Abstract: An inductive device comprises a toroidal core and at least one electric conductor wound around the toroidal core and constituting at least one winding. The inductive device comprises a cooling element constituting a cylindrical cavity that contains the toroidal core and the electric conductor so that the axial direction of the toroidal core is parallel with the axial direction of the cylindrical cavity. The shape of the cylindrical cavity and the cross-section of the electric conductor are adapted to match each other to improve heat transfer from the electric conductor to the wall of the cylindrical cavity so that a wall of the cylindrical cavity is provided with axially directed grooves occupied by portions of the electric conductor on an outer perimeter of the winding.

Abstract: A positioning device (101) for producing a position signal indicative of a rotational position of a resolver is disclosed. The positioning device includes a signal interface (102) for receiving alternating signals (V_cos, V_sin) from the resolver and a processing system (103) for generating the position signal based on position-dependent amplitudes of the alternating signals and on polarity information indicative of a polarity of an excitation signal (V_exc) of the resolver. The processing system is configured to recognize a polarity indicator, such as a change of frequency or phase, on a waveform of one or both of the alternating signals and to determine the polarity information based on the recognized polarity indicator. Thus, the polarity information related to the excitation signal is included in the alternating signals and therefore there is no need for a separate signaling channel for transferring the polarity information to the positioning device.

Abstract: A positioning device (101) for producing a position signal indicative of a rotational position of a resolver is presented. The positioning device comprises a signal interface (102) for receiving alternating signals (V_cos, V_sin) from the resolver and a processing system (103) for generating the position signal based on position-dependent amplitudes of the alternating signals and on polarity information indicative of a polarity of an excitation signal (V_exc) of the resolver. The processing system is configured to recognize a polarity indicator, such as a change of frequency or phase, on a waveform of one or both of the alternating signals and to determine the polarity information based on the recognized polarity indicator. Thus, the polarity information related to the excitation signal is included in the alternating signals and therefore there is no need for a separate signaling channel for transferring the polarity information to the positioning device.

Abstract: A device-system comprises parallel operating devices (105-107) for driving an operating quantity towards a target value, and a control system for controlling each device at least partly based on a device-specific integral term relating to a time integral of a device-specific error signal that is indicative of a deviation of the operating quantity from the target value. The control system comprises a stabilizing system that computes an arithmetic average of the device-specific integral terms and corrects the device-specific integral terms towards the computed arithmetic average. The correction of the device-specific integral terms makes it possible to avoid unwanted drifts in the device-specific integral terms in a situation where there are differences between the device-specific error signals. The devices can be peers to each other and thus redundancy is achieved because one device can be removed from or added to the device-system without actions from the other devices.

Abstract: An electric power system comprises recording devices (101-105) located at different elements of the electric power system and configured to record waveform samples of quantities related to operation of the elements of the electric power system. The electric power system comprises a central device (106) configured to receive the recorded waveform samples from the recording devices. The recording devices are synchronized to maintain a common clock time and to associate, to each of the recorded waveform samples, one or more timing values indicative of the clock time during recording the waveform sample. As the timing values are associated to the waveform samples, it is possible to reconstruct a time order of phenomena indicated by the recorded waveform samples. Thus, it is possible to identify which of the phenomena are causes and which are consequences when analyzing for example what happened prior to a fault situation.

Abstract: A device-system comprises parallel operating devices (105-107) for driving an operating quantity towards a target value, and a control system for controlling each device at least partly based on a device-specific integral term relating to a time integral of a device-specific error signal that is indicative of a deviation of the operating quantity from the target value. The control system comprises a stabilizing system that computes an arithmetic average of the device-specific integral terms and corrects the device-specific integral terms towards the computed arithmetic average. The correction of the device-specific integral terms makes it possible to avoid unwanted drifts in the device-specific integral terms in a situation where there are differences between the device-specific error signals. The devices can be peers to each other and thus redundancy is achieved because one device can be removed from or added to the device-system without actions from the other devices.

Abstract: A positioning device (101) for producing a position signal indicative of a rotational position of a resolver is presented. The positioning device comprises a signal interface (102) for receiving alternating signals (V_cos, V_sin) from the resolver and a processing system (103) for generating the position signal based on position-dependent amplitudes of the alternating signals and on polarity information indicative of a polarity of an excitation signal (V_exc) of the resolver. The processing system is configured to recognize a polarity indicator, such as a change of frequency or phase, on a waveform of one or both of the alternating signals and to determine the polarity information based on the recognized polarity indicator. Thus, the polarity information related to the excitation signal is included in the alternating signals and therefore there is no need for a separate signaling channel for transferring the polarity information to the positioning device.

Abstract: An electric power system comprises recording devices (101-105) located at different elements of the electric power system and configured to record waveform samples of quantities related to operation of the elements of the electric power system. The electric power system comprises a central device (106) configured to receive the recorded waveform samples from the recording devices. The recording devices are synchronized to maintain a common clock time and to associate, to each of the recorded waveform samples, one or more timing values indicative of the clock time during recording the waveform sample. As the timing values are associated to the waveform samples, it is possible to reconstruct a time order of phenomena indicated by the recorded waveform samples. Thus, it is possible to identify which of the phenomena are causes and which are consequences when analyzing for example what happened prior to a fault situation.

Abstract: A device (101) for producing a position signal indicative of rotational position of a resolver is presented. The device comprises a signal transfer interface (102) for receiving first and second alternative signals, and a processing system (103) for generating the position signal on the basis of the amplitudes of the first and second alternative signals and the polarity of an excitation signal of the resolver. The device is configurable to operate in a first operational mode where a local signal generator (104) generates the excitation signal and the device transmits the excitation signal to the resolver. The device is configurable to operate also in a second operational mode where the device receives information indicative of the polarity of the excitation signal from another device. Thus, devices of the kind described above can be used in a system where many converters are driving separate windings systems of an electrical machine.

Abstract: An inductive device includes a toroidal core and at least one electric conductor wound around the toroidal core and constituting at least one winding. The inductive device includes a cooling element constituting a cylindrical cavity that contains the toroidal core and the electric conductor so that the axial direction of the toroidal core is parallel with the axial direction of the cylindrical cavity. The shape of the cylindrical cavity and the cross-section of the electric conductor are adapted to match each other so as to improve heat transfer from the electric conductor to the wall of the cylindrical cavity. The cylindrical cavity can have for example a circular base and the electric conductor can have for example a rectangular cross-section that matches the shape of the wall of the cylindrical cavity better than a round electric conductor.

Abstract: A capacitor module includes at least one capacitor element (101) and a cooling structure (103) for cooling the capacitor element. The electrical terminals (102a, 102b) of the capacitor element are mechanically connected to the cooling structure to be in heat-conductive relations with the cooling structure so that at least one of the electrical terminals of the capacitor element is mechanically connected to the cooling structure via a flexible connection element (104a, 104b) made of electrically conductive material. The flexible connection element allows the corresponding electrical terminal to move with respect to the cooling structure when the distance (D) between the electrical terminals is changing because of changes in load and/or temperature, and/or because of ageing.

Abstract: A device (101) for producing a position signal indicative of rotational position of a resolver is presented. The device comprises a signal transfer interface (102) for receiving first and second alternative signals, and a processing system (103) for generating the position signal on the basis of the amplitudes of the first and second alternative signals and the polarity of an excitation signal of the resolver. The device is configurable to operate in a first operational mode where a local signal generator (104) generates the excitation signal and the device transmits the excitation signal to the resolver. The device is configurable to operate also in a second operational mode where the device receives information indicative of the polarity of the excitation signal from another device. Thus, devices of the kind described above can be used in a system where many converters are driving separate windings systems of an electrical machine.

Abstract: A capacitor module includes at least one capacitor element (101) and a cooling structure (103) for cooling the capacitor element. The electrical terminals (102a, 102b) of the capacitor element are mechanically connected to the cooling structure to be in heat-conductive relations with the cooling structure so that at least one of the electrical terminals of the capacitor element is mechanically connected to the cooling structure via a flexible connection element (104a, 104b) made of electrically conductive material. The flexible connection element allows the corresponding electrical terminal to move with respect to the cooling structure when the distance (D) between the electrical terminals is changing because of changes in load and/or temperature, and/or because of ageing.

Abstract: The invention relates to an electronic circuit and method for testing a line (10). According to the invention the signal generator (20, 30) comprises a random bit series generating means for generating a spread spectrum test signal and the evaluating unit comprises means (60-90, 200-230) for calculating and evaluating the correlation function of the test signal and the reflected signal.

Abstract: A measuring method and a measuring apparatus which transmits to a transmission line a measuring signal, a part of which is reflected back to the measuring apparatus which comprises a processor which measures the reflected signal. The processor transmits a measuring signal to the transmission line and the processor measures the magnitude of the measuring signal before the measuring signal is transmitted and the processor compares the measuring result with the magnitude of the reflected measuring signal. In addition, the processor calculates a reflection coefficient for the transmission line in the frequency domain by means of the measuring results. Further, the processor calculates an impulse response for the transmission line by means of the refection coefficient in the frequency domain.

Abstract: The invention relates to a measuring method and a measuring apparatus which transmits to the transmission line a measuring signal, a part of which is reflected back to the measuring apparatus which comprises a processing means which measures the reflected signal. The processing means transmits a measuring signal to the transmission line and the processing means measures the magnitude of the measuring signal before the measuring signal is transmitted and the processing means compares the measuring result with the magnitude of the reflected measuring signal. In addition, the processing means calculates a reflection coefficient for the transmission line in the frequency domain by means of the measuring results. Further, the processing means calculates an impulse response for the transmission line by means of the refection coefficient in the frequency domain.