IEC TS 62257-7-2:2022

Recommendations for renewable energy and hybrid systems for rural electrification - Part 7-2: Generator set - Off-grid wind turbines

IEC TS 62257-7-2:2022 applies to all small wind turbines (SWTs) with a swept area smaller than or equal to 200 m2, and designed for supplying electrical power to isolated sites used in systems as described in IEC TS 62257-2.
This document is not an exhaustive resource for the design, installation, operation or maintenance of small wind turbines and wind power systems, but is more focused on recommendations to provide strategies on selection and criteria which may affect the use of a small wind power system (SWPS) in a rural electrification project.
The aim of this document is to provide users with the appropriate levels of reliability and safety of the equipment during its estimated service lifespan.

General Information

• Status: Published
• Publication Date: 15-Mar-2022
• ICS: 27.180 - Wind turbine energy systems
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: JWG 1 - TC 82/JWG 1
• Current Stage: PPUB - Publication issued
• Start Date: 12-Apr-2022
• Completion Date: 16-Mar-2022

Standards Content (Sample)

IEC TS 62257-7-2 ®
Edition 1.0 2022-03
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 7-2: Generator set – Off-grid wind turbines
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IEC TS 62257-7-2 ®
Edition 1.0 2022-03
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 7-2: Generator set – Off-grid wind turbines

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.180 ISBN 978-2-8322-1087-2

– 2 – IEC TS 62257-7-2:2022 © IEC 2022
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 10
4 Symbols and abbreviated terms . 15
4.1 Abbreviated terms . 15
4.2 Symbols . 16
5 Wind turbine (WT) . 16
5.1 Types of wind turbines . 16
5.1.1 Horizontal axis wind turbine (HAWT) . 16
5.1.2 Vertical axis wind turbine (VAWT) . 17
5.1.3 SWT classes. 18
5.2 General characteristics of SWT . 18
5.2.1 Basic technical characteristics . 18
5.2.2 Most important technical characteristics . 19
5.3 Working conditions of SWT . 20
6 Off-grid Small Wind Power Systems (SWPS) . 20
6.1 General . 20
6.2 Major components in SWPS . 20
6.2.1 SWT . 20
6.2.2 Tower . 21
6.2.3 Controller . 22
6.2.4 Brake . 22
6.2.5 Inverter . 23
6.2.6 Storage system . 23
6.2.7 Dump load . 23
6.3 Design Procedure of SWPS . 23
6.3.1 General . 23
6.3.2 Wind resource assessment . 23
6.3.3 Site assessment . 24
6.3.4 Determine the capacity of the SWPS . 24
6.3.5 Select SWT . 24
6.4 Configuration of SWPS . 24
6.4.1 General . 24
6.4.2 Layout SWT(s) on site . 28
7 Selection of SWPS . 28
7.1 General . 28
7.2 Selection criteria . 29
7.2.1 General factors in selection of SWT . 29
7.2.2 Rule of thumb . 29
7.2.3 Wind turbine height . 29
7.2.4 Turbulence . 30
7.3 Design of a microgrid or Isolated Microgrid with SWT . 30
7.3.1 Meet national rural grid standards. 30
7.3.2 Design microgrid and wiring into households . 30

8 Safety issues . 30
8.1 General . 30
8.2 General . 30
8.3 Personal safety . 31
8.3.1 Safety training and regulation following . 31
8.3.2 Basic safety guidelines . 31
8.4 Equipment safety . 32
8.4.1 SWT . 32
8.4.2 System current and voltage . 32
8.4.3 Wiring and disconnection requirements . 32
8.4.4 Grounding. 32
8.4.5 Other safety issues and anti-theft . 33
8.5 SWPS safety for isolated microgrid . 33
8.5.1 System safety . 33
8.5.2 Extreme climate proof . 34
8.5.3 High elevation for electronics . 34
8.6 Protection against electric shock and fire . 34
9 SWT and SWPS installation . 34
9.1 General . 34
9.1.1 Overview . 34
9.1.2 General installation methods . 35
9.1.3 Rooftop installation . 35
9.1.4 Verticality . 35
9.2 Installation of SWPS of isolated microgrid . 36
9.2.1 Transportation . 36
9.2.2 Preparations . 36
9.2.3 Infrastructure . 36
9.2.4 Civil works . 37
9.2.5 Installation of equipment . 38
10 Tests and acceptance . 40
10.1 General . 40
10.2 Individual equipment test . 40
10.3 System self-test . 40
10.4 Acceptance test . 40
10.4.1 General . 40
10.4.2 Preparation . 41
10.4.3 Documentation . 41
10.4.4 Commissioning . 41
10.4.5 Agreement . 42
11 Operation and maintenance . 42
11.1 General . 42
11.2 Safety . 42
11.3 Operation and maintenance procedures . 42
11.4 General inspection, routine and troubleshooting. 43
11.4.1 Inspection . 43
11.4.2 Check list . 43
11.5 Troubleshooting . 43
12 Marking and documentation . 44
...