Slide 1

vestas.com Michael Kennedy Lead Electrical Engineer Vestas Americas Wind Turbine Design Requirements and Control Considerations A brief look at the modern wind turbines for power generation. Slide 2 2 | Presentation title, May 1, 2015 International Society of Automation The major parts of a turbine Tower Nacelle (the box at the top) Blades The Central Plains project site consists of 33 V90-3.0MW wind turbines in Kansas, USA. Wind farms are often located in remote locations and one important factor is the proximity a power transmission system for the turbines to connect to. Slide 3 3 | Presentation title, May 1, 2015 International Society of Automation The scale of power generation turbines Rough dimensions Tower height ~ 67 - 115m (in about 4 or 5 sections) Tower Maximum diameter ~4.2m Nacelle ~ 50 70 tons Blades ~40m long (one piece) Constraints Shipping the turbines to site. Ships, Roads. Rail. The grid connection. Available transmission lines. Fault levels System stability. Wind speed Cut in ~ 4m/s (9mph) Peak Power ~ 15m/s Cut out ~ 25m/s Withstand speed 155MPH (Flat out in a fast Mercedes!) Slide 4 4 | Presentation title, May 1, 2015 International Society of Automation What the Vestas model name means. V90 has a 90 meter diameter blade swept area. Slide 5 5 | Presentation title, May 1, 2015 International Society of Automation The Nacelle V90-3.0 MW Slide 6 6 | Presentation title, May 1, 2015 International Society of Automation Circuit configurations Simple Induction Turbine (V82 1.65MW) {Type A} Advantage: Simple and robust Disavantage: Not all new grid requirements can be met. Rotor Controlled Turbine (V80/90 2.0MW) {Type B} Advantage: More control for better energy harvest. Disavantage: More complex than Simple Induction Generator Double Fed Induction Generator (V90 3MW) {Type C} Advantages: Yet more control for better performance Disavantage: More expensive. Full Converter Permanent Magnet Generator (V112 3MW) {Type D} Advantages: Best energy capture and grid performance Disavantage: More expensive. Complex logistics (56m blades) Slide 7 7 | Presentation title, May 1, 2015 International Society of Automation Why so many models? Theres more to the wind than meets the eye! Different site conditions - Average and Maximum wind speed conditions. Sound power restrictions. Different Types of terrain. Cliffs or rising slopes. Onshore or Offshore. Trees of vegetation. Turbulence? Climatic extremes Arctic or Tropical. Ice days. Lightning days. Different grid conditions Voltage support required (variable power factor). Power constrants. Flicker constraints. Harmonic emmissions. Weak connection STATCOM required. Area available many hectares of few. Turbine spacing wake effects. Slide 8 8 | Presentation title, May 1, 2015 International Society of Automation The power curve. The energy yield. Slide 9 9 | Presentation title, May 1, 2015 International Society of Automation What we measure at each turbine... Wind speed and wind direction. Temperature and humidity. Blade pitch angle. Rotational speed of the generator. Grid conditions voltage, phase balance, frequency. Turbine output current, power factor and power. Each turbine is a stand-alone power station! Automatic synchronization. Full electrical protection. Power regulation and voltage support are avaliable on some models. Slide 10 10 | Presentation title, May 1, 2015 International Society of Automation What we measure at each turbine... The measured temperatures are: Generator G temperature Generator g temperature Transformer temperature Ambient temperature Nacelle temperature Yaw rim temperature Pitch oil temperature Pitch oil accumulator temperature Water temp. before cooler Water temp. after cooler Water temp. after cooler 2 Gear oil temp. after exchanger Gear oil temperature Thyristor temperature Main panel temperature UPS panel temperature Gear bearing front temperature Gear bearing rear temperature Gear bearing rear gen. side temp. Interm. gear front temperature Interm. gear rear temperature Generator bearing front temp. Generator bearing rear temp. Main bearing temperature Main bearing oil temperature Transformer W1 temperature Transformer W2 temperature Transformer W3 temperature Control panel temperature Top box panel temperature Phase comp. panel temperature Tower base temperature Hub panel temperature Generator G W1 temperature Generator G W2 temperature Generator G W3 temperature The measured pressures are: Disc brake Disc brake accumulator tank Yaw brake Yaw brake accumulator tank Gear oil Gear oil level pressure Accumulators for blade A,B and C (measured by hub computer) Feeding pump for blade hydraulics (measured by hub computer) Slide 11 11 | Presentation title, May 1, 2015 International Society of Automation What we control at each turbine... Blade Angle The hub computer continuously monitors the angle of the blades, also called the blade position. The blade position is determined by the main computer, which continuously sends a wanted blade position to the hub computer. Rotational Speed The rotational speed is constantly monitored. If an overspeed situation occurs, the wind turbine is stopped by the computer. The same applies to the generator rotational speed. If the speed exceeds a previously set limit, the computer stops the wind turbine. Acceleration The acceleration used during the start up procedure is calculated by means of the rotational speed measurements. To achieve a cut-in to the grid as soft as possible, the acceleration is softened by turning the blades until the wanted acceleration is reached. Cut-in to the Grid (The rotational speed is also used to decide when to cut in the generator. )A cut-in sequence is as follows: The speed is controlled to a few rotations over the synchronous rotational speed for the generator. The computer starts the thyristors with a small opening angle and then the opening angle is controlled until the thyristors are completely open. While the thyristors are opening, the blades are turned into starting position. When the thyristors are completely open, the thyristor by-pass switch is connected. Slide 12 12 | Presentation title, May 1, 2015 International Society of Automation Protecting the turbine... Electrical over-voltage protection. The wind turbine control system is protected against transients occurring via the main cables (the grid). The over-voltage protection system is installed in the power cabinet and has a nominal protection level of 15 kA and a maximum current equalization capacity of 40 kA per conductor. The voltage protection level is 2 kV. The remaining voltage is equalized by further protection barriers built into the control system. Induced Transients. The computer is protected from transient over-voltage from the multi-cable in the nacelle by means of barriers installed in the connector box for sensor inputs in the nacelle. The barriers couple transient over-voltages into earth. Barriers on the communication cable will protect the computer when they are fitted with internal analogue modem or current loop interface. The barrier couples the differentials and transient over-voltages into the computer earth connection. Insulation barriers are integrated into the control system. They insulate input and output signals from the measuring point by means of transformers or opto-electric barriers. These barriers are designed to withstand a 2kV potential. Controller inputs can withstand at least +- 1kV 1.2/50 S surges. Thyristors are protected against over-voltage transients with a barrier at the snubber board. Slide 13 13 | Presentation title, May 1, 2015 International Society of Automation Protecting the turbine... Lightning protection system (LPS) The lightning protection system consists of: Lightning receptors in the blade. Down conducting system. A system to conduct the lightning current down through the wind turbine to help avoid or minimise damage to the LPS system itself or other parts of the wind turbine. Protection against over-voltage and over-current. Shielding against magnetic and electrical fields. Earthing (Grounding) System bonding Bonding for all components ensures that lightning energy is conducted to earth. The machine base frame performs protection of the components in the nacelle. The components, which are not directly mounted to the bed, are connected with earthing cables. At the rear of the nacelle there is also a lightning conductor that extends considerably higher than the wind sensors. Slide 14 14 | Presentation title, May 1, 2015 International Society of Automation Standards for the turbines... High Voltage ac circuit breakers IEC 60056 High Voltage testing techniques IEC 60060 Power Capacitors IEC 60070 Insulating bushings for ac voltage above 1kV IEC 60137 Insulation co-ordination BS EN 60071 AC Disconnectors and earth switches BS EN 60129 Current Transformers IEC 60185 Voltage Transformers IEC 60186 High Voltage switches IEC 60265 Disconnectors and Fuses IEC 60269 Flame Retardant Standard for MV Cables IEC 60332 Transformers IEC 60071/IEC 60076 Generator IEC 60034 Specification for sulphur hexafluoride for electrical equipment IEC 60376 Rotating electrical machines IEC 34 Dimensions and output ratings for rotating electrical machines IEC 72 & IEC 72A Classification of insulation, materials for electrical machinery IEC 85 Safety of machinery Electrical equipment of machines IEC 60204-1 Slide 15 15 | Presentation title, May 1, 2015 International Society of Automation Standards for the turbines... Design Codes I/O Network System Salt Mist Test IEC 60068-2-52 Damp Head, Cyclic IEC 60068-2-30 Vibration Sinus IEC 60068-2-6 Cold IEC 60068-2-1 Enclosure IEC 60529 Damp Head, Steady State IEC 60068-2-56 Vibration Random IEC 60068-2-64 Dry Heat IEC 60068-2-2 Temperature Shock IEC 60068-2-14 Free Fall IEC 60068-2-32 Slide 16 16 | Presentation title, May 1, 2015 International Society of Automation Main Control 3 blocks called main controller, pitch regulator and power controller. Slide 17 17 | Presentation title, May 1, 2015 International Society of Automation The main controller is responsible for... Maximization of the amount of produced energy Limitation of mechanical loads according to design limits Limitation of acoustical noise Maintaining of high power quality Slide 18 18 | Presentation title, May 1, 2015 International Society of Automation Less Noise, Igor! Some turbines are capable of power reduction to control the noise. Slide 19 19 | Presentation title, May 1, 2015 International Society of Automation More power, Igor! 2 Scenarios for control Partial Load Operation Full Load Operation External power control factors Nominal power or User setpoint Too much, Igor! Decrease power due to high generator temperature. high gear temperature. high transformer temperature. high or low voltage. Slide 20 20 | Presentation title, May 1, 2015 International Society of Automation Controls Active Tower Damping turbines with low tower natural inherent frequency are equipped with accelerometers, - turbines are paused, if acceleration level exceeds maximum allowable value. Thrust Limitation. Individual Pitch tower wake Start-up and Shutdown Star- / Delta Connection Inrush reduction Anti-massive start Slide 21 21 | Presentation title, May 1, 2015 International Society of Automation Pitch control Maximization of the amount of produced energy Slide 22 22 | Presentation title, May 1, 2015 International Society of Automation What the authorities want. National Authorities Federal Energy Regulatory Commission (FERC) North American Electric Reliability Corporation (NERC) Regional Transmission Organizations (RTO)/Independent System Operators (ISO) Rules and Regulations FERC 661/A Low Voltage Ride Through. (LVRT) Reliability region rules Utility connections are guided by the Large Generator Interconnection Agreement. Slide 23 23 | Presentation title, May 1, 2015 International Society of Automation To survive... Low Voltage Ride Through Slide 24 24 | Presentation title, May 1, 2015 International Society of Automation Within limits. Reactive Power Control Fixed capacitors or Variable within the limits of the generator/transformer. Slide 25 25 | Presentation title, May 1, 2015 International Society of Automation The control system layout. Slide 26 26 | Presentation title, May 1, 2015 International Society of Automation Processor & I/O Controllers Slide 27 27 | Presentation title, May 1, 2015 International Society of Automation Measurement of lightning Slide 28 28 | Presentation title, May 1, 2015 International Society of Automation Counters & I/O Slide 29 29 | Presentation title, May 1, 2015 International Society of Automation CT6211/15 Serial Communication fibre/electrical RS422/RS485 Slide 30 30 | Presentation title, May 1, 2015 International Society of Automation Converter Processor & Interface. Slide 31 31 | Presentation title, May 1, 2015 International Society of Automation Vestas VPN Slide 32 32 | Presentation title, May 1, 2015 International Society of Automation Interface options Hardwire or DNP3 Slide 33 33 | Presentation title, May 1, 2015 International Society of Automation Interface Options Modbus or OPC Slide 34 34 | Presentation title, May 1, 2015 International Society of Automation SCADA Vestas Online Business Slide 35 35 | Presentation title, May 1, 2015 International Society of Automation Vestas Online Business Slide 36 36 | Presentation title, May 1, 2015 International Society of Automation Vestas Online Business Slide 37 37 | Presentation title, May 1, 2015 International Society of Automation Vestas Online Business Slide 38 38 | Presentation title, May 1, 2015 International Society of Automation Trending the Data. Slide 39 vestas.com Michael Kennedy Lead Electrical Engineer Vestas Americas Thank you for your attention Copyright Notice The documents are created by Vestas Wind Systems A/S and contain copyrighted material, trademarks, and other proprietary information. All rights reserved. No part of the documents may be reproduced or copied in any form or by any meanssuch as graphic, electronic, or mechanical, including photocopying, taping, or information storage and retrieval systems without the prior written permission of Vestas Wind Systems A/S. The use of these documents by you, or anyone else authorized by you, is prohibited unless specifically permitted by Vestas Wind Systems A/S. You may not alter or remove any trademark, copyright or other notice from the documents. The documents are provided as is and Vestas Wind Systems A/S shall not have any responsibility or liability whatsoever for the results of use of the documents by you.