Abb Schweiz Ag

Abb Oy

Abb Technology Oy

Lappeenrannan-lahden Teknillinen Yliopisto Lut

Markku Niemelä

Jero Ahola

Jussi Tamminen

Tero Ahonen

Timo Holopainen

Olli Liukkonen

Jari Jäppinen

Ville Särkimäki

Vesa Ruuskanen

Tuomo Lindh

Joonas Koponen

Antti Kosonen

Anton Poluektov

A field of electric drive devices, drivetrain systems and electric machines, such as electric motors and electric generators for industrial applications, and more particularly to a method, an arrangement, and a frequency converter for identification of torsional natural frequencies of a drivetrain system. In the arrangement for identification of torsional natural frequencies of a drivetrain system according to the present invention, the drivetrain system includes a frequency converter, an electric machine controlled by the frequency converter, and a driven/driving machine system connected to the electric machine, wherein the frequency converter is arranged for controlling the electric machine for producing mechanical excitation by the electric machine in the drivetrain system, the excitation effecting an excitation response in the drivetrain system; and wherein the frequency converter or a data analysis system of the arrangement is arranged for identifying torsional natural frequencies of the drivetrain system utilizing the excitation response.

Method, an arrangement and a frequency converter for identification of torsional natural frequencies of a drivetrain system

A system for alkaline water electrolysis includes electrolysis cells, a hydrogen separator tank, a first piping from the electrolysis cells to the hydrogen separator tank, an oxygen separator tank, a second piping from the electrolysis cells to the oxygen separator tank, and a third piping for conducting liquid electrolyte from the hydrogen separator tank and from the oxygen separator tank back to the electrolysis cells. The system includes an ultrasound source for applying ultrasound on the liquid electrolyte contained by the first piping. The ultrasound enhances the separation of dissolved hydrogen gas from the liquid electrolyte contained by the first piping, and thus energy efficiency of the alkaline water electrolysis is improved. Furthermore, a safe control range of the alkaline water electrolysis is broadened because crossover of hydrogen gas to an oxygen side of the system is reduced.

System and a method for alkaline water electrolysis

An arrangement for monitoring an antifriction bearing of a rotating shaft of a rotating electric machine. The arrangement includes: one or more capacitor electrodes to measure a capacitive shaft displacement parameter; one or more of the following additional measurement sensors; a microphone to measure a bearing noise parameter, a voltage sensor to measure a bearing current parameter, and/or an optical pyrometer to measure a shaft heat parameter; and one or more processors configured to evaluate a condition of the antifriction bearing based on the capacitive shaft displacement parameter and one or more of the following: the bearing noise parameter, the bearing current parameter, and/or the shaft heat parameter.

Arrangement for monitoring antifriction bearing of rotating shaft of rotating electric machine

A method is provided for detecting the correct rotational direction of a centrifugal apparatus. The method includes rotating the centrifugal apparatus in a first direction, acquiring first frequency data relating to the step of rotating the centrifugal apparatus in the first direction, rotating the centrifugal apparatus in a second direction, which is opposite to the first direction, and acquiring second frequency data relating to the step of rotating the centrifugal apparatus in the second direction. The method also includes detecting the correct rotational direction of the centrifugal apparatus based on comparing the first frequency data with the second frequency data, the comparison being carried out with respect to at least one significant frequency range. In each of the at least one significant frequency range, a smaller magnitude is interpreted as an indication of the correct rotational direction.

Method for detecting the correct rotational direction of a centrifugal apparatus, and a centrifugal apparatus assembly

A method for determining a change in a mass of a fan impeller. The method includes inducing a torque to the fan impeller and determining a change in the angular speed of the fan impeller, induced by the torque. A value for a first parameter representing a present mass of the fan impeller is determined on the basis of the change in the angular speed and the torque. The change in the mass is then determined on the basis of the first parameter and a second parameter representing the reference mass of the fan impeller.

Method and apparatus for determining change in mass of fan impeller

Growing community of inventors

Lappeenranta, Finland

Markku Niemelä