1 Small Wind Energy - International Standards 2 Small Wind Energy - International Standards Overview EC machinery Directive IEC 61400-2 IEC 61400-11 IEC 61400-12-1 1
3 EC Machinery Directive (1) 2006/42/EC Valid for all assemblies fitted with a drive system other than directly applied human or animal effort Full responsible for certifying the conformity: Manufacturer Natural or legal person - placing it on market - putting it into service Compulsory since 29 December 2009 Recasting of 95/16/EC 4 EC Machinery Directive (2) Key requirements Risk management mandatory for the design process Risk reduction is a design prerequisite Safety and reliability of control systems Control systems must be designed and constructed in such a way as to prevent hazardous situations from arising reasonably foreseeable human error during operation does not lead to hazardous situations the machinery must not prevented from stopping if the command has already been given Stopping The emergency stop function must be available and operational at all times, regardless of the operating mode. Machinery must be fitted with a control device whereby the machinery can be brought safely to a complete stop. 2
5 EC Machinery Directive (3) Presumption of conformity If manufactured in conformity with a harmonized standard in the respective country Satisfaction of relevant health and safety requirements Technical documentation available Instructions for user in understandable language EC declaration of conformity, CE marking on the product European standard: EN 61400-2:2006 Wind turbines Part 2: Design requirements for small wind turbines) Definition of mechanical and electrical design parameters Definition of wind speed characteristics and environmental conditions Choice of applicable design procedures Functional requirements to the safety system Necessary measurements and testing Validation of the design loads Endurance field testing 6 EC Machinery Directive (4) Risk management (examples) Cause over speed material defects wrong dimensioning imbalance, resonance blade contact with the mast Controller software error Wrong wind class too much turbulence Wrong load assumptions of internal and external forces Lack of field testing No proof for load simulations Permanently not connected to grid/battery/power source (reasonably foreseeable misuse) Cable breakage (internal / external) Lightning strike Result Unintended loosening of screws damage / loss of rotor blade collapse of the mast Failure of electrical control system Human injuries Structural instability Component safety Frequent emergency stops drastic reduction of lifetime Human injuries Damages of system components 3
7 Risks from small wind turbines (1) 8 Risks from small wind turbines (2) 4
9 Risks from small wind turbines (3) 10 Risks from small wind turbines (4) 5
11 Risks from small wind turbines (5) 12 Redundancy? 6
13 Sources of critical failures Wearing down of brake pads Deficit of break fluid Wire rope breakage Electric rope winch failure Battery failure 1 overspeed Generator failure Cable breakage Load not connected 14 Intended use (1) Summary Field of application Feeding to the grid Battery charging Water pumping... Mechanical loading from wind, etc. Choice or definition of appropriate wind classes (EN 61400-2) according to site conditions Maximum rotor speed Design lifetime Mast height Turbulence class Rated power Limits of the system External connections Sound level 7
15 Intended use (2) EN 61400-2 wind classes Wind class Annual average [m/s] v_ref [m/s] I 10 50 II 8,5 42,5 III 7,5 37,5 IV 6 30 frequency 14% 12% 10% 8% 6% 4% 2% 0% Rayleigh v=10 v=8,5 v=7,5 v=6 0 5 10 15 20 25 wind velocity [m/s] 16 Intended use (3) mechanical loads 8
17 Intended use (4) turbulence intensity Turbulence intensity 70% 60% 50% 40% 30% 20% 10% 0% sigma_1/v_hub (18%) sigma_1/v_hub (25%) 0 10 20 30 40 wind speed [m/s] 19 Safety requirements (1) International standards IEC 61400-2: Design requirements for small wind turbines (< 200m²) Over speed Redundant system, i.e. the failure of one component (e.g. the generator) may not result in exceeding the design rotor speed Additional brake system needed Choice of wind class according to on site wind conditions Average annual wind velocity Survival wind velocity Main switch Disconnection of electrical equipment Stopping of the rotor for maintenance or before/at storm Operating instructions Manual / automatic shutdown before / at extreme wind conditions Operation and maintenance Stability against collapse, lightning protection, icing 9
21 Field testing 24 Product labelling European market CE-mark of conformity Manufacturer declares conformity with European standards (Machinery directive, low voltage directive, EMC directive) Risk management mandatory for the design process EN 61400-2 is the harmonized standard Power curve Measured according to EN 61400-12 Noise emissions Measured according to EN 61400-11 Complete documentation 10
25 CONTACT INENSUS GmbH Am Stollen 19 D 38640 Goslar Germany www.inensus.com Tel +49 (5321) 38271-0 Fax +49 (5321) 38271-99 INENSUS West Africa S.A.R.L. 10, Avenue Faidherbe, B.P. 397 Dakar Sénégal 11