The modern power industry is characterized by intense development of distributed generation, with which numerous sources of different capacities are connected into a single network. This makes it possible to improve the reliability of the entire system, since the probability of several sources to fail simultaneously is quite low. Electric generation based on high-speed gas turbine units accounts for a significant share in the overall balance, due to which scientific research and new engineering solutions in this area are important and relevant. An innovative design of a high-speed gas turbine unit based on a switched axial generator is proposed. This electrical machine has a diamagnetic armature, which eliminates magnetic losses, due to which better efficiency of the power unit is achieved and its design is simplified. The high speed of rotation and the presence of critical resonant rotor speeds generated the need to adopt appropriate engineering decisions in regard of its supports. A combined suspension involving the use of magnetic and gas-dynamic bearings is proposed. The magnetic bearings support the gas turbine unit operation at low speeds during its acceleration, and the gas-dynamic bearings support its operation at high nominal speed. The generator design and the combined suspension layout are shown. The numerical analyses of magnetic and gas-dynamic bearings for a gas turbine unit for a capacity of 100 kW and rotation speed of 70 000 rpm are given. The study results can be used for a series of gas turbine units with capacities ranging from 10 to 500 kW. In our opinion, this concept is competitive with modern analogs with a radial generator design.
The first operation results of the gas turbine unit M701F4 as a part of CCP-410 of the Krasnodar TPP after major overhaul
