Abstract:
A method and system for monitoring the operating conditions of an electric generator. The system includes a triad sensor array formed within a predetermined section of a fiber optic conductor. The triad sensor array is formed of a group of sensors including a first sensor including a Bragg grating for producing a first signal representative of strain in a stator bar of the generator, a second sensor including a Bragg grating for producing a second signal representative of temperature in the stator bar, and a third sensor including a Bragg grating for producing a third signal representative of vibration amplitude in the stator bar.
Abstract:
A method and system for monitoring the operating conditions of an electric generator. The system includes a triad sensor array formed within a predetermined section of a fiber optic conductor. The triad sensor array is formed of a group of sensors including a first sensor including a Bragg grating for producing a first signal representative of strain in a stator bar of the generator, a second sensor including a Bragg grating for producing a second signal representative of temperature in the stator bar, and a third sensor including a Bragg grating for producing a third signal representative of vibration amplitude in the stator bar.
Abstract:
A cooling arrangement for the rotor of an electric machine with longitudinal slots having disposed therein exciter winding sections which must be cooled to a low temperature, the arrangement having a feed and discharge line, in which a multiplicity of individual cooling canals running in the circumferential direction and a multiplicity of individual radial coolant feed lines and/or discharge lines are provided for each winding section over its axial length so that the cooling arrangement can be optimized with regard to the thermodynamic pressure losses of the coolant, its temperature rise and the heat transfer conditions while at the same time achieving a favorable space factor of the conductor material within the slots.
Abstract:
A device for coupling two shafts of a rotating machine for permitting simultaneously a thermal dilatation and a sealing of the shafts with respect to each other, in combination with the shafts, includes inner and outer normally synchronously rotating mutually concentric shafts defining a ring gap therebetween, at least the outer shaft being hollow defining a space between the shafts, an expansion compensator with a given maximal permissible twist disposed between the inner periphery of the outer shaft with one end and the outer periphery of the inner shaft with its other end sealing the space between the shafts and permitting relative axial, radial and tangential motion between the shafts, a holding ring rotatably and sealingly supported on the inner shaft connected sealingly to said other end of the expansion compensator thereby permitting a twisting movement thereof with respect to the inner shaft, and at least one driver element attached to the outer shaft engaging the inner shaft via the holding ring with tangential play (S.sub.2) between the shafts being smaller than the given maximal permissible twist, the driver element mechanically connecting the holding ring, and the other end of said expansion compensator to the outer shaft when twists of the expansion compensator exceed the tangential play (S.sub.2).
Abstract:
A coolant replenishing system for cooling the superconducting field winding of a machine, illustratively a turbo-generator. The machine is provided with a rotating antechamber in which is disposed a coolant in liquid and gaseous phases. Liquid coolant is delivered to the antechamber from a supply tank by a coolant supply line. The discharge opening of the coolant supply line in the antechamber is oriented away from the axis of rotation of the machine, and disposed at a predetermined radius with respect to the axis so that the input pressure of the coolant at the opening of the coolant feed line is in equilibrium with the pressure of the liquid coolant in the rotating antechamber.
Abstract:
An improved rotor for an electric machine, particularly for a synchronous machine, comprising a field winding cooled to a low temperature in which the rotor includes a concentric, hollow, cylindrical support body having internal slots on its inside for accommodating the field winding so that the winding can be placed in the slots in a simple manner and the windings retained more securely therein.
Abstract:
A cryosorption pump for perpetuating a thermal insulating vacuum in the superconducting rotor of an electric machine, in particular, a turbogenerator, is constructed in a co-rotating transfer part of the rotor along the axis of rotation thereof. The rotor comprises a superconducting exciter winding part which is to be cooled by a cryogenic coolant, and to which winding part the coolant is introduced via at least one appropriate coolant supply line. The chambers of the rotor winding part to be evacuated are directly connected to the cryosorption pump in the co-rotating transfer part. Furthermore, the cryosorption pump is thermally connected within the co-rotating transfer part with the at least one coolant supply line.
Abstract:
An arrangement for cooling the field winding of an electric machine to be deep cooled is provided with a rotating mixing chamber containing vaporous and liquid coolant and with a centrifugal pump between areas of different temperatures to pump gaseous coolant out of the mixing chamber. The maximum flow cross section of the colder line part of the centrifugal pump is at the most half the size of the maximum flow cross section of the warmer line parts and/or at least the end piece of the colder line part is thermally coupled to colder parts of the rotor to prevent pump instabilities caused by coolant convection.
Abstract:
Cooling system for a rotor of an electric machine having a superconductive field winding and formed of a rotor drum with at least one outer, substantially hollow cylindrical rotor body with a co-rotating cold shield, an inner hollow rotor body fastened at given locations within the outer rotor body so as to be thermally insulated and serving as a coil-winding support, the fastening locations at the outer rotor body being cooled, and a co-rotating mixing chamber located at the inner periphery of the inner hollow rotor body and containing a phase mixture of a coolant fed thereto from the outside, the phase mixture forming, during rotation of the rotor, a radially outwardly flung liquidring and a radially inner vapor column coaxial thereto, including channels for conducting a first coolant flow with liquid coolant from the mixing chamber for cooling the field winding and a second coolant flow with at least partly vaporized coolant for cooling the fastening locations and for returning the first coolant flow, after it has traversed the field winding, back to the mixing chamber and for discharging the second coolant flow out of the electric machine.
Abstract:
In order to monitor the temperature of an electric generator, the temperatures of a plurality of rods of a stator winding of the generator being cooled by a coolant, preferably a water-cooled stator winding, are detected. In order to detect a temperature deviation in each winding rod, a measured actual or real temperature value of each winding rod is compared with a reference value for the winding rod. The reference value is derived from parameters previously determined for the winding rod by reference measurement and from presently or currently detected, operation-relevant parameters of the generator. The parameters for each winding rod are derived from a temperature of the winding rod detected during the reference measurement and from a number of functions that corresponds to the number of parameters. The functions are derived from operation-relevant parameters detected during the reference measurement in different states of operation of the generator. The temperature may thus be monitored while operation-relevant influencing variables, such as the stator current of the generator, are taken into account.