Construction and technology for synchronous generators with permanent magnets of the new generation
In 2022, the company TES VSETÍN s.r.o. successfully completed a three-year research and development project focused on permanent magnet synchronous generators. The project was implemented in cooperation with the University of West Bohemia in Pilsen Project was supported by the subsidy program TREND 1 of the Ministry of Industry and Trade, provided by the Technology Agency of the Czech Republic.
The project’s main goal was to gain the necessary experience with the design and production of synchronous generators with permanent magnets and thus increase the company’s competitiveness in this segment of electric machines in the domestic and foreign markets.
The main result of the project was a prototype of a synchronous generator with permanent magnets with an axial height of 500mm, an output of 2300kW, and a speed of 1600rpm. The prototype was specially designed for wind power plants, it has a horizontal shape with a rotor mounted on rolling bearings. The machine is cooled using a closed-water cooling circuit, which is supplemented by an internal cooling air circulation system. The combination of these two cooling systems provides efficient cooling of losses occurring in the machine. The magnetic circuit of the stator is made of electrotechnical sheets, which have very low specific losses. The rotor of the machine is composed of magnets glued to the surface of the rotor yoke. Mechanical strength is ensured by a sufficient bandage. The magnets are axially and radially segmented, which resulted in a maximum reduction of losses arising in their material. The rotor is also equipped with temperature sensors enabling online monitoring of the temperature of the rotor parts. A battery-free signal transmission system from the rotor temperature sensors to a PC was developed as part of the project for the possibility of online temperature monitoring. The system also enables the connection of sensors of the stator parts of the generator, so that one system is able to monitor the temperature status of the entire generator. The generator is also equipped with sensors for measuring the flow and temperature of the cooling water.
The parameters of the generator were successfully verified at the electrical machine testing facility of TES VSETÍN s.r.o. Based on the results, it can be stated that both the generator prototype and the electronics system for wireless data transmission met all expectations. The results of the project will contribute to the expansion of know-how in the field of machines with permanent magnets and will support the competitiveness of the company in this segment of machines.
