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AssigneeABB AB
InventorsBertil Berggren, Mons Holleland, Mats Leijon, Maria Lundmark, Ole-Morten Midtgard, Bengt Rothman, Eivind Sande, Marco Sipi, Roald Sporild, Kirsti S Svensen
Estimating the term…
For a method of operating of a synchronous compensator comprising a rotating electric machine comprising rotor (46) and stator (2) with at least one winding with a solid insulation enclosing the electric field, relevant parameters for the temperature conditions in the rotor are determined, and during over-excited operation in order to temporarily enlarge the field of operation of the synchronous compensator, the cooling of the rotor is forced depending on a rotor temperature value (TR) determined from said parameters. Such a synchronous compensator comprises measuring means for measuring parameters relevant for the temperature conditions of the rotor. Means (36, 38) are also provided to force the cooling of the rotor (46) depending on rotor temperature values (TR) determined from said parameters during over-excited operation of the electric machine.
Method of operation of a synchronous compensator comprising a rotating electric machine comprising rotor and stator with at least one winding with solid insulation enclosing the electric field, characterized in that, to temporarily enlarge the range of operation of the synchronous compensator, parameters relevant for the temperature conditions in the rotor are determined and in that at over-excited operation the cooling of the rotor is forced depending on the magnitude of a rotor temperature value (TR) determined from said parameters.
Method according to any preceding claim, characterized by the machine being designed for large short-circuit power.
Method according to any of the preceding claims, characterized in that the cooling is forced by lowering of the temperature of the cooling medium.
Method according to any of the preceding claims, characterized in that the cooling is forced by increasing the flow of cooling medium.
Method according to any of the preceding claims, characterized by the rotor temperature value (TR) being determined from one or more of the parameters inductor current, inductor voltage, temperature directly measured on the rotor, rotor cooling medium temperature and cooling medium flow velocity.
Method according to any of the preceding claims, characterized by controlling the forced cooling at the actual overload so that the rotor temperature value will be equal to or slightly below the maximum allowable rotor temperature.
Synchronous compensator comprising a rotating electric machine with at least one windind with solid insulation enclosing the electric field and with measuring means for measuring of parameters relevant for the temperature conditions in the rotor, characterized by means to force the cooling of the rotor depending of the value of a rotor temperature value (TR) determined from said parameters during over-excited operation of the electric machine.
Synchronous compensator according to any of claime 10-12, characterized by said means being arranged to force the cooling by increasing the flow of cooling medium.
Dependencies are inferred from the claim text.