Hydrogenerators convert the mechanical energy from the turbine into electrical energy using an excitation system.
ANDRITZ HYDRO generators are characterized by their compact design, high efficiencies, and long lifetime thanks to the use of modern calculation methods and optimized manufacturing procedures and materials.
Depending on the hydropower plant characteristics, the turbine used and the required speed, the following generators are available:
- Vertical shaft generators
- PIT type generators
- Bulb generators
- Special machines
Vertical shaft generators
Vertical shaft generators are coupled to vertical shaft hydro turbines of any size with outputs up to 840 MVA. ANDRITZ HYDRO has leading experience with vertical generators for Francis, Kaplan and Pelton turbines, for the whole range of outputs and speeds. More than 1,800 large generators supplied by ANDRITZ HYDRO are installed or under construction worldwide in over 700 power plants with a total capacity exceeding 130 GW.
Motor-generators are used in pumped storage plants to generate electrical energy and to drive pump turbines. ANDRITZ HYDRO has supplied motor-generators for pumped storage applications up to 360 MVA with constant or variable speed and one or two directions of rotation, and also has experience with all unit configurations, for example fixed coupling to reversible pump turbines or to a turbine-plus-pump set. The unit can be started with static frequency converters (SFC), pony motor, back-to-back, or a turbine. ANDRITZ HYDRO has special experience in variable-speed motor-generators for optimum efficiency at variable heads and for maximum grid benefits.
PIT type generators
PIT type generators are used for smaller, low-head applications and are coupled via step-up gear to the horizontal turbine shaft. For low-head hydropower stations with lower ratings, pit applications are an economical solution, typically up to 17 MVA and with 500 to 900 rpm. PIT generators stand for robust design and cope reliably with the high runaway speeds required for hydropower plants.
Using the pit liner for generator cooling.
ANDRITZ HYDRO offers generators for the following applications:
- Single-phase generators
- Variable speed motor-generators (Reference Goldisthal PSPP with unit output of 380 MVA)
- Converter stations with asynchronous motor and synchronous single-phase generator for railway systems (16 2/3 Hz)
- Diesel generators
- Permanent magnetic pole generators for Straflomatrix, Hydromatrix and Ecobulb units