Wind Turbines

Wind Turbines made by KONČAR are completely automatized wind turbines. They are initialled when the wind speed reaches the power designed for their start-up. The wind turbine output power raises with the speed of the wind. Wind turbines reach their nominal power at a certain wind velocity (depending on the wind turbine type). When the wind reaches a speed for which the wind turbine is designed to stop working, blades start to rotate on their axes until they obtain the position in which they put up the lowest resistance to the wind and the wind turbine is under the so-called free-wheeling condition, the condition of free rotation. The nacelle is equipped with a yaw system, turning the nacelle always towards the wind. All nacelle components are installed in a line related to the wind turbine main axis. Besides the nacelle yaw system, the wind turbine also has a generator excitement system, control system, lubrication system, braking system, blade turning system, fire alarming system and a nacelle air-conditioning and heating system. The direct wind turbine operation solution (without a gearbox) has several benefits compared to other possible solutions. Such turbines use more wind power by 10-15 % transforming it into the electric power, decrease mechanical losses and the level of noise, achieve higher operational safety and it is also worthwhile to mention the benefit of a simpler maintenance of those wind turbines.

Wind turbines are designed pursuant IEC Standards and their foreseen operational life time is 20 years.

Each wind turbine is exposed to severe factory quality controls as well as verifications and functional testing at the construction site.

A brief technical description of the main wind turbine components:

WIND TURBINE ROTOR

The Rotor has a console construction including three blades mounted in the direction of the wind. The output power is controlled by a pitch regulation (rotation of blades on their axes). The speed of rotation of the rotor is changeable and designed to increase its aero dynamic efficiency to the maximum.

 

The hub is cast from a nodular cast piece and fixed to the axis sleeve over bearings, while its flange is fixed to the generator rotor. The hub is constructed in such a way to provide for a room necessary for two maintenance technicians for the needs of maintenance the blade root and slewing rings. The axle pin is a cast construction made of a steel cast piece fixed to the generator stator over the flange. Two main bearings are placed on it.

BLADES

Wind turbine blades are made of epoxy raisin enforced with glass fibre, each one consisting of two parts glued together. Blades are mounted on turning points that can theoretically rotate by 360o, but the necessary rotation angle on their axes is from 0 to 90o regulating the power and aero dynamic braking. Each blade has its own independent turning mechanism apt to turn the blade under every operating condition. The pitch operation enables optimization of the output power within the operating area. To decrease the wind load blades can be also turned when the wind power plant does not generate the electric energy. Blades are equipped with a protective lightening system and on their tops marked with a signalling paint.

NACELLE

The nacelle is designed by KONČAR. It is made of glass fibre reinforced plastic bearing the manufacturer title embossed horizontally alongside the middle of the housing. Two roof windows are placed in the upper part of the nacelle. When opened, they enable entrance of light and air into the nacelle. Anemometers  and aviation lights are fixed on the upper housing part. They are easily accessible from the nacelle.  

TOWER

The wind turbine is mounted on a conical steel tube tower. The tower consists of three or more sections depending on its height. A ladder and an electrical elevator are placed within the tower necessary for reaching of the wind turbine nacelle. Platforms and electrical lightening are installed in the tower as well. The tower is equipped with signalling lights.  

PROZA NET SCADA

PROZA NET is a multiuser system intended for monitoring and control of electric energy system operation. PROZA NET SCADA system is developed on that bases and tailored to fulfil the needs and requirements specific for monitoring and control of wind power plants. In addition to the possibilities of group and individual wind turbine control, PROZA NET can analyse process operations in the real and study time. The system is featured by high operating performances and the modular architecture supporting at the same time a high level of outside system integration.

 

 

 

    

 

GENERATOR

The generator represents a synchronous machine having variable rotations per minute cooled by an air flow drifting through the air gap. The air flow is driven by a cooling fan placed in the rear of the nacelle. The fan also comprises a control system operating on the basis of signals coming from the temperature sensor that measures the winding temperature.

WIND TURBINE YAW SYSTEM

The wind turbine yaw system turning the nacelle is composed of a ball bearing with outside serration and four or more electric motor reduction gears.

FREQUENCY CONVERTER

There is a foursquare fluid cooled frequency converter.  

 

MONITORING SYSTEM

The monitoring system is designed to verify and signal all necessary corrections of the wind turbine construction. Installed sensors measure wind turbine stresses, vibrations and temperature and the communication equipment signals conditions of each individual plant component that are also recorded in the data base. The monitoring system points out any possible wind turbine problem even before it exactly occurs reducing in such a way the unplanned maintenance to the minimum, decreasing maintenance costs, increasing wind turbine availability and prolonging the plant operational life time.

 

 

WIND TURBINE TYPES: