Abstract: A method for obtaining an estimate for a process quantity of a turbomachine comprises measuring (301) first process quantities and calculating (302) an estimate for a second process quantity, for example mass flow, on the basis of the measured first process quantities and a reference table of interrelations between process quantities prevailing in reference inlet conditions corresponding to a pre-defined inlet fluid temperature, a pre-defined inlet fluid pressure, and pre-defined fluid properties at the inlet. The reference table and the measured first process quantities represent such a set of data values that the estimate is obtainable on the basis of different sub-sets of the data values. Hence, the estimation task is over-posed in the sense that there is more data than necessary for obtaining the estimate. In the calculation of the estimate, more weight is given to such a part of the data which has a smaller error contribution.

Abstract: An electric machine comprising a stator having a stator winding, a housing accommodating the stator, a rotor, and an air gap having a generally cylindrical configuration. A plurality of circumferentially distributed, radial, first cooling gas ducts are provided in a stator core. Jets of cooling gas are directed to regions of an end winding which are relatively distant from the stator core, in order to achieve impingement cooling thereof. Flows of cooling gas are directed to portions of the end winding which are between the impingement cooled regions of the end winding and the respective front face of the stator core.

Abstract: A method for obtaining an estimate for a process quantity of a turbomachine comprises measuring (301) first process quantities and calculating (302) an estimate for a second process quantity, for example mass flow, on the basis of the measured first process quantities and a reference table of interrelations between process quantities prevailing in reference inlet conditions corresponding to a pre-defined inlet fluid temperature, a pre-defined inlet fluid pressure, and pre-defined fluid properties at the inlet. The reference table and the measured first process quantities represent such a set of data values that the estimate is obtainable on the basis of different sub-sets of the data values. Hence, the estimation task is over-posed in the sense that there is more data than necessary for obtaining the estimate. In the calculation of the estimate, more weight is given to such a part of the data which has a smaller error contribution.

Abstract: An electric machine comprising a stator having a stator winding, a housing accommodating the stator, a rotor, and an air gap having a generally cylindrical configuration. A plurality of circumferentially distributed, radial, first cooling gas ducts are provided in a stator core. Jets of cooling gas are directed to regions of an end winding which are relatively distant from the stator core, in order to achieve impingement cooling thereof. Flows of cooling gas are directed to portions of the end winding which are between the impingement cooled regions of the end winding and the respective front face of the stator core.