Abstract: A vector control method for electric motors, characterized in that it comprises the steps of: supplying a reference vector (VoutMAX); supplying a required vector (Vf), preferably represented by means of a real vector component (Vq) and an imaginary vector component (Vd); comparing the magnitude (VMAX) of said reference vector (VoutMAX) with the magnitude of said required vector (Vf), generating at least one result (V6, index_clip) that expresses the relationship existing between said magnitudes; generating a reduction value (J) as a function of the result (V6, index_clip); and generating a clipped value (VfCLIP) by limiting the magnitude of the required vector (Vf) as a function of the reduction value (J) and maintaining the phase of the clipped value (VfCLIP) unaltered with respect to the phase of the required vector.

Abstract: A device for driving an electric motor includes: an inverter circuit, configured for converting a d.c. supply signal into an a.c. supply signal; and a control block, connected to the inverter circuit and configured for controlling the inverter circuit by means of a pulse-width modulation, having a given cycle-period value. The driving device further includes a first random-number generator, connected to the control block and configured for supplying to the control block pseudo-random or random cycle-period values.

Abstract: A control method for cooling a turbine stage of a gas turbine, whereby cooling air is bled from combustion air flowing in a compressor of the gas turbine, and is fed to a cooling circuit staring from a stator of the turbine stage; and cooling airflow is adjusted as a function of the pressure at the inlet of the cooling circuit, and as a function of the combustion air pressure at the exhaust of the compressor; more specifically, there is a feedback control setting a setpoint, which is predetermined as a function of the power output of the turbine to reduce contaminating emissions.

Abstract: A gas turbine equipped with a burner, which has an axial swirler for generating turbulence in a flow of comburent air, a secondary supply line of fuel gas, a main supply line of fuel gas arranged concentrically around the secondary line, and a pilot line of fuel gas. Accordingly, the burner is ignited by firing a spark and feeding, towards the spark, comburent air and fuel gas which is synthesis gas.

Abstract: An oil cleaning device is provided with: at least a first electrostatic cleaner comprising at least one voltage source, and at least two metal plates connected to said voltage source; and at least one free radical sensor for determining the content and/or type of free radicals in the oil.

Abstract: A gas turbine compressor presents a first fixed stage having a plurality of first adjustable vanes and a further fixed stage, which has an inner ring extending about a first axis; an outer ring arranged about the inner ring and coaxial with the inner ring; and a plurality of second adjustable vanes, each of which extends along a second axis in an essentially radial direction with respect to the first axis between the inner ring and the outer ring; and it is adjustable about the corresponding second axis independently from the first adjustable vanes.

Abstract: A stator of a turbo generator for the generation of electrical energy is provided with: a cylindrical core, which extends along a longitudinal axis and presents a plurality of axial cavities and two opposite headers; connection terminals of the turbo generator; a plurality of electrical windings, which are split into groups and which extend along paths defined in part in the axial cavities and in part at the headers; the electrical windings of each group being isopotential and connected in parallel between a pair of terminals; and a plurality of connection devices, each of which is adapted to define, at least at one of the headers, a segment of path in common with the isopotential electrical windings.

Abstract: A method of analysis of secondary-air circuits in gas-turbine plants includes defining an equivalent fluid-dynamic network of a secondary-air circuit of a gas-turbine plant. The equivalent fluid-dynamic network includes a plurality of elements, organized in branches and connected to nodes. For at least one element of the secondary-air circuit a principal component of flow and at least one auxiliary component of flow are calculated.

Abstract: A ventilated rotor of a high-power turbogenerator for the production of electricity has a shaft extending along an axis; a plurality of axial slots obtained in the shaft; a plurality of conductor bars arranged at least partly in the slots; a plurality of axial channels suitable for ventilating the conductor bars; a plurality of subslots, each of which is arranged below a slot to distribute a ventilating gas; a plurality of axial portions traveled over by respective flows of ventilating gas along each axial channel; and at least one radial channel, which is intended to convey directly the ventilating gas from the subslot to the outer surface of the rotor via the conductor bars and is arranged between two consecutive and adjacent axial portions of an axial channel.

Abstract: An apparatus for experimental investigation of axial seal systems of gas turbines includes a test structure having a test chamber, which is delimited by a first seal portion and by a second seal portion and extends along an axis. At least one of the first seal portion and the second seal portion is provided with a series of ribs transverse to the axis The first seal portion and the second seal portion are arranged facing each other so as to form an axial seal system according to the axis. Furthermore, the first seal portion and the second seal portion are at least partially made of a transparent material.

Abstract: A control device of a gas turbine electric energy production plant, which delivers a power at a frequency presents power control means for controlling the power delivered by the plant according to a reference power value, and frequency control means, for determining correction values of the reference power value according to a frequency error, given by the difference between the plant frequency and a nominal frequency, which comprise integral control means configured to calculate the correction values and selectively activatable when the frequency error is beyond a first frequency range.

Abstract: A control device of a gas turbine electric energy production plant, which delivers a power at a frequency presents power control means, for controlling the power delivered by the plant by means of a first control signal which determines the supply of fuel to a portion of the plant according to a reference power value, and frequency control means, for determining correction values of the reference power value according to a frequency error, given by the difference between the plant frequency and a nominal frequency which comprise step control means configured to adjust the supply of fuel to the portion of the plant by means of a second control signal concurrent with the first control signal, when the derivative of the frequency of the plant assumes values higher than a threshold value.

Abstract: A stage of a steam turbine, having a rotor extending along a longitudinal axis, has a fixed stage and a movable stage arranged successively along a flow channel for feeding steam in a direction substantially parallel to the longitudinal axis; the fixed stage has an inner ring coaxial with the longitudinal axis, and a number of stator blades arranged radially about the inner ring; each stator blade is fixed to an annular top portion of the inner ring, which has a top surface facing the flow channel and crosswise to the longitudinal axis; and the movable stage has a number of rotor blades arranged radially about the rotor and fixed to the rotor.

Abstract: A gas turbine blade has: a main hollow body substantially extending along a longitudinal axis and having a leading edge, a trailing edge, opposite to the leading edge, a suction side, and a pressure side, both comprised between the leading edge and the trailing edge; a hollow cooling element extending along the axis, which is equipped with a plurality of cooling holes and is set within the main body so as to define a gap between the main body and the cooling element; and a rib, which is set within the gap for connecting the main body with the cooling element on the suction side, in an area of the main body without holes for communication between the gap and the outside of the blade.

Abstract: A maintenance method of a gas turbine unit, having a first stator element provided with first connecting holes contemplates replacing a second stator element, provided with second connecting holes and connected to the first stator element by means of coupling pins insertable into the first and the second connecting holes, with a third spare stator element provided with third connecting holes; and coupling the first stator element to the third spare stator element by means of eccentric coupling pins and eccentric bushes, each of which is selectively insertable in the first and the third connecting holes.

Abstract: A graphic tool and a method are provided, to represent corporate data in terms of know-how and intellectual property management risk and in terms of corporate functional breakdown by asset. The tool and method may be used to evaluate risk associated with events related to know-how and intellectual property management and capable of affecting or interrupt production. The tool and method also allow analysis of company production structure, for the purpose of functional or corporate reorganization.

Abstract: A turbine burner (1) comprising a secondary feed unit for the supply of a backup mixture and a primary feed unit intended for the supply of a primary mixture comprising lean gas, comprising a primary mixture channel (24). The primary mixture channel (24) has an annular wall (28) having a truncated cone-shaped end portion (30) capable of conveying the primary mixture directly to the combustion zone (6) facing the axial swirler (18), achieving efficient combustion even for primary mixtures comprising gases with a low calorific value.

Abstract: A system for damping thermo-acoustic instability in a combustor device for a gas turbine, the combustor device including at least one combustion chamber, in particular of an annular type, and at least one burner associated to the combustion chamber and mounted in a position corresponding to a front portion set upstream of the combustion chamber; the damping system including at least one Helmholtz resonator including a casing defining inside it a pre-set volume and a neck for hydraulic connection between the pre-set volume and the combustion chamber, the neck being connected to one side of the combustion chamber at a distance from the front upstream portion thereof provided with the at least one burner. The casing of the resonator includes structure which varies the pre-set volume within a pre-set range and structure which delivers a cooling fluid.

Abstract: A sealing element for a gas turbine, which is provided with at least one rotor ring and at least a plurality of rotor blades radially arranged about the rotor ring and having an end portion fixed to the rotor ring, is provided with a wall, which is adapted to be coupled to the rotor ring and to at least one rotor blade, has an external face adapted to be arranged in contact with a hot working fluid in the gas turbine and an internal face adapted to be arranged in contact with a cooling fluid of the gas turbine, and a gap, which is adapted to be travelled through by the cooling fluid.

Abstract: A method of analysis of secondary-air circuits in gas-turbine plants includes defining an equivalent fluid-dynamic network of a secondary-air circuit of a gas-turbine plant. The equivalent fluid-dynamic network includes a plurality of elements, organized in branches and connected to nodes. For at least one element of the secondary-air circuit a principal component of flow and at least one auxiliary component of flow are calculated.