Advantages:
Dual power supply: Dual power motor has low cost and mature technology; the capacity required by the power electronic conversion device is small, it can be used in small capacity cases; /p>
Fully air-cooled;
Direct drive: can produce electricity over a very wide range of wind speeds; eliminating the need for 1:80 three-stage planetary gearbox, high reliability and good quality; maintenance
; The electronic power conversion device does not require an active crowbar; the power factor is almost unlimited and can be considered as a reactive power generator hooked to the power grid.
Disadvantages:
Dual power supply: the wind speed range required for power generation is too high, typically between +20% and 20% of synchronous speed. Production capacityenergy
is limited. and easy to get off the grid. Economical power generation And stability is very poor; there is a three-stage planetary reducer, which needs to be replaced once every 5 years.
The maintenance cost is very high. (this thing is on a tower, think about maintenance more than 70 meters in the sky
p>
Something at the level of a ton); there is Active Crowbar, which is technically extremely difficult, and now only ABB in the world can do it; the adaptability of the power grid is low and the power factor is limited, generally it can only reach 0.9
Direct drive: the cost of direct drive motors and electricity electronic devices are high; direct drive motor technology is immature; In order to enable the direct drive motor to produce electricity when the wind speed is very low, the number of stage pairs of the motorur is extremely large, usually more. more than 100 pairs, which makes the motor very large. It can only be cooled by water, which is too troublesome.
Prospects:
p>Double feedback: poor engine economy and stability. power generation and poor power grid adaptability determine that wind power has no future development prospects
Perhaps AC excitation of hydro turbines is its development direction< /p>
p>
Direct drive: It has no fatal flaws and is the dominant technology of the future. In fact, Europe has already shown this trend.
Conclusion:
Direct drive is better than double feed.
Personally, I think the best technology is hybrid direct drive, which uses a small gearbox to increase the speed, which can balance
the duration of gearbox life andsize of the vehicle. engine.
I think Goldwind has a good vision in the wind energy field. It's a good idea to avoid double feedback and do direct training. In addition, Goldwind
started to file patents on permanent magnet motors in 2004, and the configuration is still good.
Grid connection method:
Dual feed: There are two main methods: island grid connection and no-load grid connection. The key is to adjust the rotor excitation to. allow the voltage emitted by the stator
and the network voltage to respect the conditions of connection to the network
Direct drive: it is enough to ensure that the output voltage of the inverter and the grid voltage meet the grid connection conditions