The state of advanced measurement and verification technology and industry application

With the expansion of advanced metering and increased use of energy analytics tools, the energy efficiency community has begun to explore the application of advanced measurement and verification (or ‘M&V 2.0′) technologies. Current literature recognizes their promise, but does not offer in-depth assessment of technical underpinnings. This paper assesses the state of the technology and its application. Sixteen commercially available technologies were characterized and combined with a national review of their use.     

电网升压改造节能量测量与验证计算模型与方法

为了提高电网输送容量和电压等级的标准化,升压改造是电网企业的一项重要的技改措施。根据国家标准《GB/T 28750-2012S节能量测量和验证技术通则》关于节能量计算的基本原理,结合电网建设运行的实际情况,本文提出了一种电网升压改造节能量测量与验证的计算模型和方法,能够准确充分地体现电网升压改造所产生的节能环保效益。     

Dispatch of Direct Load Control for Fuel Cost Minimization

The concept, algorithm and the requisite mathematics for the dispatch of Direct Load Control (DLC) for fuel cost-minimization is developed. The dispatch decision is based on the consideration of producing fuel cost savings. The dispatch is integrated with the economic dispatch of conventional generation. The algorithm for the dispatch and coordination of DLC takes into account all operational constraints on the dispatch of DLC. A method is thus provided for rendering the DLC program flexible to changing system requirements. DLC can be integrated into system operations and utilized for peak shaving and/or fuel cost savings, as and when required.     

Classification of direct load control curves for performance evaluation

In evaluating the performance of direct load control (DLC) programs, an essential task is to classify the DLC curves into either the one complying with the program or not. This paper presents an efficient approach to clustering the DLC curves through a structure of self-organizing maps (SOM). Aiming at selecting significant features of DLC curves, methods of nonlinear principal component analysis (NLPCA) and periodic analysis are proposed for feature extraction. The dual multilayer neural networks (DMNN) model is employed in the proposed NLPCA method. In the periodic analysis method, the periodic characteristics of the DLC curves are investigated. In the SOM, Davies-Bouldin (DB) indexes and a k-means algorithm decide the best number of clusters to be classified. Through the proposed methods, the DLC curves are thus divided into the two categories by the SOM: DLC complying and DLC noncomplying loads. Results obtained from the comparison of six different approaches show that the clusters obtained from the proposed approach exhibit lowest degrees of misclassification for the practical data on Taiwan Power Company (TPC) DLC programs.     

PJM日前市场电价的统计分析

对市场电价的统计分析有助于掌握电价的分布规律,并为发电厂投资、市场风险评估等研究提供依据。文中基于美国PJM（Pennsylvania—New Jersey—Mary land）日前市场的实际数据,采用K-S（Kolmogorov—Smirnove）检验法对电价的统计性质进行了验证,得出如下结论：首先,PJM日前市场的年电价服从对数正态分布;其次,以负荷高低水平将电价进行分类,在中高等负荷时段,电价服从对数正态分布,而低负荷时段电价服从正态分布;最后,在不同负荷的情形下,负荷与其对应电价的均值、标准差之间存在着一种近似的线性关系。     

Measuring persistence of energy savings after COVID-19

Publicly funded energy efficiency projects require measurement to inform climate and energy policy, craft program budgets, and determine the cost-benefit ratios of different projects. One of the key inputs into cost-benefit analyses is the concept of an effective useful life, or EUL. This value, typically measured in years, lets programs and policy makers estimate how many years the energy savings will last. For most programs, this measurement is done based on manufacturing assumptions, i.e. the laboratory determined that an LED lightbulb would last for 10,000 h, or 15 years. New programs, using a methodology known as “advanced measurement and verification (AM&V)” measure the EUL using a survival analysis of the savings. We ask the question, “At what point will this project be savings less than 50% of what it saved on day 1.” We measure the energy consumption of a facility at the meter level to determine how much energy is being used compared to when the measure was installed. COVID-19 has thrown a wrench in the ability to compare energy use across years. Not only is there a disruption from COVID-19 directly, but entire industries have fundamentally changed the way that they operate their buildings and run their businesses. We are able to extract out the impacts of COVID for many of our building’s models, but not all. Using methods derived from independent, third-party evaluators, we have developed a new way to measure the ongoing persistence of energy savings using self-report data from participants at the project level, rather than at the savings level. Doing this will allow us to compare the data from pre-COVID with the new world full of post-COVID data, and to assess the true impacts of COVID on the energy efficiency industry’s most basic cost-effectiveness assumptions.     

基于模糊动态规划的直接负荷控制策略研究

随着社会经济发展，电子负荷形状随之发生显著变化，具体表现为负荷率不断下降，高峰负荷持续增大，负荷峰谷差进一步拉大，为些采取负荷管理手段进行负荷控制迫在眉睫。直接负荷控制（DLC）作为简单实用的负荷管理手段，受到广泛关注。结合直接负荷控制的控制策略特点，提出利用模糊动态规划（FDP）原理进行负荷控制，从电子部门、电子系统和用户三方各自效益考虑需采取直接负荷控制的最佳策略，经分析可知采取适当的控制策略能使系统各参与方效益最优。     

计及负荷储能特性的微网荷储协调联络线功率波动平抑策略

以微网整体参与市场交易为背景,计及直接控制负荷的储能特性,提出采用电池储能和直接负荷控制(DLC)协调的微网联络线功率波动平抑策略。将DLC视为储能资源的调控行为,建立基于负荷储能特性的DLC模型。在此基础上,以经济效益最大为目标,考虑DLC作用,基于两阶段随机规划优化微网短期交易行为。以经济性和不影响用户用能体验为原则,提出考虑负荷运行状态的微网联络线功率波动完全平抑方案。最后,通过仿真算例验证了所提策略的有效性。     

Climate change,extreme winter weather and electricity production costs

We analyze the characteristics of the Northeast US’s PJM wholesale electricity market production cost and supply curve during the most extreme winter weather event in modern meteorological history within the PJM territory. It is seemingly ironic that the cause of such extremely cold weather events is global warming. The experience from this event demonstrates that the annual-summer-peak-centric nature of the PJM capacity planning process does not address the adequacy of supply during the winter. The PJM production cost curve is estimated and compared across recent winter season peak months to understand how large the price responsiveness to load changes can be during extreme winter weather events and how winter weather events can reduce system reliability for a summer-capacity-planning-centric power market. Therefore, PJM and other power pools (such as ERCOT in Texas) have not considered secondary peak seasons in capacity planning.     

国外典型电网负荷特性分析

负荷特性分析是电力系统运行管理中的一个重要环节,掌握电力负荷特性的变化规律和发展趋势是建立负荷预测模型的基础。在参考相关文献的基础上,建立了较为完善的负荷特性指标体系,并收集了日本东京、美国东北部电网、纽约电网等多个地区电网的负荷数据,对上述地区的负荷特性曲线进行了深入分析,以期为我国电网的负荷特性研究提供参考。     

冲击测量用数字记录仪校验系统的建立和应用

介绍了冲击测量用数字记录仪校验系统的组成、校验项目及方法,并给出了对Tek2440型数字记录仪校验的结果。结果表明,它能满足IEC标准的要求。     

Fuzzy logic-based direct load control of air conditioning loads considering nodal reliability characteristics in restructured power systems

A fuzzy logic-based direct load control (DLC) scheme of large air conditioning loads (ACL), which considers the reliability characteristics of nodes where the ACL are connected, is proposed for restructured power systems. Transmission system reliability is integrated into the determination procedure of the DLC scheme of ACL using nodal reliability indices. Fuzzy dynamic programming (FDP) is utilized to determine the optimal DLC scheme of ACL which can achieve a good tradeoff among peak load shaving, system operating cost reduction and system reliability improvement. The IEEE reliability test system (RTS) is used to illustrate the proposed technique.     

GM(1,2)短期现货电价灰色预测模型

在电力市场中,电价预测对市场参与者具有非常重要的意义。该文检验了GM(1,2)灰色模型在现货电价预测中的应用效果。在对GM(1,2)模型进行修正的基础上,分别建立了计及负荷因子的预测模型和计及预测时刻前一小时电价的预测模型,并对模型进行了等维新息处理。对美国PJM电力市场的峰荷时段、腰荷时段和低谷时段的LMP实时电价分别进行了预测。预测结果表明,计及预测时刻前一小时电价的预测模型具有较好的预测效果。     

美国PJM电力市场及其对我国电力市场化改革的启示

美国PJM控制区(位于美国东北部的一个区域电力系统)的电力市场运作是北美建立竞争区域电力市场的典范，其成功经验值得中国借鉴。文中总结了美国PJM电力市场的发展过程、市场组织结构和市场交易机制，分析了其成功的几大因素，并针对中国特点提出：为了保征电力系统的安全运行和电力市场的有效运作，中国的电力市场交易应该以合同交易为主，随着市场需求发展多种交易类型，通过制定有效的市场规则减少市场操纵力，同时应建立明确的供电责任机制。     

A simulation approach to balancing annual risk and reward in retail electrical power markets

Retail electrical power marketers, also known as retailers, typically set up contracts with suppliers to secure electricity at fixed prices on the one hand and with end users to meet their load requirements at agreed upon rates on the other hand. Providing future load requirements accurately to the suppliers is an integral part of these supply contracts. In this paper, we analyze a series of retailer strategies to determine future loads using simulation at the hourly level for a simulated year (8760 hr). We provide numerical results based on actual data for the PJM market and provide insights into these retailer strategies.     

Control of tap change under load transformers through the use ofprogrammable logic controllers

This paper describes a method developed by Pennsylvania Power and Light Company (PP&L) for applying programmable logic controllers to control tap change under load (TCUL) power transformers. Equipment was identified, and a set of software programs developed, to completely replace the existing analog-based TCUL control systems. There is a significant cost savings from this approach, and PP&L expects an increase in the reliability of the TCUL controls from this design, as well as fewer operations of the TCUL equipment. Several additional functions and alarms were implemented in the new design which will enhance the operation of these transformers     

基于机会约束规划的直接负荷控制及可中断负荷联合优化调度研究

为充分利用需求响应资源,可对不同需求响应资源进行整合。本文以调度成本最低为目标函数,构建了含直接负荷控制和可中断负荷的优化模型。对比了直接负荷控制及可中断负荷在受控量、受控时间、补偿价格等方面的异同,重点分析了两者在负荷反弹方面的差异。采用机会约束考虑了负荷预测的不确定性,并将机会约束转化为其确定性等价形式。采用拉格朗日松弛法对确定性模型求解,并采用蒙特卡罗模拟对机会约束置信水平进行验证。算例表明模型综合了直接负荷控制移峰和可中断负荷削峰特点,可有效降低系统高峰时段负荷,避免二次负荷高峰的产生。     

Assessment of the COVID-19 pandemic effect on regional electricity generation mix in NYISO,MISO, and PJM markets

This paper explores the impacts of the stay-at-home advisory issued in response to the COVID-19 pandemic on regional electricity generation fuel mixes for the three major RTOs: NYISO, MISO, and PJM. We find that the COVID-19 pandemic affected these regional markets differently, although one common finding is that overall electricity generation declined after the stay-at-home advisories were issued. We also empirically tested the impact of the stay-at-home advisories on electricity generation for different fuel types.     

PJM输电权运行机制及其在我国区域电力市场阻塞管理中的应用

PJM电力市场采用节点边际电价(LMP)进行阻塞管理,利用点对点的金融性输电权(FTR)作为金融工具来分摊阻塞盈余、规避节点电价不稳定带来的市场风险。主要介绍了PJM电力市场中输电权的种类、输电权拍卖市场的特点、出清机制和结算方法。在此基础上,对我国区域电力市场的阻塞管理及输电权市场的设计提出了一些建议。     

电力物联网可信树形批量认证机制

电力物联网设备需要进行可信度量,然而现有数据处理架构存在云端压力过大的问题,现有可信度量架构也存在效率低下、消耗过大等问题.提出一种适用于云边协同电力物联网环境的基于树形结构的可信批量认证机制.该机制采用云边端协同的边缘计算架构缓解云平台压力,设备采用一种轻量级可信架构进行可信度量,获取度量信息;非平衡哈希树存储结构在...