可作进一步推广应用到工业用液体如石油,化工等流量计量计费系统。     

A survey on cyber attacks against nonlinear state estimation in power systems of ubiquitous cities

It is well-known that critical infrastructures would be targets for cyber attacks. In this paper, we focus on the power systems (i.e. smart grids) in ubiquitous cities, where every meter is linked to an information network through wireless networking. In a smart grid system, information from smart meters would be used to perform a state estimation in real time to maintain the stability of the system. A wrong estimation may lead to disastrous consequences (e.g. suspension of electricity supply or a big financial loss). Unfortunately, quite a number of recent results showed that attacks on this estimation process are feasible by manipulating readings of only a few meters. In this paper, we focus on nonlinear state estimation which is a more realistic model and widely employed in a real power grid environment. We category cyber attacks against nonlinear state estimation, and review the mechanisms behind. State-of-the-art security measures to detect these attacks are discussed via sensor protection. Hope that the community would be able to come up with a secure system architecture for ubiquitous cities.     

Distributed algorithms for QoS load balancing

We consider a dynamic load balancing scenario in which users allocate resources in a non-cooperative and selfish fashion. The perceived performance of a resource for a user decreases with the number of users that allocate the resource. In our dynamic, concurrent model, users may reallocate resources in a round-based fashion. As opposed to various settings analyzed in the literature, we assume that users have quality of service demands. A user has zero utility when falling short of a certain minimum performance threshold and having positive utility otherwise. Whereas various load-balancing protocols have been proposed for the setting without quality of service requirements, we consider protocols that satisfy an additional locality constraint: The behavior of a user depends merely on the state of the resource it currently allocates. This property is particularly useful in scenarios where the state of other resources is not readily accessible. For instance, if resources represent channels in a mobile network, then accessing channel information may require time-intensive measurements. We consider several variants of the model, where the quality of service demands may depend on the user, the resource, or both. For all cases we present protocols for which the dynamics converge to a state in which all users are satisfied. More importantly, the time to reach such a state scales nicely. It is only logarithmic in the number of users, which makes our protocols applicable in large-scale systems.     

The prediction of network efficiency in the smart grid

AMI is the core infrastructure of a smart grid and it is expected to be used for many industrial fields. The components of AMI generally include a smart meter, DCU, and MDMS. In such a system, the smart meter measures power consumption and DCU collects information from smart meters and send their data to MDMS. The MDMS is an end server to get information of the power usage and store its log and data. Since there are a lot of devices such as smart meters and DCUs in AMI, it is important to maintain the suitable number of them. In particular, it is necessary to calculate the proper number of DCUs for efficient management of AMI. In this paper, we suggest a way to predict the proper number of DCUs and this proposed method is useful to predict the total performance of heterogeneous AMI. The simulation results show that AMI is greatly influenced by the difference of performance between DCUs in the heterogeneous AMI.     

智能电网中的智能抄表技术分析

抄表系统的智能化发展已成为一种趋势,智能抄表系统具有节约成本,高效管理,抄表精确,方便用户等优点,在智能电网中有着重要的意义.本文介绍了智能电网中智能抄表的意义,列举了现有的智能抄表技术,然后对智能抄表的新热点进行了探讨,并设计实现了基于Zigbee的抄表系统,给出了系统组成及工作原理和系统软件设计过程,说明了该系统的实用性和优越性,最后对全文进行了总结.     

基于误差在线自诊断技术的智能电表设计

随着坚强智能电网的建设,电能表的现场检验技术滞后于电网发展,造成大量的资源浪费。对误差在线自诊断技术进行了研究。基于ADE9153计量芯片的mSure技术,设计一款具有在线误差自诊断功能的智能电能表。对电能表的软件和硬件作了设计改进。通过分析电能表采样电路的性能改变,监测电能表因窃电、计量故障、器件老化或失效引起的误差改变。通过远程数据采集实现对电能表生命周期内的误差在线监测,便于故障及时发现、精准定位。基于大数据分析,为供电部门合理规划、有序轮换电能表提供参考依据,延长了电能表的使用寿命、减少了资源浪费。通过试验室测试及现场运行测试,验证了误差在线自诊断技术的准确性、稳定性、可靠性。     

智能电网AMI网络隐私保护的读数采集策略

提出一种网络隐私保护的读数采集策略.本策略在智能电表中采集读数加入掩码,并将所有的智能电表读数进行聚合并消除所有的掩码才能得到真实的电能消费信息,因此单单获取一个智能电表的读数无法得到真实的电能消费读数.每个智能电表和其他电表或电网设施之间通过一个代理分享其自身的掩码信息.NS-3仿真实验结果表明,本文的策略优于其他现有的方案.     

基于反汇编的智能电表软件功能检测模型

电力企业在智能电表的生产过程中发现制造商用于招标展示的样品表和竞标成功后大量投产的批量表存在显著差异。由于检测不足,许多投入实际使用的批量表出现工作状态异常、质量不合格的情况,对这些电表的维护造成了不必要的花费。针对此问题制定了一种智能电表软件功能检测方案,设计了一种嵌入式智能电表代码逆向模型。模型以分析智能电表核心程序从而获取系统运行特征为思路,以反汇编算法分析电表固件代码功能为手段,对嵌入式智能电表进行软件功能差异测试。模型包括固件代码提取、固件代码反汇编和软件功能比较三大模块,在反汇编模块中基于现有的线性扫描和递归遍历算法使用了一种改进的单步扫描算法(SDA)。实际应用时对智能电表批量产品和样品进行比较鉴别,对系统功能的差异测量效果明显;同时使用该模型在维护电力企业已使用电表时可控制拟投产电表与已使用电表功能和质量误差在±20%范围内。     

Gridchain: an investigation of privacy for the future local distribution grid

As part of building the smart grid, there is a massive deployment of so-called smart meters that aggregate information and communicate with the back-end office, apart from measuring properties of the local network. Detailed measurements and communication of, e.g., consumption allows for remote billing, but also in finding problems in the distribution of power and overall to provide data to be used to plan future upgrades of the network. From a security perspective, a massive deployment of such Internet of Things (IoT) components increases the risk that some may be compromised or that collected data are used for privacy-sensitive inference of the consumption of households. In this paper, we investigate the privacy concerns regarding detailed readings of smart meters for billing purposes. We present Gridchain, a solution where households can opt-in to hide their consumption patterns and thus make Non-Intrusive Load Monitoring (NILM) more challenging. Households form groups where they can trade real consumption among themselves to achieve reported consumption that would be resistant to NILM. Gridchain is built on a publish/subscribe model and uses a permissioned blockchain to record any trades, meaning that dishonest households can be discovered and punished if they steal from other households in the group or the electricity company in the end. We implement and release a proof of concept of Gridchain and use public datasets to allow reproducibility. Our results show that even if an attacker has access to the reported electricity consumption of any member of a Gridchain group, this reported consumption is significantly far from the actual consumption to allow for a detailed fingerprint of the household activities.

     

Privacy-enhanced architecture for smart metering

The recent deployment of smart grids promises to bring numerous advantages in terms of energy consumption reduction in both homes and businesses. A more transparent and instantaneous measurement of electricity consumption through smart meters utilization leads to an enhancement in the ability of monitoring, controlling and predicting energy usage. Nevertheless, it also has associated drawbacks related to the privacy of customers, since such management might reveal their personal habits, which electrical appliances they are using at each moment, whether they are at home or not, etc. In this work, we present a privacy-enhanced architecture for smart metering aimed at tackling this threat by means of encrypting individual measurements while allowing the electricity supplier to access the aggregation of the corresponding decrypted values.     

Implications of customer value perceptions for the design of electricity efficiency services in times of smart metering

Smart meters are the backbone of modern electricity metering and an important enabler of reaching energy efficiency targets. The implementation of new metering infrastructure is, however, making little progress and is often focused on technical aspects only. Additionally, existing smart metering information systems do not yet exploit the possibilities to optimally support customers in their electricity savings activities. Knowing customer preferences is absolutely essential for the effectiveness of energy efficiency measures and, as a consequence, for realizing the economic value of smart metering technology. The presented research contributes to the field by identifying customer value perceptions concerning new smart meter services in the retail electricity market in Switzerland. Founded on a choice-based conjoint analysis with a data sample of more than 1500 respondents from three Swiss regions, five customer segments with different preferences are identified. With the exception of the comfort-oriented customer segment, the other four segments are comprised of customers who are willing (1) to pay for smart meter services and (2) to change their behavior to save electricity. Based on the identified customer value perceptions, implications for the design of smart meter-based energy efficiency services are elaborated.     

多网融合下异构分层的智能化供水系统研究

在多网融合的过程中,网络和服务覆盖的范围向更多的行业延伸。探讨供水行业的智能化供水系统,特别是系统的网络架构、远程预付费、IC卡预付费、自动抄表功能的设计。针对目前用水计量与信息环境的复杂特点,提出在多网融合环境下按异构分层模式来构建系统。该系统采用多线程的集中轮询异步模式实现智能水表远程预付费功能,应用虚拟串口技术解决分布式远程设备控制以实现 IC 卡表预付费功能,具有可调时间的自动抄表及水费自动结算、水损分析等功能,应用表明了该系统的有效性与适用性。     

基于VAR的电能表降维误差估计模型

为达到远程监控电能表状态并及时准确发现电能表异常的目的,本文提出了一种基于VAR的电能表降维误差估计模型,通过对于电能表电量数据的获取、分析及筛选,采用主成分分析方法（PCA）对于原始数据进行降维,通过向量自回归模型（VAR）提取时间序列中的特征,从而准确预测电能表使用电量并对比出用电异常电能表。其中PCA降维算法处理了实际模型的不可解性,VAR自回归算法提高了估计的稳定性和精度,相较于传统方法具有预测准确度高,所需数据量小的特点。为验证该方法的有效性和实用性,将该方法应用于实际台区中测试,通过对于台区中127块电表半年内的用电数据进行分析,准确定位出8个异常电能表。结果表明,该方法不需要提前独立计算网损,能够实时估计智能电表误差和网损率。     

A novel data collection mechanism for smart grids using public transportation buses

In this study, we propose a novel solution for collecting smart meter data by merging Vehicular Ad-Hoc Networks (VANET) and smart grid communication technologies. In our proposed mechanism, Vehicular Ad-Hoc Networks are utilized for collecting data from smart meters, eliminating the need for manpower. To the best of our knowledge, this is the first study proposing the utilization of public transportation vehicles for collecting data from smart meters. With this work, the use of the IEEE 802.11p protocol has been proposed for the first time for use in smart grid applications. In our scheme, data flows first from smart meters to a bus through infrastructure-to-vehicle (I2V) communication and then from the bus to a bus stop through vehicle-to-infrastructure (V2I) communication. The performance of our proposed mechanism has been investigated in detail in terms of end-to-end delay and delivery ratio by using Network Simulator-2 and with different routing protocols.     

基于DSP的多路抄表系统的设计与实现

分析了目前抄表系统中存在的一些问题,提出了一种基于DSP的多路水表号码识别系统,给出了系统的设计方案及各功能模块实现过程。系统属于无源远程抄表方式,采用嵌入式技术和视觉检测技术,通过对水表号码图片的采集及识别处理,实现对多路水表读数的显示及传输。实验证明该系统成本低、速度快、安全、节能、工作稳定,可以准确识别水表读数。     

基于B／／s模式的智能用电服务系统设计与开发

针对智能电网下智能终端的应用,结合现有量测方法和计算机网络技术,提出了一种基于B／S模式的智能用电服务系统的实现方案。该系统以智能电表的应用为硬件基础,通过网络协议编程构建用电自动测量网络,并实现对用户用电数据的实时采集。软件则以2LAMP（Linux＋Apache＋MySQL＋PHP）为开发平台,综合利用AJAX（异步JavaScript和xML,AsynchronousJavaScriptandXML）以及实时数据库技术实现系统的整体设计。该用电智能服务系统以浏览器为用户终端,可以为用户提供综合耗电统计、在线用电付费、智能用电决策以及实时信息交流等便捷而多样化的服务入口,从而为实现用户智能用电提供有力支撑。