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CHAPTER 1

INTRODUCTION

Wind energy is one of the new and renewable resources that have the most favorable

development prospect, which can replace many one-off resources in some uses, The wind

power generating technology is made more and more attentions [1]. Because wind power

plants are mostly in the remote districts, deployed dispersedly, their running state monitor

become difficult. Furthermore, wind energy's random and seasonal characteristic will

possibly cause the electric power system to be unstable. Along with the wind plants’ scale

expansion, the wind power generation also makes more and more unstable influence on

the electric network. The overseas research indicates that if the wind power generation

capacity does not surpass 10% of the electric network's capacity, the wind power

generating system has little effect on the electric network’s operation [2]. Otherwise,

whether the electric power system is safely steadily operating becomes the topic that must

be studied.

SCADA system for the wind plant is the process control and schedule system of wind

power generation. It can realize the automatic surveillance of wind speed, wind direction,

the long-distance online diagnosis and control of wind generator, which provides

safeguard for safe and effective running of wind power plant [3]. Wireless Sensor

Networks (WSN) is a novel distributed data processing system, which is developed with

the advancement of MEMS, sensing, computing and wireless communication

technologies [4, 5]. WSN has the advantage of distributed information processing,

covering broadly, and long-distance monitoring. WSN is applied to the wind power plant

SCADA system in this paper, which can realize the efficient, convenient, reliable

surveillance for the wind power plant.

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CHAPTER 2

WIND FARMS

A wind farm is a group of wind turbines in the same location used for production of electric power. Individual turbines are interconnected with a medium voltage (usually

34.5 kV) power collection system and communications network. At a substation , this

medium-voltage electrical current is increased in voltage with a transformer for

connection to the high voltage transmission system.

A large wind farm may consist of a few dozen to several hundred individual wind

turbines, and cover an extended area of hundreds of square miles, but the land between

the turbines may be used for agricultural or other purposes. A wind farm may be located

off-shore to take advantage of strong winds blowing over the surface of an ocean or lake.

2.1 FACTORS CONSIDERED WHILE DESIGNING WIND FARMS

A. LOCATION

A quantity called the Wind Power Density (WPD) is used to select locations for wind

energy development. The WPD is a calculation relating to the effective force of the wind

at a particular location, frequently expressed in term of the elevation above ground level

over a period of time. It takes into account velocity and mass. Color-coded maps are

prepared for a particular area describing, for example, "Mean Annual Power Density, at

50 Meters." The results of the above calculation are used in an index developed by the

National Renewable Energy Lab and referred to as "NREL CLASS." The larger the WPD

calculation the higher it is rated by class. [5]

Wind farm siting can be highly controversial, particularly when sites are picturesque or

environmentally sensitive. Related factors may include having substantial bird life, or

requiring roads to be built through pristine areas. The areas where wind farms are built

are generally non-residential, due to noise concerns and setback requirements.

Access to the power grid is also a factor. The further from the power grid, the more

transmission lines will be needed to span from the farm directly to the power grid.

Alternatively, transformers will have to be built on the premises, depending upon the

types of turbines being used. [5]

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WIND POWER PLANTB. WIND SPEED

As a general rule, wind generators are practical if wind speed is 10 mph (16 km/h or

4.5 m/s) or greater. An ideal location would have a near constant flow of non-turbulent

wind throughout the year, with a minimum likelihood of sudden powerful bursts of wind.An important factor of turbine siting is also access to local demand

or transmission capacity.Usually sites are preselected on basis of a wind atlas , and

validated with wind measurements. Meteorological wind data alone is usually not

sufficient for accurate siting of a large wind power project. Collection of site specific data

for wind speed and direction is crucial to determining site potential. [6] Local winds are

often monitored for a year or more, and detailed wind maps constructed before wind

generators are installed.To collect wind data, a meteorological tower is installed with instruments at various

heights along the tower. All towers include anemometers to determine the wind speed and

wind vanes to determine the direction. The towers generally vary in height from 30 to

60 meters. The towers primarily are guyed steel-pipe structures which are used for one to

two years to collect data and then are disassembled and removed. Data is collected by a

data-logging device, which stores and transmits data for analysis. The siting of turbines

during installation (a process known as micro-siting) because differences of 30 m cannearly double energy production. For smaller installations where such data collection is

too expensive or time consuming, the normal way that developers prospect for wind-

power sites is to look for trees or vegetation that are permanently "cast" or deformed by

the prevailing winds. Another way is to use a wind-speed survey map or historical data

from a nearby meteorological station, although these methods are less reliable.

ALTITUDEThe wind blows faster at higher altitudes because of the reduced influence of drag. The

increase in velocity with altitude is most dramatic near the surface and is affected by

topography, surface roughness, and upwind obstacles such as trees or buildings.

Typically, the increase of wind speeds with increasing height follows a wind profile

power law , which predicts that wind speed rises proportionally to the seventh root of

altitude. Doubling the altitude of a turbine, then, increases the expected wind speeds by

10% and the expected power by 34%.

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WIND POWER PLANTWIND POWER EFFECT

The "wind park effect" refers to the loss of output due to mutual interference among

turbines. Wind farms have many turbines, and each extracts some of the energy of the

wind. Where land area is sufficient, turbines are spaced three to five rotor diameters apart perpendicular to the prevailing wind, and five to ten rotor diameters apart in the direction

of the prevailing wind, to minimize efficiency loss. The loss can be as low as 2% of the

combined "nameplate" rating of the turbines.

In a large wind park, due to "multifractal" effects among individual rotors, the behavior

deviates significantly from Kolmogorov 's turbulence scaling for individual turbines.

2.2 HOW A WIND POWER TURBINE WORKS

The wind turbine converts the wind’s kinetic energy into electricity. A wind turbine

works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind

turbines use wind to make electricity. The wind turns the blades, which spin a shaft,

which connects to a generator and makes electricity.

2.3 TURBINESThe hub and blades of the wind power unit, or aero generator, are called the turbine (or

rotor). Behind the turbine in the nacelle (engine house) is the rest of the electrical

equipment and machinery (see sketch with cross-section). The nacelle is mounted on a

tower in order to allow the wind to flow freely through the turbine, and because the speed

of the wind increases considerably with the height above ground. In the vast majority of

wind power turbines the nacelle contains a yawing gear system, which ensures that the

turbine automatically faces into the wind. The blades slow the wind down and recover

part of its kinetic energy. The turbine on the wind power turbines at Horns Rev 1 (Horns

Reef Offshore Wind Park 1) is 80 meters in diameter with a slewing area or sweep of

5,024 sq.m, in other words the size of a football pitch. The mass of air sweeping through

the slewing area every second at a wind speed of 10 m/s amounts to about 70 tones.

That’s the equivalent of two fully loaded tankers.

The blades are made from composite material, which makes for a durable design. The

turbine blades have an integral, sophisticated lightning protection system, which offers

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WIND POWER PLANT protection from damage caused by strokes of lightning. The weight on the blades is

typically more than 10 tones. Most towers are manufactured from steel, with a height of

60-100 meters. Their weight varies from 125 to 200 tones. However, even larger turbine

towers and blades are”in the pipeline”.

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WIND POWER PLANTFigure 1: Inside of Wind Turbine

2.4 EXPLOITING THE WIND

As the wind blows, it creates a pressure difference in front of and behind the blades,

causing the blades – and the turbine axle or shaft – to rotate. The turbine axle drives a

generator, which generates electricity. The generator is located in the housing on the top

of the tower, and the electricity is transmitted to the power grid via cables. The principle

of a wind power turbine is remarkably similar to an old-fashioned bicycle dynamo.

2.5 THE GENERATOR

The shaft of the turbine is connected to a generator located inside the wind power

turbine’s engine house. Between the turbine and the generator there is normally a gear,

which converts the turbine’s low speed of e.g. 6-16 revolutions per minute (r.p.m.) to the

generator’s 1,500 r.p.m. The generator produces electricity, which is distributed through

the national grid.

2.6 WIND POWER AND GRID

When there is only a slight or no wind, the wind power turbines are ”on hold”, poised and

ready to go. When the wind gets up sufficient speed, approximately 4 m/s, production

starts automatically. At 12-14 m/s the wind power turbine produces its full output. In

powerful winds, when the windspeed exceeds 25 m/s or so, the mechanical stresses are so

great that the wind power turbines automatically stop in order not to cause unnecessary

wear and tear.

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CHAPTER 3

WIRELESS SENSOR NETWORK

A wireless sensor network (WSN) consists of spatially distributed autonomous sensors to

cooperatively monitor physical or environmental conditions, such

as temperature, sound , vibration, pressure, motion or pollutants. The development of

wireless sensor networks was motivated by military applications such as battlefield

surveillance and are now used in many industrial and civilian application areas, including

industrial process monitoring and control, machine health monitoring, environment andhabitat monitoring, healthcare applications, home automation , and traffic control.

In addition to one or more sensors, each node in a sensor network is typically equipped

with a radio transceiver or other wireless communications device, a

small microcontroller , and an energy source, usually a battery . A sensor node might vary

in size from that of a shoebox down to the size of a grain of dust although functioning

"motes" of genuine microscopic dimensions have yet to be created. The cost of sensor

nodes is similarly variable, ranging from hundreds of dollars to a few pennies, depending

on the size of the sensor network and the complexity required of individual sensor

nodes.Size and cost constraints on sensor nodes result in corresponding constraints on

resources such as energy, memory, computational speed and bandwidth.

A sensor network normally constitutes a wireless ad-hoc network, meaning that each

sensor supports a multi- hop routing algorithm where nodes function as forwarders,

relaying data packets to a base station. In computer science and telecommunications,

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WIND POWER PLANTwireless sensor networks are an active research area with numerous workshops and

conferences arranged each year.

Wireless Sensor Networks presents a comprehensive and tightly organized compilation of

chapters that surveys many of the exciting research developments taking place in this

field. Chapters are written by several of the leading researchers exclusively for this book.

Authors address many of the key challenges faced in the design, analysis and deployment

of wireless sensor networks. Included is coverage of low-cost sensor devices equipped

with wireless interfaces, sensor network protocols for large scale sensor networks, data

storage and compression techniques, security architectures and mechanisms, and many

practical applications that relate to use in environmental, military, medical, industrial and

home networks.

Figure 2: Typical Multihop Wireless Sensor Network Architecture

The book is organized into six parts starting with basic concepts and energy efficient

hardware design principles. The second part addresses networking protocols for sensor

networks and describes medium access control, routing and transport protocols. In

addition to networking, data management is an important challenge given the high

volumes of data that are generated by sensor nodes. Part III is on data storage and

manipulation in sensor networks, and part IV deals with security protocols andmechanisms for wireless sensor networks. Sensor network localization systems and

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WIND POWER PLANTnetwork management techniques are covered in Part V. The final part focuses on target

detection and habitat monitoring applications of sensor networks.

3.2 CHARACTERISTIC OF WSN

Unique characteristics of a WSN include:

1. Limited power they can harvest or store

2. Ability to withstand harsh environmental conditions

3. Ability to cope with node failures

4. Mobility of nodes5. Dynamic network topology

6. Communication failures

7. Heterogeneity of nodes

8. Large scale of deployment

9. Unattended operation

10. Node capacity is scalable, only limited by bandwidth of gateway node.

Sensor nodes can be imagined as small computers, extremely basic in terms of their

interfaces and their components. They usually consist of a processing unit with limited

computational power and limited memory, sensors (including specific conditioning

circuitry), a communication device (usually radio transceivers or alternatively optical ),

and a power source usually in the form of a battery. Other possible inclusions are energy

harvesting modules, secondary ASICs , and possibly secondary communication devices(e.g. RS-232 or USB ).

The base stations are one or more distinguished components of the WSN with much more

computational, energy and communication resources. They act as a gateway between

sensor nodes and the end user.

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CHAPTER 4

SCADA SYSTEM

SCADA stands for supervisory control and data acquisition. It generally refers to

industrial control systems: computer systems that monitor and control industrial,

infrastructure, or facility-based processes, as described below:

1. Industrial processes include those of manufacturing , production , power

generation , fabrication , and refining , and may run in continuous, batch, repetitive, or

discrete modes.

2. Infrastructure processes may be public or private, and include water treatment and

distribution, wastewater collection and treatment , oil and gas pipelines, electrical

power transmission and distribution, Wind Farms, civil defense siren systems, and

large communication systems.

3. Facility processes occur both in public facilities and private ones, including

buildings, airports, ships, and space stations. They monitor and control HVAC ,

access, and energy consumption.

4.1 COMMON SYSTEM COMPONENTS

A SCADA's System usually consists of the following subsystems:

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WIND POWER PLANT1. A Human-Machine Interface or HMI is the apparatus which presents process data

to a human operator, and through this, the human operator monitors and controls the

process.

2. A supervisory (computer) system, gathering (acquiring) data on the process andsending commands (control) to the process.

3. Remote Terminal Units (RTUs) connecting to sensors in the process, converting

sensor signals to digital data and sending digital data to the supervisory system.

4. Programmable Logic Controller (PLCs) used as field devices because they are

more economical, versatile, flexible, and configurable than special-purpose RTUs.

5. Communication infrastructure connecting the supervisory system to the Remote

Terminal Units.

4.2 SUPERVISION V/S CONTROL

There is, in several industries, considerable confusion over the differences between

SCADA systems and distributed control systems (DCS). Generally speaking, a SCADA

system always refers to a system that coordinates, but does not control processes in real

time . The discussion on real-time control is muddied somewhat by newer telecommunications technology, enabling reliable, low latency, high speed

communications over wide areas. Most differences between SCADA and DCS are

culturally determined and can usually be ignored. As communication infrastructures with

higher capacity become available, the difference between SCADA and DCS will fade.

4.3 SYSTEM CONCEPTS

The term SCADA usually refers to centralized systems which monitors and controls

entire sites, or complexes of systems spread out over large areas (anything between an

industrial plant and a country). Most control actions are performed automatically

by Remote Terminal Units ("RTUs") or by programmable logic controllers ("PLCs").

Host control functions are usually restricted to basic overriding or supervisory level

intervention. For example, a PLC may control the flow of cooling water through part of

an industrial process, but the SCADA system may allow operators to change the set

points for the flow, and enable alarm conditions, such as loss of flow and high

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WIND POWER PLANTtemperature, to be displayed and recorded. The feedback control loop passes through the

RTU or PLC, while the SCADA system monitors the overall performance of the loop.

Data acquisition begins at the RTU or PLC level and includes meter readings and

equipment status reports that are communicated to SCADA as required. Data is then

compiled and formatted in such a way that a control room operator using the HMI can

make supervisory decisions to adjust or override normal RTU (PLC) controls. Data may

also be fed to a Historian , often built on a commodity Database Management System , to

allow trending and other analytical auditing.

SCADA systems typically implement a distributed database, commonly referred to as

a tag database, which contains data elements called tags or points. A point represents a

single input or output value monitored or controlled by the system. Points can be either

"hard" or "soft". A hard point represents an actual input or output within the system,

while a soft point results from logic and math operations applied to other points. (Most

implementations conceptually remove the distinction by making every property a "soft"

point expression, which may, in the simplest case, equal a single hard point.) Points are

normally stored as value-timestamp pairs: a value, and the timestamp when it was

recorded or calculated. A series of value-timestamp pairs gives the history of that point.

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Figure 3 : SCADA system for Pump and valve system

CHAPTER 5

WIRELESS SENSOR NETWORKS AND WIND FARMS

The use of wind power to generate energy is growing very quickly. However, as we havenoted previously, there are a number of challenges facing wind farms. Wind Turbines are

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WIND POWER PLANTcomplex devices that require frequent maintenance. One possible aid for wind farms may

be wireless sensor networks (WSNs) which can be used for predictive and monitoring

purposes.

The key value of wireless sensor networks (WSNs) is their ability to collect data in real-

time from physical environments that are often hard to monitor. This data can then be

correlated to ascertain trends and product information for analysis and decision making.

One way in which WSNs could assist wind farms is in the problem of wind power

prediction. The power generated by wind turbines is contingent upon wind speed. Sensor

motes can be easily integrated with a wind speed meter (sometimes referred to as an

anemometer) to provide real-time data on the wind speed in a wind farm location. This

data can then be transformed into information and correlated with historical data on the

power generated by a particular wind turbine given that wind speed. Such cumulative

information for all the turbines in a wind farm can then be used to predict the power

generated by that farm for a particular period. Since the power generated by a farm is

ultimately sold to an electricity utility, this information can be used to predict revenue for

the organisation for a particular period. Such a solution would be low cost and, given the

nature of WSNs, easy to deploy.

In addition to its role in predicting power and revenue generation, wind speed can also be

used for operational purposes, for example, to determine the correct blade rotation for the

turbine. WSNs can also be used to measure vibrations within the turbine equipment to

determine the prospect of failure and prevent unnecessary downtime. Given the

requirement for 2 weeks scheduled maintenance mandated by many turbine vendors this

is a key issue. WSNs can be used for condition monitoring generally. Condition

monitoring offers significant value to a wind farm operator as the cost of downtime is

significant not only in terms of equipment repair but also in terms of lost revenue. This

issue is further exaceberated by the fact that wind farms are often in locations such as

mountains and hills that are hard to access. Indeed, offshore wind farms are becoming

more prevalent. The diagnosis by sensor motes of impending failures can result in a

number of actions. Sensors embedded within a turbine could interact with the equipment

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WIND POWER PLANTto take a number of actions such as the scheduling of maintenance, the reconfiguration of

certain operations or the emergency shutdown of the equipment.

In addition to measuring wind speed, WSNs can be used to measure other characteristics

of the physical environment including temperature, humidity, rainfall and light. WSNs

can also be used to provide identifications for individual turbines and farms and their data

can be fused with Web 2.0 presentation technologies to provide real-time identification of

a wind farm, its turbines and the conditions of same. Using 3G, broadband, wireless or

satellite communications, data can be transferred from the remote locations in which wind

farms typically reside.

The Vertoda Framework can capture data from WSNs and transform this data intomeaningful and timely information. Using this information, wind farms can reduce

maintenance costs, improve operational efficiencies and more accurately measure their

revenues.

5.1 SCADA SYSTEM FOR WIND POWER PLANT

Wind energy is the low density energy, and has the instability and the random

characteristic [6]. So, we must use the wind power resource fully, improve the wind

energy usage efficiency, safeguard the wind generator output nearby the rated value,

reduces the output fluctuation, realize the wind power plant running efficiently and

economically. SCADA in the wind power system, can guarantee system information

integrality, grasp the wind power systems’ operation condition exactly, quicken the

increase production and the maintenance decision-making, enhance production efficiency,

and help correctly diagnoses the system failure condition fast[7,8]. Considering the wind

power plant special demands, the SCADA system should have many functions, such as

data acquisition and processing, systems control and adjustment, the operational factors

count and production management, safe operation surveillance and fault warning and

system fault diagnosis and redundancy cut[9,10]. Furthermore, it can compute the total

power of wind generators, transmitted power loss analysis. We can forecast wind power

generation overall output tendency by the real-time data computation, and arrange the

production plan correctly.

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CHAPTER 6

WSN ARCHITECTURE OF WIND POWER PLANT

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WIND POWER PLANTWireless Sensor Networks (WSN) is a novel technology, which is developed with the

advancement of micro-electronic, data processing, computing, and wireless

communication technology[11,12]. The main goal of WSN is to perform distributed

sensing tasks especially for applications such as environmental monitoring, smart spaces,medical systems and etc. WSN is made up of a large number of sensor nodes, which

consist of sensor, data processing, power provision and communicating modules[13]. The

node architecture is shown in Fig.1.

Figure 4 : Node Architecture of Wireless Sensor Network

The sensor nodes, which are capable of sensing, processing, wireless communication, are

deployed in the sensor field, picking up detecting data by all kinds of sensors, processing

in the data processing module, and transmitting data to the sink node, then to monitor

center for multi-users. The network architecture is shown in Fig.2. Though the individual

node has limited capabilities, WSN which typically has hundreds to thousands of nodes is

capable of achieving a large task through the cooperation of these nodes[14]. As a

distributed information processing system, WSN has much merits, such as credible

measure precision, wider coverage, and remote control. It has become one of the research

hotspots now.

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WIND POWER PLANTThe function of data gathering, processing, and wireless communication, is integrated in

the tiny node. When sensor nodes are deployed in the detecting areas, according to the

certain route algorithm, detecting data are transmitted from sensor nodes to the sink node

through multi-hop wireless communication.

Figure 5: Architecture of Wireless Sensor Network

CHAPTER 7

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WIND POWER PLANTWSN Architecture of SCADA for Wind Power Plant

In SCADA system based on WSN in wind power plant, nodes is composed of sensor

nodes and sink node (as shown in Fig.3). Sensor nodes are deployed on the top of wind

power generator, and they have many sensors, which gather monitoring information, such

as the wind velocity, direction, and the generator running status. The information of wind

power plant detected by sensor nodes is disposed simply, then transmitted to sink node

through wireless multhop communication. Finally, sink node transmits the information to

surveillance center through Internet or satellite.

7.1 Node Design of WSN

Nodes of WSN comprise sensor node and sink node. Sensor nodes can gather and

transmit data to sink node through wireless communication. Sensor node is composed of

sensing module, processing module, communication module, and power module. Fig.

Figure 6: WSN structure of SCADA for wind power plant

Considering sensor node cost, resource requirement and communication reliability, we

adopt Philips Corporation’s 8 bit 80C51 micro controller P89V51RD2FBC as the

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WIND POWER PLANTInternet. The hardware of sink node is mainly made of the central processing unit, storage

unit, the radio frequency transceiving module and GSM wireless communication module.

The structure of sink node is as shown in Fig.5.

Figure 8: Structure of Sink Node

Considering the function, performance request of sink node, such as high end application,

handling ability, node cost, network communication protocol and operating system, we

select ATMEL Corporation’s 32 bit AT91FR40162 as the processor. It has low power

loss, and multi peripheral interface. Its Ethernet connection is constituted by the CS8900

network card . In order to receive the data from senor nodes, the sink node also has the

same transceiving module, nRF401, as the sensor node.

CHAPTER 8WIRELESS COMMUNICATION PROTOCOL DESIGN

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8.1 Wireless Communication Route Algorithm

Sensor nodes, located on the top of wind power generator, not only gather the real-time

information of wind power generators, but transmit data to the sink node. In WirelessSensor Network, excessive use of node to transmit can makenode energy consume

quickly, shorten network lifetime and cause communication congestion, which affect the

reliability of the SCADA system. In order to balance node energy consumption, we select

route node according to its energy consumption, which reduces the usage frequency of

routes, balances nodes’ energy consumption, prolongs the lifetime of WSN. In this paper,

we adopt IDD-PC based on energy comparison to transmit detecting data, according to

distance between nodes, node energy consumption, which consults the shortest routealgorithm in the 15th reference paper [15]. IDD-PC (Improved Directed Diffusion on

Power Compare), is the route algorithm which improves the directed diffuse algorithm. It

sets up the route from sensor node to sink node according to distance and energy

consumption.

IDD-PC Algorithm as follows:

Step.1: Sink node floods the detecting task to all sensor nodes N(i)(i=1,2,……,n).

Step.2: Each sensor node sets up its superior neighboring nodes’ energy information

table. It is shown in table I as follows.

Table 1 : Energy Information of Superior Neighboring Node

NID(i) denotes the superior neighboring nodes of node i,

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WIND POWER PLANTREI(i,j) denotes the remainder energy of its superior neighboring node j, L(i,j) denotes the

distance between node I and node j.

Step.3: Route setup. Suppose time threshold is T, and distance threshold is L=VT, V isthe electromagnetic wave transmission speed. When node i is a route node, we select the

node that the remainder energy is most among its neighboring nodes as its next route

node, that is j=arg max{ SRI(i,j)}. As shown in Fig.6. Firstly, the sink node floods the

task to all sensor nodes, as shown in Fig.6 (a). Then, each node set up its remainder

energy information table. Secondly, the optimal route is set up from source nodes to sink

node according to distance and remainder energy. As shown in Fig.6(b), in time t,

regarding node 14, if L(12,14)<VT , L(13,14)<VT , L(i,j) denotes the distance betweennode i and node j. Either node 12 or node 13 is selected as the next route node, which has

the most remainder energy. Here suppose REI(14,12) < REI(14,13) so node 13 is the

next route node of node 14. Likewise, other sensor nodes select their optimal neighboring

nodes as their next route nodes.

Here, at time t, the optimal route:

8->4->1->S , 12->9->5->2->S , 14->13->10->6->3->S , 11->7->3->S.

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(a) Task Diffuse of Sink Node

(b) Setp of Transmission Route

Figure 9: Route Scheme on IDD-PC

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WIND POWER PLANT8.2 Node Software Design

The software design of WSN includes sensor node and sink node software design.

1) Sensor Node Software Design: Assembly and C# is adopted as the main developmentlanguages in sensor node software design. The main function of sensor nodes is detecting

wind driven generator running information, such as wind speed, wind direction,

transferred electric power information and etc. The software comprises running status

detecting module, wireless route setup module and wireless communication module.

Software flow chart of sensor node is in Fig.7.

2) Sink Node Software Design: The sink node software mainly completes the function of

receiving data which the sensor nodes transmit, and then transmit to the monitoring center

after processing. Considering the sink node must carry out the massive real-time data

processing, complex TCP/IP task scheduling and the management demand, the embedded

operating system uses multi-duty real-time kernel uC/OS-II , which source code is

transplantable, public and may cut out . The major part source code is compiled with

ANSI C. The software code has not high request for the processor and resources,has good

readable and transplantable performance. As the open characteristic of uC/OS- , the

user is easy to develop their own application programme on uC/OS- , which is suitable

for the network application and the small embedded system's development specially.

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Figure 10: Software Flowchart of Sensor Node

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When the operating system C/OS- is transplanted to the processor of AT91FR40162,

the chip driven program, TCP/IP protocol stack and Ethernet interface are developed

based on the C/OS- , accord to the application demand. The master routine of sink

node mainly contain task processing module, time processing module, memory

processing module , data processing and correspondence module, CPU interface and

other modules. The main software flow chart is shown in Fig.8 as follows. Fig.8. Main

software flow chart of Sink node

Figure 11: Main Software Flowchart of Sink Node

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CHAPTER 9

THE ENERGY OF WSN FORWIND POWER PLANTThe energy consumption of wireless communication is in proportion to [17], k is relate to

transmission data quantity, d is the distance between transmission nodes. The distance

between sensor nodes is several dozen meters to over a hundred meters, so the quantity of

real-time data transmitted is great, and the energy consumption for data transmission is

great. Moreover, because the selected chance of node for router is not equal, some nodes

perhaps consume much more energy, which would brought about unbalance of energy

consumption, result in the shorten of network lifetime.kd n (2 ≤ n ≤ 4)

Considering energy advantage of wind power plant, we adopt the method that the power

is complemented by drawn from the wind driven generator. The sensor node carries the

rechargeable battery, when energy insufficiency, it charges by itself from the wind driven

generator when the generator is running, which could ensure node sufficient power

provision, and the steady operation of the wireless sensor networks.

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