Recently, the world’s first 2.7MW high-efficiency compact tandem wind turbine “Sairui” has successfully completed hoisting at Huaneng Jilin Tongyu Wind Farm, and will soon enter the demonstration stage of complete machine operation.
The 2.7MW double-rotor permanent magnet synchronous wind turbine is a double-shaft extension double-rotor permanent magnet synchronous generator, which is independently driven by the transmission system at both ends of the machine. The outer rotor generator and the inner rotor generator are coupled into one body through a special structure. High power density, compact structure, and so on.
During the research and development process, the layout of the main structure of the generator became a major difficulty. The motor has a double-rotor structure, which requires two independent stator-rotor systems, cooling systems, bearing structures and stator leads to be arranged in a limited space, which is more complicated than traditional models. In order to overcome this bottleneck, the project team carried out innovative designs in the aspects of the electromagnetic scheme, magnetic field coupling, motor structure, bearing structure, cooling method, etc., and successfully completed the product design after multiple reviews.
Compared with conventional motors, the end of the outer stator coil of the 2.7MW dual-rotor permanent magnet synchronous wind turbine shrinks inward, which increases the difficulty of embedding wires and the risk of insulation damage. After adjusting the coil size and embedding operation method for many times, the method of enlarging the pitch of the stator coil and embedding it is finally adopted to ensure that the size of each coil end is consistent and the insulation is not damaged. Through the joint efforts of the team, the 2.7MW dual-rotor permanent magnet synchronous wind turbine was delivered on schedule.
The “Serui” double-wind turbine wind turbine belongs to the national key research and development plan “Key Technology Research on New High-efficiency Wind Energy Conversion Devices”. Compared with traditional wind turbines, “Serui” uses the front and rear wind wheels to jointly capture wind energy. Under the same power, the blade length is shortened by nearly half, and the cost is reduced by more than 10%. The application prospect is very broad.