Design

Recommended design practices and procedures for storage, location, mounting, ventilation, instrumentation, preassembly, assembly, and charging of vented lead-acid batteries are provided. Required safety practices are also included. These recommended practices are applicable to all stationary applications. Specific applications, such as emergency lighting units, semiportable equipment, and alternate energy applications, may have other appropriate practices and are beyond the scope of this recommended practice.

The collector system grounding for wind power plants (WPPs) is the primary concern of this guide. This guide is not intended for the WPP substation; however, since the substation is typically interconnected with the collector system, its design might affect or be affected by the collector system. With proper consideration, the methods described herein could be used in determining the impact of the collector system on substation safety and vice versa. Quantitative analysis of the effects of lightning surges is beyond the scope of this document. Similarly, this guide does not cover offshore wind power plants, battery energy storage facilities, solar power plants, or substation grounding.

Application of this standard includes: (1) Stationary battery energy storage system (BESS) and mobile BESS; (2) Carrier of BESS, including but not limited to lead acid battery, lithiumion battery, flow battery, and sodium-sulfur battery; (3) BESS used in electric power systems (EPS). Also provided in this standard are alternatives for connection (including DR interconnection), design, operation, and maintenance of stationary or mobile BESS used in EPS. Introduction, overview, and engineering issues related to the BESS are given.

IEC TS 62915:2018(E) sets forth a uniform approach to maintain type approval, design and safety qualification of terrestrial PV modules that have undergone, or will undergo modification from their originally assessed design. Changes in material selection, components and manufacturing process can impact electrical performance, reliability and safety of the modified product. This document lists typical modifications and the resulting requirements for retesting based on the different test standards. This document is closely related to the IEC 61215 and IEC 61730 series of standards.

IEC TS 62738:2018(E) sets out general guidelines and recommendations for the design and installation of ground-mounted photovoltaic (PV) power plants. A PV power plant is defined within this document as a grid-connected, ground-mounted system comprising multiple PV arrays and interconnected directly to a utility’s medium voltage or high voltage grid. Additional criteria is that PV power plants are restricted from access by non-qualified persons and are continuously monitored for safety and protection, either by on-site personnel or by active remote monitoring. Technical areas addressed are those that largely distinguish PV power plants from smaller, more conventional installations, including ground mounted array configurations, cable routing methods, cable selection, overcurrent protection strategies, equipotential bonding over large geographical areas, and equipment considerations. Safety and design requirements are referenced to the applicable requirements of IEC 62548 to address distinct differences relative to the design requirements for residential, commercial and other non-power plant applications.

IEC TS 61400-3-2:2019 specifies additional requirements for assessment of the external conditions at a floating offshore wind turbine (FOWT) site and specifies essential design requirements to ensure the engineering integrity of FOWTs. Its purpose is to provide an appropriate level of protection against damage from all hazards during the planned lifetime. This document focuses on the engineering integrity of the structural components of a FOWT but is also concerned with subsystems such as control and protection mechanisms, internal electrical systems and mechanical systems. A wind turbine is considered as a FOWT if the floating substructure is subject to hydrodynamic loading and supported by buoyancy and a station-keeping system. A FOWT encompasses five principal subsystems: the RNA, the tower, the floating substructure, the station-keeping system and the on-board machinery, equipment and systems that are not part of the RNA. The following types of floating substructures are explicitly considered within the context of this document: a) ship-shaped structures and barges, b) semi-submersibles (Semi), c) spar buoys (Spar), d) tension-leg platforms/buoys (TLP / TLB). In addition to the structural types listed above, this document generally covers other floating platforms intended to support wind turbines. These other structures can have a great range of variability in geometry and structural forms and, therefore, can be only partly covered by the requirements of this document. In other cases, specific requirements stated in this document can be found not to apply to all or part of a structure under design. In all the above cases, conformity with this document will require that the design is based upon its underpinning principles and achieves a level of safety equivalent, or superior, to the level implicit in it. This document is applicable to unmanned floating structures with one single horizontal axis turbine. Additional considerations might be needed for multi-turbine units on a single floating substructure, vertical-axis wind turbines, or combined wind/wave energy systems. This document is to be used together with the appropriate IEC and ISO standards mentioned in Clause 2. In particular, this document is intended to be fully consistent with the requirements of IEC 61400-1 and IEC 61400-3-1. The safety level of the FOWT designed according to this document is to be at or exceed the level inherent in IEC 61400‑1 and IEC 61400-3-1.

IEC TR 60904-14:2020 provides guidelines for measurements of the maximum power (Pmax) output of single-junction photovoltaic (PV) modules and for reporting at standard test conditions (STC) in industrial production line settings. As it is desirable to have consistent measurement practices across the industry, this document describes the following features of such measurements: - Essential elements, in order to provide common understanding; - Common issues or complications; - Sources of error and uncertainty, including recommendations to minimize them.

IEC 62817:2014+A1:2017 is a design qualification standard applicable to solar trackers for photovoltaic systems, but may be used for trackers in other solar applications. The standard defines test procedures for both key components and for the complete tracker system. In some cases, test procedures describe methods to measure and/or calculate parameters to be reported in the defined tracker specification sheet. In other cases, the test procedure results in a pass/fail criterion. This standard ensures the user of the said tracker that parameters reported in the specification sheet were measured by consistent and accepted industry procedures. The tests with pass/fail criteria are engineered with the purpose of separating tracker designs that are likely to have early failures from those designs that are sound and suitable for use as specified by the manufacturer. This consolidated version consists of the first edition (2014) and its amendment 1 (2017). Therefore, no need to order amendment in addition to this publication.

IEC 62548:2016 sets out design requirements for photovoltaic (PV) arrays including DC array wiring, electrical protection devices, switching and earthing provisions. The scope includes all parts of the PV array up to but not including energy storage devices, power conversion equipment or loads. An exception is that provisions relating to power conversion equipment are covered only where DC safety issues are involved. The interconnection of small DC conditioning units intended for connection to PV modules are also included. The object of this document is to address the design safety requirements arising from the particular characteristics of photovoltaic systems. Direct current systems, and PV arrays in particular, pose some hazards in addition to those derived from conventional AC power systems, including the ability to produce and sustain electrical arcs with currents that are not greater than normal operating currents.

Verifies system design and performance of stand-alone photovoltaic systems. The performance test consists of a check of the functionality, the autonomy and ability to recover after periods of low state-of-charge of the battery, and hence gives reasonable assurance that the system will not fail prematurely. The testing conditions are intended to represent the majority of climatic zones for which these systems are designed.