Tsakiya ce kungiyar muhimmiyar turbin tsakiyar kasa wanda ke taimakawa masu kungiyoyi. Tana taimaka turbin da kuma yin shi zuwa gaba ta da kyau don haka zai kasance da kasa a lokacin da ya kawo. Ba haka ba, muna bukata cewa tsakiya yana da kasa, don haka za ta samu kasa mai kyau. Kasa na tsakiya yana da shiga da fadada turbini. Tsakiya na turbini a makarantar sana'ar kasa na tsakiya yana daga 40 mita zuwa 100 mita. Wannan tsakiyan na iya zama tsakiya na kasa, ko tsakiya na tubular steel, ko tsakiya na beton. A tunanin turbini mai yawa, ana amfani da tsakiya na tubular steel. Waɗannan suna rawa a kasa da tsakiya da suka sauransu daga 30 zuwa 40 mita.
Kasuwanci na tsakiya suna da flanges da holes. Wannan kasuwanci suna daɗe da nut bolts a wurin da take formi tsakiya daidai. Tsakiya daidai yana da shape mai kasa don bayyana mechanical stability. Ana amfani da tsakiya na lattice da different members of steel ko GI angles ko tubes. Duk member suna daɗe da bolted ko welded together don formi tsakiya daidai da kasa da ma'adan. Cost na waɗannan tsakiyan yana da damuwa ciki da cost na tubular steel tower, amma ba yanzu ba ake amfani da ita saboda look na. Transportation, assembling, and maintenance suna da karfi, amma ba a yi amfani da ita a wurin da ake yi aikin turbini saboda look na. Akwai kungiyar tsakiya na biyu wanda ake amfani da ita a turbini mai kasa, wannan shi ne guyed pole tower. Guyed pole tower yana da single vertical pole supported by guy wired from different sides. Saboda number of guy wires, ita ce zai fi karfi a tafi kan footing area of the tower. Saboda haka, muna bukata cewa ba a yi amfani da wannan kungiya a agricultural field ba.
Akawo akwai kungiyar tsakiya na biyu wanda ake amfani da ita a small plant, wannan shi ne hybrid type tower. Hybrid type tower yana da guyed type tower, amma farkon da ke cika shi ce instead of using a single pole in the middle it uses a thin and tall lattice type tower. Hybrid type tower yana da hybrid of both lattice type and guyed type tower.
Nacelle yana da box ko kiosk mai yawa wanda ke jirga a tsakiya da ke taimaka masu components of a wind turbine. It houses an electrical generator, power converter, gearbox, turbine controller, cables, a yaw drive.
Blades yana da kungiyar muhimmiyar a turbin tsakiyar kasa. Blades yana convert wind energy into usable mechanical energy. Idan kasa yana fitowa blades, blades yana kawo. Wannan kawo yana taimaka mechanical energy to the shaft. Ana design blades like airplane wings. Wind turbine blades can be 40 meters to 90 meters long. Blades yana da kyau a taimaka strong wind even during the storm. Amma, blades yana da kyau a taimaka light as possible to facilitate smooth rotation of the blades. Don haka, ana make the blades with fiberglass and carbon fiber layers on synthetic reinforce.
In a modern turbine, normally three identical blades are fitted to a central hub using nut bolts. Each identical blades are aligned at 120o to each other. The process makes a better distribution of mass and gives the system more smooth rotation.
Shaft directly connected to the hub is a low-speed shaft. When the blades rotate, this shaft spins with the same rpm as the rotating hub. We couple this shaft directly to the electrical generator in case of a low-speed generator. But in most cases, the low-speed main shaft is geared with a high-speed shaft through a gearbox. In this way, the rotor blades transfer its mechanical energy to the shaft which ultimately enters into an electrical generator.
Turbin tsakiyar kasa ba yana kawo da kyau bane yana kawo da kasa. Amma duk generators mai electricity suna buƙatar kawo da kyau, don generate electricity at a desired voltage level. Don haka, muna bukata cewa ake buƙace speed multiplication arrangement to achieve the high speed of the generator shaft. Gearbox na turbin tsakiyar kasa yana yi wannan. Gearbox increases the speed to much higher value. For example, if the gearbox ratio is 1:80 and if the rpm of a low-speed main shaft is 15, the gearbox will increase the speed of generator shaft to 15 × 80 = 1200 rpm.
Generator yana da device mai electricity wanda ke convert mechanical energy received from the shaft into electrical energy. Normally, we use induction generators in modern wind turbines. Previously, synchronous generators were popular for this purpose. Permanent Magnet DC generator also used in some wind turbines. The speed of the shaft can be made high by using gearbox assembly, but we can not make the shaft speed constant. There may be a fluctuation in shaft speed since it depends on wind speed. So, the speed of the rotor also varies. This variation affects the frequency, voltage of the generated electric power. To, overcome these issues, we normally use an induction generator for the purpose.
Because the induction generator always produces electric power synchronized to the connected grid irrespective of the speed of the rotor. If we use the three-phase synchronous generator, then we first rectify the output power to DC and then convert it to AC of desired voltage and frequency using inverter circuit. Because the alternating power generated by the synchronous generator is not constant in voltage and frequency, rather it varies with speed of the rotor. Because, for the same reason, in some cases, we use a DC generator for the purpose. In these cases, the output DC power from generator inverted to AC of desired voltage and frequency, before feeding it to the grid.
Because wind is not always constant, so electrical potential generated from a generator is not constant, but we need a very stable voltage to feed the grid. A power converter is an electrical device that stabilizes the alternating output voltage transferred to the grid.
Turbine controller is a computer (PLC) that controls the entire turbine. It starts and stops the turbine and runs self diagnostic in case of any error
