A short summary of power production in wind power plant:
The Wind Power Plant works on the basis of wind movement. The wind power plant consists of a tower in which the generator is placed at the top. The generator is coupled to the wind blade through a shaft mechanism. The Wind blade rotate depending on the wind movement. The Generator will convert mechanical energy (Wind blade movement) into Electrical energy and hence the power production is done. This was the basic thing happening in wind energy conversion system.
The components involved in Wind Energy Conversion System:
1. Wind Turbine or Wind Mill:
A Wind Turbine is a one which converts the kinetic energy of the wind to the mechanical energy. The various components of the wind turbine are as follows.
The Nacelle consists of a gearbox, low-speed and high-speed shafts, generator controller and a Brake. It is kept at the top of the tower and also connected to the rotor.
The Rotor consists of a central hub and wind blades. The blades can be of different numbers but mostly three blade wind blades are used in practice. They are manufactured from Fibreglass-Reinforced Polyester (FRP), Steel or Aluminium. The axis can be of Vertical or Horizontal.
Hub and Shaft:
The Hub and Shaft are coupled to the rotor of the wind turbine. The Hub faces the wind direction and is in the front portion.
The Anemometer is a device for measuring the speed. The Gear Box is used to increase or decrease the speed.
2. Transmission Systems:
The power generated by the generator is transmitted to through transmission lines. The Power output is determined by the speed of the turbine. In order to boost the speed gearbox is used. Typically, a gearbox would convert 20 rpm to 50 rpm or from 1000 rpm to 1500 rpm. A step-up transformer is used as the sending end and a step-down transformer is used at the receiving end to reduce the loss which occurs in transmission.
3. Electric Generator:
The wing turbines driving generator can operate in two modes, Constant speed or Variable speed operation. In the variable speed operation, the speed of the rotor varies with wind whereas, in constant speed operation, the speed of the rotor remains constant. The generator used can be of Asynchronous type (Induction) or Synchronous type. Mostly the Induction generators are used for grid-connected operation but the drawback is they draw reactive power from the grid system. In case of a synchronous generator, they do not require reactive power.
4. Yaw Control System:
The yaw control system controls the angle of rotation of nacelle. The Yaw control system is essential so that the wind turbine would face as per the wind direction. The Yaw control is essential for an effective output.
The excess power developed can be stored in a lead-acid battery and it can be used later during demand. It can also be compensated by pumping water and it can be distributed to nearby areas. The main drawback of storing in a lead-acid battery is a certain amount of power is wasted during conversion operation.
6. Energy Converters:
The electricity produced by Wind energy is usually Direct Current (DC). In order to connect with transmission grid, it should be converted to Alternating Current (AC) with the help of alternator.
The Wind Turbines with its utilities are kept at the top of the tower. The Towers can be made up of tubular steels. The Foundation of a tower is much important and it should be mounted with a proper foundation. The maximum height of the tower can be 75 meters. The towers should be designed in such a way that it should withstand the certain weight.
Advantages of Wind Power Plant:
→ Pollution free method of power generation.
→ Renewable source of power generation.
→ Easy to install within a short span of time.
→ Highly economical.
→ Less Installation Cost when compared to other methods.
Disadvantages of Wind Power Plant:
→ The Power generation depends on the wind.
→ Not suitable for peak load demand.
→ Highly affects flora and fauna.
→ Need frequent maintenance and the cost of maintenance is also high.
→ Noise produced is unpleasant.