IEC 61970-456:2021属于IEC 61970-450至IEC 61970-499系列，该系列作为一个整体，在抽象层次上定义了用于电力系统分析应用程序、控制中心和/或控制中心组件之间传输数据的内容和交换机制。 本文档的目的是严格定义CIM中的类子集、类属性和角色，以描述状态估计、潮流和其他类似应用程序的结果，这些应用程序产生了电力网络的稳态解决方案，这些应用程序包含在本文档中的一组使用案例中。 本文档面向两个不同的受众，即数据生产者和数据接收者，可以从这两个角度阅读。从数据制作者使用的模型导出软件的角度来看，本文件定义了制作者如何描述网络案例的实例，以使其可供其他程序使用。从用户的角度来看，文档定义了导入软件必须能够解释的内容，以便使用潮流情况。 有许多不同的用例需要使用本文档，它们在每种情况下应用文档的方式不同。 预期实施者将考虑他们希望涵盖的用例，以了解他们必须涵盖的不同选项的程度。例如，在某些情况下，本文档中定义的配置文件将用于交换启动条件而不是已解决的条件，因此，如果这是一个重要的用例，则意味着消费者应用程序需要能够处理未解决的状态以及满足某些解决方案标准的状态。 第三版取消并取代2018年出版的第二版。本版为技术修订版。它基于日期为2020年的IEC 61970 UML版本“IEC61970CIM17v40”- 08-24. 本版本包括与前一版本相比的以下重大技术变更: a） 更新以支持CIM17（IEC 61970-301:2020+AMD1），并与IEC 61970-452:ED4保持一致。 b） 将PowerElectronicsConnection、PowerElectronicsUnit和PowerElectronicsWindUnit类添加到稳态假设（SSH）配置文件中，以匹配对IEC 61970-452第4版核心设备配置文件所做的更改。 c） 增加了本文件中使用的相关术语。 d） 澄清设备的使用。在役人员和设备。正常运行。

IEC 61970-456:2021 belongs to the IEC 61970-450 to IEC 61970-499 series that, taken as a whole, defines at an abstract level the content and exchange mechanisms used for data transmitted between power system analyses applications, control centres and/or control centre components. The purpose of this document is to rigorously define the subset of classes, class attributes, and roles from the CIM necessary to describe the result of state estimation, power flow and other similar applications that produce a steady-state solution of a power network, under a set of use cases which are included informatively in this document. This document is intended for two distinct audiences, data producers and data recipients, and can be read from those two perspectives. From the standpoint of model export software used by a data producer, the document defines how a producer may describe an instance of a network case in order to make it available to some other program. From the standpoint of a consumer, the document defines what that importing software must be able to interpret in order to consume power flow cases. There are many different use cases for which use of this document is expected and they differ in the way that the document will be applied in each case. Implementers are expected to consider what use cases they wish to cover in order to know the extent of different options they must cover. As an example, the profiles defined in this document will be used in some cases to exchange starting conditions rather than solved conditions, so if this is an important use case, it means that a consumer application needs to be able to handle an unsolved state as well as one which has met some solution criteria. This third edition cancels and replaces the second edition published in 2018. This edition constitutes a technical revision. It is based on the IEC 61970 UML version ‘IEC61970CIM17v40’, dated 2020-08-24. This edition includes the following significant technical changes with respect to the previous edition: a) Updated to support CIM17 (IEC 61970-301:2020+AMD1) and align with IEC 61970‑452:ED4. b) The classes PowerElectronicsConnection, PowerElectronicsUnit and PowerElectronicsWindUnit are added to the Steady State Hypothesis (SSH) profile to match the changes done for Edition 4 of IEC 61970-452, Core Equipment profile. c) Added relevant terms used in this document. d) Clarified use of Equipment.inService and Equipment.normallyInService.