Okay. This is linked to the wind resource where the wind turbine is located, as well as the electricity production capacity of the wind turbine itself. If the wind resource is good, for the same generator, the power generation effect will be good. As for the power generation capacity of the generator itself, it is related to the size of the wind blades, the number of metal coils, the amount of magnetic field materials, and the size of the magnetism. Since the blades, metal coils and magnetic materials of small wind turbines are less than those of large generators, the current generated by breaking the magnetic lines of force is less and the electricity generation is low.
What is a semi-direct drive wind turbine? How is this different from direct transmission?
The moment of inertia mainly refers to the power exerted on the hub when the blades rotate. ByTherefore, the moment of inertia is only related to the design of the blade itself and the magnitude of the wind force.
First, it is proportional to the force of the wind; second, it is proportional to the upwind area of the blade surface; thirdly, it is proportional to the maximum value of the power utilization coefficient Cp of the blade Wind force Not to mention the size, the value Cp of the blade, which is the coefficient of power usage, is related to the design of the blade surface (this coefficient has a theoretical upper limit and the current limit is 0.498)
The drive concept semi-direct arose from problems encountered in the development of direct-drive, dual-fed wind turbinesin large-scale production projects. development, taking into account the characteristics of both.
The difference between a driven wind turbineement semi-direct and a direct drive wind turbine:
1. The principles of the two are different,
1. A direct drive wind turbine is a generator directly driven by the wind, also known as a gearless wind turbine. This generator is driven by a multi-pole motor directly connected to the turbine, eliminating the need for a traditional component such as a multi-pole motor. a gearbox.
2. The semi-direct drive wind turbine adopts single-stage or double-stage speed-increasing gearbox, multi-pole synchronous generator and full-capacity converter. In addition, in order to reduce the weight of the machine room, semi-direct drive wind turbines are mostly compact designs, that is, the low-speed shaft is eliminated or the length of The low shaft speed is reduced and the power output is reduced. The speed increase housing shaft is directedectly connected to the main shaft of the generator.
2. The advantages of both are different
1. The direct drive wind turbine has no gearbox, which reduces transmission losses and improves power generation efficiency, especially in low conditions. wind speed environments, the effect is more significant.
2. The semi-direct drive generator rotates at high speed. This feature determines that the semi-direct drive can on the one hand improve the reliability and service life of the gearbox, at the same time as the direct drive generators, it can take into account the corresponding design of the generator and improve design and manufacturing conditions. of high power direct drive generators.
3. The structures of the two are different.
1. Direct drive wind turbine uses a multi-pole motor directly connected to the turbinefor the drive, eliminating the need for a gearbox part. Since the gearbox is a component that is easily overloaded and has a high rate of premature damage in megawatt wind turbines, there is no direct drive wind turbine without a gearbox.
2. The concept of semi-direct drive is a combination of direct drive and dual-powered wind power. It is due to the problems encountered in the development of large-scale units, considering the characteristics of both. Structurally speaking, the semi-direct drive is similar to the double-feed drive and has the characteristics of various configuration forms. At the same time, the pinless structure under current research also has a similar appearance to the direct drive.
The above content refers to Baidu Encyclopedia - Self-Drive Wind Turbinemi-direct
The above content refers to Baidu Encyclopedia - Direct Drive Wind Turbine